Ionic Liquids: Synthesis and Applications in Catalysis

Review ArticleIonic Liquids Synthesis and Applications in Catalysis

Rajni Ratti12

1 Maitreyi College New Delhi 110021 India2Miranda House University of Delhi New Delhi 110007 India

Correspondence should be addressed to Rajni Ratti rajnirattigmailcom

Received 2 June 2014 Revised 20 August 2014 Accepted 1 September 2014 Published 29 October 2014

Academic Editor Hideaki Shirota

Copyright copy 2014 Rajni Ratti This is an open access article distributed under the Creative Commons Attribution License whichpermits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Ionic liquids have emerged as an environmentally friendly alternative to the volatile organic solvents Being designer solvents theycan be modulated to suit the reaction conditions therefore earning the name ldquotask specific ionic liquidsrdquo Though primarily usedas solvents they are now finding applications in various fields like catalysis electrochemistry spectroscopy and material science tomention a fewThepresent review is aimed at exploring the applications of ionic liquids in catalysis as acid base and organocatalystsand as soluble supports for catalysts

1 Introduction

One of the twelve principles of green chemistry is that theuse of auxiliary substances such as solvents and separationagents should be made unnecessary and if used shouldbe innocuous [1] The toxic and hazardous properties ofmany solvents particularly chlorinated hydrocarbons posecrucial environmental concerns such as atmospheric emis-sions and contamination of water effluents It is recognizedthat employing the use of nonconventional solvents as alter-natives for environmentally unfriendly traditional solventscan reduce waste solvent production and hence reduce thenegative impact on environment to a great extent [2] Themost prevalent of these new solvent systems includes but notexclusively water supercritical fluids (like supercritical CO

2)

ionic liquids solventless processes and fluorous techniques[3]

Of all the above mentioned nonconventional solvents ofinterest ionic liquids have emerged as a promising alternative[4] Ionic liquid is defined as a salt with melting pointbelow the boiling point of water [5] Ionic liquids are knownby several different names like neoteric solvents designersolvents ionic fluids and molten salts Most of the ionicliquids are composed of organic cation and inorganic anionsIn order to be liquid at room temperature the cation shouldpreferably be unsymmetrical that is the alkyl groups shouldbe different Polarity and hydrophilicityhydrophobicity of

ionic liquids can be tuned by suitable combination of cationand anion It is this property of ionic liquids which has earnedthem the accolade ldquodesigner solventsrdquo

As solvents ionic liquids have found applications ina number of reactions [6ndash16] Dupont et al extensivelyreviewed the application of ionic liquids as catalytic phase invarious organometallic reactions [17] Catalytic applicationsof metal nanoparticles have been explored in ionic liquidmedia by Migowski and Dupont [18 19]

Besides the use of ionic liquids as alternate solventslately further work has led to the progress in designing func-tional ionic liquids also referred to as ldquotask specific ionic liq-uidsrdquo (TSIL) [20]The term task specific ionic liquids or func-tionalized ionic liquids actually indicates an attempt to capi-talize on the potential ldquodesignrdquo capacity of ionic liquids andmake them true working systems rather than just reactionmedia

2 Synthesis of Ionic Liquids

The first room temperature ionic liquid [EtNH3][NO3] (mp

12∘C) was discovered in 1914 [21] but interest did notdevelop until the discovery of binary ionic liquids made frommixtures of aluminum(III) chloride and N-alkylpyridiniumor 13-dialkylimidazolium chloride [22 23]

Hindawi Publishing CorporationAdvances in ChemistryVolume 2014 Article ID 729842 16 pageshttpdxdoiorg1011552014729842

2 Advances in Chemistry

(1) +Metal salt M+[A]minus

minusMX (precipitation)(2) +Bronsted acid H+

[A]minus

minusHX (evaporation)(3) Ion exchange resin

Step I

Step IIa Step IIb+Lewis acid

MXy

+R998400X

NR3

[R998400R3N]+[MXyminus1]minus

[R998400R3N]+[A]minus

[R998400R3N]+Xminus

Figure 1 Synthesis path for the preparation of ionic liquids [24]

[emim]+Clminus + AlCl3 [emim]

+[AlCl4]

minus

[emim]+[AlCl4]

minus+ AlCl3 [emim]

+[Al2Cl7]

minus

[emim]+[Al2Cl7]

minus+ AlCl3 [emim]

+[Al3Cl10]

minus

(1)

(2)

(3)

Scheme 1 Series of equilibria in the reaction between [emim]Cl andAlCl3

Ionic liquids come in twomain categories namely simplesalts (made of a single anion and cation) and binary ionicliquids (salts where equilibrium is involved) For example[EtNH

3][NO3] is a simple salt whereas mixtures of alu-

minum(III) chloride and 13-dialkylimidazolium chlorides (abinary ionic liquid system) contain several different ionicspecies and their melting point and properties dependupon the mole fractions of aluminum(III) chloride and 13-dialkylimidazolium chloride present

The synthesis of ionic liquids can be described in twosteps (Figure 1)

(1) The Formation of the Desired Cation The desired cationcan be synthesized either by the protonation of the amine byan acid or through quaternization reactions of amine with ahaloalkane and heating the mixture

(2) Anion ExchangeAnion exchange reactions can be carriedout by treatment of halide salts with Lewis acids to formLewisacid-based ionic liquids or by anion metathesis

The most extensively studied and used Lewis acid basedionic liquids are AlCl

3based salts [25ndash27] Such salts involve

simple mixing of the Lewis acid and the halide salt whichresults in the formation of more than one anionic speciesdepending upon the ratio of quaternary halide salt Q+Xminusand Lewis acid MX

119899as illustrated by the reaction between

[emim]Cl and AlCl3in Scheme 1

When [emim]Cl is present in molar excess over AlCl3the

ionic liquid formed is basic (1) however the molar excessof AlCl

3leads to the formation of an acidic ionic liquid (3)

When both [emim]Cl and AlCl3are present in equimolar

quantities it results in the formation of neutral ionic liquidsApart from AlCl

3 other Lewis acids used are AlEtCl

2[28]

BCl3[29] CuCl [30] and InCl

3[31] to mention a few

Anion metathesis is the methodology of choice for thepreparation of water and air stable ionic liquids based upon

Table 1 Examples of ionic liquids prepared by anion metathesis

Salt Anion source References[Cation][PF6] HPF6 [32ndash34][Cation][BF4] HBF4 NH4BF4 NaBF4 [33ndash37][Cation][(CF3SO2)2N] Li[(CF3SO2)2N] [34 38][Cation][CF3SO3] CF3SO3CH3 NH4[CF3SO3] [38][Cation][CH3CO2] Ag[CH3CO2] [35][Cation][CF3CO2] Ag[CF3CO2] [35][Cation][CF3(CF3)3CO2] K[CF3(CF3)3CO2] [38][Cation][NO3] AgNO3 NaNO3 [34 38][Cation][N(CN)2] Ag[N(CN)2] [39][Cation][CB11H12] Ag[CB11H12] [40][Cation][AuCl4] HAuCl4 [41]

13-dialkylimidazolium cations This method involves thetreatment of the halide salt with the silversodiumpotassiumsalts of NO

2

minus NO3

minus BF4

minus SO4

2minus and CO2CH3

minus or with thefree acid of the appropriate anion Table 1 gives examples ofthe few ionic liquids prepared by anion metathesis

It is clear from the above discussion that large numberof ionic liquids can be envisioned by simple combination ofdifferent cations and anions The estimated number of singleILs is 1018 which further increases if we include binary andternary ionic liquids Because of their ldquotailor-maderdquo naturethe ionic liquids find applications as storage media for toxicgases catalystssolvents in organic syntheses performanceadditives in pigments and matrices [42ndash44]

Several new and improved methodologies using noncon-ventional techniques such as irradiation with microwaves(MW) and power ultrasound (US) whether used alone orin combination have considerably improved the synthesisof ILs cutting down reaction times and improving yields[45ndash47]The recent introduction of efficient solventless one-pot synthetic protocols should make ILs cheaper and thusencourage a wider use of these neoteric solvents [48ndash50]

3 Task Specific Ionic Liquids (TSILs)

In 1999 Davis Jr and Forrester demonstrated the concept ofdesigning ionic liquid to interact with a solute in a specificmanner by using a thiazolium based IL as a solvent-catalystfor the benzoin condensation and introduced the term ldquotaskspecific ionic liquidrdquo for such ILs in which functional group

Advances in Chemistry 3

N NRFG

CatalysisOrganic synthesisExtraction and dissolutionSAMs or nanoparticlesConductive materialsetc

+

-NH2

-OH OR-SH-PPh2-Si(OR)3-Urea and thiourea-Metal complex-Etc

IL FG IL FG

TSIL

+

Figure 2

IonTSIL

exchange

= Nucleophile

+ +X-(CH2)x FG FG(CH2)x Xminus

Figure 3

HX H

R

OR

O+ ++

= Imidazole phosphine etc

XminusXminus

Figure 4

is incorporated as a part of the cation andor anion structure[51 52] The covalent attachment of some functional groupto cationanion or both of an ordinary ionic liquid imparts itthe capacity to behave not only as solvent but also as reagentandor catalyst catalyst in the chemical reactions [53 54] (seeFigures 2 and 3)

(i) For example safe to handle Bronsted acidic ionic liq-uids containing sulphonic acid groups were used assolvent andor catalyst for esterification and otheracid catalyzed reactions [55]

(ii) Ionic liquids bearing appended amines can separatecarbon dioxide from gas streams [56]

(iii) Ionic liquids with large aromatic head groups showenhanced activity for extraction of aromatics in aque-ous biphasic systems [57]

(iv) Ionic liquids with a tethered hydroxyl group (minusOH)have been used as phase transfer catalyst in the syn-thesis of ethoxybenzene [58]

(v) Ionic liquids containing metal ligating group find usein the extraction of metal ions from aqueous solution[59]

(vi) Ionic liquids with appended carboxylate groups havebeen used as supports for ldquoIL-phaserdquo synthesis whichis a versatile extension of the solid phase synthesisconcept [60]

A TSIL can be any of the following two types [61](i) A room temperature ionic liquid having covalently

attached functional group behaves not just as reac-tion media but also as reagentcatalyst

(ii) A binary system of some functionalized salt whichmay be solid at room temperature dissolved in con-ventional ionic liquid

31 Synthesis of TSILs Conventional method used for syn-thesizing a TSIL involves the displacement of halide froman organic by a parent imidazole phosphine and so forthwhereby the organic halide already incorporates a desiredfunctional group The displacement reaction is followed byanion exchange (see Figure 3)

Thismethod is suitable for the synthesis of all ionic liquidswhich are stable towards bases however because of the strongbasicity of imidazole elimination of hydrogen halide or Hoff-mann elimination occurs in some cases [62] Generally thefunctional groups have been introduced directly to theimidazolium moiety using the direct quaternization routeFor example imidazolium cation with hydroxyl groups [58]carboxyl groups [60] thiol groups [63] alkyne groups [64]allyl groups [65] and fluorous chains [66] were successfullyprepared

Wasserscheid and coworkers introduced a new method-ology to synthesize TSILs by making use of Michael reaction


NR NH

O

NR N

OH+

+

Xminus Xminus

Scheme 2

COOH

H

H

NNHO

H R

NEtBr NHO

H RNH2

NH3 CH2O (CHO)2+ + +

+lowast lowast

Brminus

Scheme 3

NH

O

+

+RCOOH R998400OH RCOOR998400

CH3SO3minus

Scheme 4

NHR

EWG

N N

NH

EWG

+

+

R1

SO3H

R1

Tsminus

Scheme 5

In this approach the nucleophile is protonated using the acidform of anion which will eventually be incorporated into theionic liquid [67] (see Figure 4)

To synthesize minusOH group containing TSILs two proce-dures have been reported as discussed below

Holbrey et al have described a simple high yieldingone pot method for the synthesis of alcohol-appended imi-dazolium TSIL an ionic liquid type which was previouslydifficult to prepare cleanly Preformed imidazolium-H salt ofTSIL anion is allowed to react with an epoxide leading to ringopening without further alcohol-epoxide oligomerization[68] (see Scheme 2)

Bao et al synthesized an imidazolium ring by the fourcomponents condensation of amino acids ammonia formal-dehyde and glyoxal The procedure yields an optically activeTSIL [69] (see Scheme 3)

4 Ionic Liquids as Catalysts

Although ionic liquids were initially introduced as alternativegreen reaction media because of their unique physical andchemical properties today they have marched far beyondthis border showing their significant role in controlling thereaction as catalysts [70ndash75] Depending upon the functional

group attached to the cation andor anion the ionic liquidmay behave as an acidic basic or organocatalyst

41 As Acid Catalysts The application of acidic (Bronstedas well as Lewis) task specific ionic liquids (TSILs) as a cat-alytic material is growing rapidly in the field of catalysis[76 77] Combining the useful characteristics of solid acidsand mineral acids TSILs have been synthesized to replacethe traditionalmineral liquid acids such as hydrochloric acidand sulphuric acid in the chemical reactions In view ofgreen chemistry the substitution of harmful liquid acids byreusable TSILs is one of the most promising catalytic systemsin chemistry

The acidic nature of Bronsted acidic ionic liquids as cata-lysts has been exploited formany organic transformations likePechmann reaction Koch carbonylation asymmetric Aldolcondensation Aza-Michael reaction Beckmann rearrange-ment synthesis of chalcones oxidation reactions and Prinrsquosreaction synthesis of furfural biodiesel Hantzsch reactionand Mannich reaction to mention a few [78ndash89]

Esterification of alcohols by carboxylic acids has beencarried out in a halogen-free Bronsted acidic ionic liquid N-methyl-2-pyrrolidinium methyl sulphonate under mild con-ditions and without additional solvent [90] (see Scheme 4)


N N+

SO3H

[SBMI][HSO4]

N N+

SO3H

[SBMI][MeSO3]

N N+

SO3H

[SBMI][p-TsO]

N+

SO3H

[SBTA][p-TsO]

SO3H

[SBPP][p-TsO]

Ph

PhPh

P +

[SBP][p-TsO]

N+

SO3H

HSO4minus MeSO3

minus p-TsOminus

p-TsOminusp-TsOminus

Figure 5

PCl3 Ph-H[trEHAm]Cl-XAlCl3] PhPCl2+

Scheme 6

In a very recent report of TSIL Das and coworkershave reported a sulfonic acid functionalized IL for efficientsynthesis of indole derivatives [91]The advantage of this IL isthat it could be reused up to 10 cycles without any substantialloss of catalytic activity The catalyst is versatile as it is alsoapplicable to both aliphatic and aromatic amines and in thesynthesis of bis(indolyl) methane (see Scheme 5)

Z-W Wang and L-S Wang reported the Friedel-Craftsreaction of PCl

3and benzene in [trEHAm]Cl-XAlCl

3ionic

liquid for the clean synthesis of dichlorophenylphosphine(DCPP) [93] (see Scheme 6)

Comparedwith the classical methods this protocol allowsthe simple product isolation and lesser reusable catalyst con-sumption which contributes to the greenness of the proce-dure

Wang et al screened various ionic liquids for Saucy-Marbet reaction between unsaturated alcohols and unsatu-rated ethers leading to corresponding unsaturated ketones[94] It was observed that with five ionic liquids bearing[HSO

4

minus] anion the conversion decreases as the chain lengthof ionic liquid increases due to its lipophilic character Amongthe various acidic ionic liquids [Et

3NH] HSO

4gave the best

results in terms of conversion (88) and selectivity (97)for the model reaction involving dehydrolinalool and 2-ethoxypropene

With neutral ionic liquids like [bmim]BF4 the conver-

sion was less than 10 No reaction was observed when[bmim]Cl or [bmim]PF

6was used as catalystThis cost effect-

ive solvent-free protocol has the advantages of easy work-up recyclability with only slight decrease in activity lowtoxicity of ammonium based ionic liquids high activity andselectivity (see Scheme 7)

Brandt et al extensively reviewed the use of ionic liquidsas deconstruction solvents for lignocellulosic biomass [95]

Ionic liquid disrupts the lignin and hemicellulosic networkwhile decrystallizing the cellulose portion which furtherenhances the speed of saccharification

The use of ionic liquids [C4C1im][HSO

4] and

[C4C1im][MeSO

3] for lignocellulosic biomass treatment was

successfully investigated even in the presence of significantquantities of water thus eliminating the need for anhydrousconditions during pretreatment [96]

The use of acidic ionic liquids for the saccharificationof cellulose and its subsequent conversion into importantplatformmolecules like hydroxymethylfurfural furfural andlevulinic acid has been well explored [97ndash103]

A green solvent-free metal-free mild and efficient pro-tocol for the synthesis of 3-vinyl indoles starting from indolesand ketones has been developed using a sulfonyl containingionic liquid as a recyclable catalyst [104] The simultaneouspresence of sulfonyl and sulphonic acid groups in the sameionic liquid leads to an augmented catalytic activity Even thechallenging substrates like bulky ketones or ortho-substitutedketones gave satisfactory yields (see Scheme 8)

Six different Bronsted acidic ionic liquids (BAILs) havebeen synthesized and used as recyclable reaction media aswell as acid promoters for Pd-phosphine catalyzed methoxycarbonylation of ethylene to produce methyl propionate inexcellent yields [105] (see Figure 5)The use of BAILs not onlyhampered the formation of undesirable palladium black butalso leads to the formation of a biphasic reaction media withthe product thereby facilitating the product as well as catalystrecoveryThe catalytic system has been found to be recyclableup to fifteen cycleswithout any appreciable loss in activity (seeScheme 9)

Titze-Frech and coworkers developed an efficient andselective methodology for the alkylation of phenol andanisole using Bronsted acidic triflate ionic liquid [MIMBS][OTf] as catalyst in a biphasic reaction medium [106] Thisprotocol is advantageous over the existing ones as it negatesthe need for the neutralization of excess acid formed as aby-product Also ionic liquid catalyst being less oxophilic ascompared to mineral acids leads to greater selectivities (seeScheme 10)


R1

R2OR3

OH

ILs R3O OR3

R1 = CH3

R2 = H or (CH3)2CCH(CH2)2R3 = CH3 C2H5

+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13

Multi-alkylatedproducts

+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11

42 As Base Catalysts Basic functionalized ionic liquids havearoused unprecedented interest because they showed moreadvantages such as convenient recycling and higher catalyticefficiency than the mixture of inorganic base and ionic liquidfor some base-catalyzed processes [107]

Basic ionic liquids have been used to catalyze a numberof reactions like aza-Michael addition reactionMichael addi-tion of active methylene compounds condensation reactionof aldehydes and ketones with hydroxylamine synthesis ofquinolines pyrroles and AGET ATRP of methyl methacry-late to mention a few [108ndash113]

A facilemild and quantitative procedure for the prepara-tion of tetrahydrobenzo[b] pyran derivatives in the presenceof an easily accessible basic ionic liquid [bmim]OHas catalyst

has been developed by Wen et al [114] The ionic liquidwas used for at least nine times with consistent activity (seeScheme 11)

Xu et al developed a green protocol for the Michaeladdition of N-heterocycles to 120572120573-unsaturated compounds atroom temperature using a basic ionic liquid [bmim]OH as acatalyst and reaction medium [115] (see Scheme 12)

Wang and coworkers described synthesis and applicationof ethanolamine functionalized TSIL for the palladium-catalyzed Heck reaction [116] (see Scheme 13)

Here this IL performs a multifunctional role of base lig-and and reactionmediawith added advantage of recyclabilityof the system The catalyst system is very effective for a widespectrum of substrates giving excellent yields


NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH

No additional baseNo phosphineRecoverable TSILRecoverable catalyst

Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid

Cat BrTBDPEG150 TBDBr

+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14

Yang et al designed a series of PEG functionalizedbasic ionic liquids based on 12-dimethyl imidazole (DMIm)18-diazabicyclo [540] undec-7-ene (DBU) 15-diazabicyclo[430] non-5-ene (DBN) 1-methyl imidazole (MIm) and157-triazabicyclo [440] dec-5-ene (TBD) and tested themas catalysts under identical conditions for the conversion ofcarbon dioxide into useful organic carbonates [117] Of allthese catalysts BrTBDPEG

150TBDBr has been found to be

excellent recyclable catalyst under solvent-free conditions atlow pressure (see Scheme 14)

The presence of both secondary and tertiary nitrogens inthe cation of BrTBDPEG

150TBDBr endows it with the ability

to activate methanol leading to high activity for transesterifi-cation of ethylene carbonatewithmethanolTherefore the useof basic ionic liquid BrTBDPEG

150TBDBr as catalyst allows

the integration of cycloaddition as well as transesterificationas a single process

Basic ionic liquids choline hydroxide [ChOH] cholinemethoxide (ChOMe) and choline imidazolium (ChIm) havebeen synthesized and checked for their catalytic activity forthe production of biodiesel from soybean oil [118] Of allthe three ionic liquids choline hydroxide was found to givethe best results in terms of yield efficiency and recyclabilityAfter studying various reaction parameters 4 wt catalyst


+

+ +CH2OOCR1 CH3OOCR1

CH3OOCR2CH3OOCR3CH2OOCR3

CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18

dosage at a temperature of 60∘C was optimized to give thebest results when the ratio of methanol to soybean oil was9 1 (see Scheme 15)

Basic ionic liquid [bmim]OH has been successfully usedas an efficient catalyst for the synthesis of substituted ureasstarting from carbon dioxide and amines [119] The mainadvantages of thismethodology are solvent-free reaction con-ditions no need of dehydrating agents to remove the waterformed as a by-product recyclability of catalyst and oper-ational simplicity The developed protocol is quite generalas aliphatic amines cyclohexylamine and benzylamine wereconverted to corresponding ureas efficiently and selectively(see Scheme 16)

Various [DABCO] based ionic liquids have been screenedfor executing Knoevengeal condensation reaction [120] Ofall these ionic liquids [C

4dabco] [BF

4] was found to give the

best results Using [C4dabco] [BF

4] as catalyst in aqueous

media various aromaticaliphaticheterocyclic120572120573 unsatu-rated aldehydes and cyclicacyclic ketones have been foundto undergo efficient Knoevengeal condensation with active

methylene compounds No product purificationwas requiredand the catalyst was found to be recyclable up to sevencycles without any decrease in activity The reaction is highlystereoselective giving alkenes with E-geometry only (seeScheme 17)

43 As Organocatalysts In the last few years a renewed inter-est in the use of organic compounds as catalysts has begun toemerge Ionic liquids have the potential to have a huge impactin this area [121ndash124] One of the promising approaches toorganocatalysis is through hydrogen bonding interactionsand the reactions to which this has been most often appliedare Diels-Alder cycloadditions and their derivatives

Luo and coworkers used a functionalized chiral ionicliquid as an efficient reusable organocatalyst for asymmetricMichael addition of ketonesaldehydes with nitroalkenes[125] (see Scheme 18)

Pyrrolidine-based chiral ionic liquid has been developedby Ni and coworkers [126] This chiral ionic liquid wasfound to catalyze the Michael addition reaction of aldehydes


ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+

n = 1 X = NTf2n = 4 X = NTf2n = 8 X = NTf2n = 12 X = NTf2

IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21

and nitrostyrenes to give moderate yields good enantios-electivies high diastereoselectivities and recyclability (seeScheme 19)

Though ionic liquids are green solvents they are syn-thesized from the materials which use fossil fuels as theirresource Synthesizing ionic liquids from renewable rawmaterials will add to the green attributes of ionic liquidsSugars are suitable abundantly available raw material forthe synthesis of ionic liquids Also the presence of hydroxylgroups in the ionic liquids derived from sugars makes themhighly coordinating solvents thus enabling them to be usedin stereoselective and metal catalyzed reactions

Erfut et al synthesized novel hydrogen bond rich ionicliquids based on D-glucosopyranoside derivatives as cationprecursor and low coordinating bistriflimide as anion [127]Chloroalcohols have been utilized as source of hydroxyl

groups for the construction of ionic liquid cationThe synthe-sized ionic liquids were successfully used as organocatalysts(4mol with respect to dienophile) for Diels-Alder reactionof various dienes and dienophiles Influence of number ofhydroxyl groups on the reaction course has been thoroughlyinvestigatedWith all the ionic liquids the endo selectivitywasfound to be prevalent (see Scheme 20)

Starting from (S)-proline several chiral ionic liquids havebeen synthesized by Vasiloiu and coworkers [128] Theseionic liquids were successfully used as organocatalysts toexecute asymmetric aldol condensation giving good yieldsand selectivity up to 80 ee

It has been observed that hydrophilic triflimide basedchiral ionic liquids lead to greater yields and higher selec-tivities as compared to ionic liquids bearing methyl sulphateor bromide anions This methodology not only negates


PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH

[emim]Ac[emim]Ac PHCHO

CO2

Scheme 24

the requirement of corrosive trifluoroacetic acid but alsowidens the substrate scope for organocatalysis towards acidsensitive compounds (see Scheme 21)

Li et al synthesized a sulphur functionalized chiralionic liquid which has been used as an organocatalyst forepoxidation reaction of various aromatic aldehydes withbenzyl bromide in water giving trans-epoxides with highdiastereoselectivity and enantioselectivity up to 72 ee [129]Sodium carbonate has been found to be the best base forthis process Work-up of this reaction is quite simple as theorganocatalyst is insoluble in ether and soluble in water Thecatalytic system is recyclable up to five cycles without anyappreciable reduction in yields and enatioselectivities (seeScheme 22)

Imidazolium based ionic liquids can be used as pre-catalysts for N-heterocyclic carbene catalyzed reactionswhereby the catalyst can be obtained by deprotonation (seeScheme 23)

Kelemen and coworkers successfully used imidazoliumacetate as organocatalysts for benzoin condensation hydroa-cylation and oxidation of alcohols using carbon-dioxide andair [130] (see Scheme 24)

5 Ionic Liquids as Soluble Supports

Due to their tunable solubility and practically nonvolatilenature ionic liquids have been used as soluble supports forcatalystreagent immobilization [92] (see Figure 6) Ionic liq-uid supported synthesis (ILSS) has been successfully appliedfor a number of organic reactions like 13-cycloadditions [131]Knoevengeal reaction [60] Suzuki coupling [132] synthesisof thiazolidinones [133] oligosaccharide synthesis [134] andGriecorsquos multicomponnet synthesis of tetrahydroquinolines[135]

Donga and coworkers described the synthesis of oligonu-cleotides in solution using a soluble ionic liquid support


OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25

Substrate ReagentCatalyst

Liquid phase reaction

Product

Catalyst

+

+

+

minus

minus

(a)

ReagentLinkage Reagent Liquid-phase

reaction

Substrate

ProductOrganic phase

Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)

Substrate Linkage SubstrateLiquid-phase

reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent

Aqueous phaseInorganics

RepeatProductDetachmentphase separation

Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)

Figure 6 Ionic liquid supported synthesis (ILSS) (a) catalyst (b) reagent and (c) substrate [92]

Oligonucleotides up to tetrameric species have been synthe-sized and shown to be comparable to the products generatedusing standard automated DNA synthesis techniques [136](see Scheme 25)

A novel and efficient route using ionic liquids assoluble supports has been reported for the synthesisof 14-benzodiazepine-25-dione by Xie et al [137] (seeScheme 26)


OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion

This review is focused on the synthesis importance andapplications of ionic liquids Not particularily as solventsthey are nowadays finding use as catalysts and catalytic sup-ports in organic chemistry Their scope has marched beyondacademic research laboratories to industrieswhere their prac-tical applications have been leading to various sustainabletechnologies Flexibility to modulate properties by changingdesign endows freedom to a chemist to design an ionic liquidaccording to onersquos own requirement To conclude it can besaid that the field of ionic liquid catalysis holds enormouspossibilities to be explored

Conflict of Interests

The author declares that there is no conflict of interestsregarding the publication of this paper

References

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[2] D J Adams P J Dyson and S J Tavener Chemistry in Alter-native Reaction Media John Wiley amp Sons Chichester UK2004

[3] P Pollet E A Davey E E Urena-Benavides C A Eckert andC L Liotta ldquoSolvents for sustainable chemical processesrdquoGreenChemistry vol 16 no 3 pp 1034ndash1055 2014

[4] P Wassercheid and T Welton Ionic Liquids in Synthesis Wiley-VCH New York NY USA 2nd edition 2008

[5] T Welton ldquoRoom-temperature ionic liquids solvents for syn-thesis and catalysisrdquo Chemical Reviews vol 99 no 8 pp 2071ndash2083 1999

[6] C E Song ldquoEnantioselective chemo- and bio-catalysis in ionicliquidsrdquo Chemical Communications no 9 pp 1033ndash1043 2004

[7] Y Xiao and SVMalhotra ldquoDiels-Alder reactions in pyridiniumbased ionic liquidsrdquo Tetrahedron Letters vol 45 no 45 pp8339ndash8342 2004

[8] S T Handy ldquoGrignard reactions in imidazolium ionic liquidsrdquoJournal of Organic Chemistry vol 71 no 12 pp 4659ndash46622006

[9] S Anjaiah S Chandrasekhar and R Gree ldquoCarbon-Ferrierrearrangements in ionic liquids using Yb(OTf)

3as catalystrdquo

Journal of Molecular Catalysis A Chemical vol 214 pp 133ndash1362004

[10] P Mastrorilli C F Nobile R Paolillo and G P SurannaldquoCatalytic Pauson-Khand reaction in ionic liquidsrdquo Journal ofMolecular Catalysis A Chemical vol 214 no 1 pp 103ndash1062004

[11] M Lombardo M Chiarucci and C Trombini ldquoA recyclabletriethylammonium ion-tagged diphenylphosphine palladiumcomplex for the Suzuki-Miyaura reaction in ionic liquidsrdquoGreen Chemistry vol 11 no 4 pp 574ndash579 2009

[12] Z L Shen W J Zhou Y T Liu S J Ji and T P Loh ldquoOne-pot chemoenzymatic syntheses of enantiomerically-enrichedO-acetyl cyanohydrins from aldehydes in ionic liquidrdquo GreenChemistry vol 10 no 3 pp 283ndash286 2008

[13] L-C Feng Y-W Sun W-J Tang et al ldquoHighly efficientchemoselective construction of 22-dimethyl-6-substituted 4-piperidones via multi-component tandem Mannich reaction inionic liquidsrdquoGreen Chemistry vol 12 no 6 pp 949ndash952 2010

[14] D Singh S Narayanaperumal K Gul M Godoi O E DRodrigues and A L Braga ldquoEfficient synthesis of selenoesters


from acyl chlorides mediated by CuO nanopowder in ionicliquidrdquo Green Chemistry vol 12 no 6 pp 957ndash960 2010

[15] T Fukuyama T Inouye and I Ryu ldquoAtom transfer carbony-lation using ionic liquids as reaction mediardquo Journal of Orga-nometallic Chemistry vol 692 no 1ndash3 pp 685ndash690 2007

[16] A Schenzel A Hufendiek C Barner-Kowollik and M A RMeier ldquoCatalytic transesterification of cellulose in ionic liquidssustainable access to cellulose estersrdquo Green Chemistry vol 16no 6 pp 3266ndash3271 2014

[17] J Dupont R F de Souza and P A Z Suarez ldquoIonic liquid(molten salt) phase organometallic catalysisrdquoChemical Reviewsvol 102 no 10 pp 3667ndash3692 2002

[18] P Migowski and J Dupont ldquoCatalytic applications of metalnanoparticles in imidazolium ionic liquidsrdquo Chemistry vol 13no 1 pp 32ndash39 2007

[19] J Dupont G S Fonseca A P Umpierre P F P Fichtner andS R Teixeira ldquoTransition-metal nanoparticles in imidazoliumionic liquids recycable catalysts for biphasic hydrogenationreactionsrdquo Journal of the American Chemical Society vol 124no 16 pp 4228ndash4229 2002

[20] L Zhen Z Yingwei H Feng et al ldquoCatalysis and applicationsof task-specific ionic liquidsrdquo Scientia Sinica Chimica vol 4 pp502ndash524 2012

[21] P Walden ldquoUeber die Molekulargrosse und elektrischeLeitfahigkeit einiger geschmolzenen Salzerdquo Bulletin delrsquoAcademie Imperiale des Sciences de St-Petersbourg vol 8 no6 pp 405ndash422 1914

[22] H L Chum V R Koch L L Miller and R A Osteryoung ldquoAnelectrochemical scrutiny of organometallic iron complexes andhexamethylbenzene in a room temperaturemolten saltrdquo Journalof the American Chemical Society vol 97 no 11 pp 3264ndash32651975

[23] J S Wilkes ldquoA short history of ionic liquids - Frommolten saltsto neoteric solventsrdquo Green Chemistry vol 4 no 2 pp 73ndash802002

[24] P Wasserscheid and W Keim ldquoIonic liquidsmdashnew ldquosolutionsrdquofor transitionmetal catalysisrdquoAngewandte Chemie InternationalEdition vol 39 no 21 pp 3773ndash3789 2000

[25] F H Hurley and T P Wier ldquoElectrodeposition of metals fromfused quaternary ammonium saltsrdquo Journal ofThe Electrochem-ical Society vol 98 no 5 pp 203ndash206 1951

[26] J Robinson and R A Osteryoung ldquoAn electrochemical andspectroscopic study of some aromatic hydrocarbons in theroom temperature molten salt system aluminum chloride-n-butylpyridinium chloriderdquo Journal of the American ChemicalSociety vol 101 no 2 pp 323ndash327 1979

[27] J S Wilkes J A Levinsky R A Wilson and C L HusseyldquoDialkylimidazolium chloroaluminate melts a new class ofroom-temperature ionic liquids for electrochemistry spec-troscopy and synthesisrdquo Inorganic Chemistry vol 21 pp 1263ndash1264 1982

[28] Y Chauvin S Einloft and H Olivier ldquoCatalytic dimeriza-tion of propene by nickel-phosphine complexes in 1-butyl-3-methylimidazolium chlorideAlEtxCl3-x (x = 0 1) ionicliquidsrdquo Industrial and Engineering Chemistry Research vol 34no 4 pp 1149ndash1155 1995

[29] S D Williams J P Schoebrechts J C Selkirk and G Maman-tov ldquoA new room temperature molten salt solvent systemorganic cation tetrachloroboratesrdquo Journal of the AmericanChemical Society vol 109 no 7 pp 2218ndash2219 1987

[30] Y Chauvin and H O Bourbigou ldquoNonaqueous ionic liquids asreaction solventsrdquo Chemtech vol 25 no 9 pp 26ndash30 1995

[31] K R Seddon C Hardacre and B J McAuley ldquoCatalystcomprising indium salt and organic ionic liquid and process forfriedel-crafts reactionsrdquo WO 2003028883 2003

[32] J G Huddleston and R D Rogers ldquoRoom temperature ionicliquids as novel media for ldquocleanrdquo liquidmdashliquid extractionrdquoChemical Communications no 16 pp 1765ndash1766 1998

[33] J Fuller R T Carlin H C de Long andDHaworth ldquoStructureof 1-ethyl-3-methylimidazolium hexafluorophosphate modelfor room temperature molten saltsrdquo Journal of the ChemicalSociety Chemical Communications no 3 pp 299ndash300 1994

[34] L Cammarata S G Kazarian P A Salter and T WeltonldquoMolecular states of water in room temperature ionic liquidsrdquoPhysical Chemistry Chemical Physics vol 3 no 23 pp 5192ndash5200 2001

[35] J SWilkes andM J Zaworotko ldquoAir and water stable 1-ethyl-3-methylimidazoliumbased ionic liquidsrdquo Journal of the ChemicalSociety Chemical Communications no 13 pp 965ndash967 1992

[36] J D Holbrey and K R Seddon ldquoThe phase behaviour of1-alkyl-3-methylimidazolium tetrafluoroborates ionic liquidsand ionic liquid crystalsrdquo Journal of the Chemical Society DaltonTransactions no 13 pp 2133ndash2140 1999

[37] N L Lancaster T Welton and G B Young ldquoA study of halidenucleophilicity in ionic liquidsrdquo Journal of the Chemical SocietyPerkin Transactions 2 no 12 pp 2267ndash2270 2001

[38] P Bonhote A-P Dias N Papageorgiou K Kalyansundaramand M Gratzel ldquoHydrophobic highly conductive ambient-temperature molten saltsrdquo Inorganic Chemistry vol 35 no 5pp 1168ndash1178 1996

[39] D R MacFarlane S A Forsyth J Golding and G B DeaconldquoIonic liquids based on imidazolium ammonium and pyrroli-dinium salts of the dicyanamide anionrdquo Green Chemistry vol4 no 5 pp 444ndash448 2002

[40] A S Larsen J D Holbrey F S Tham and C A Reed ldquoDesign-ing ionic liquids Imidazolium melts with inert carborane ani-onsrdquo Journal of the American Chemical Society vol 122 no 30pp 7264ndash7272 2000

[41] M Hasan I V Kozhevnikov M R H Siddiqui A SteinerandNWinterton ldquoGold compounds as ionic liquids Synthesisstructures and thermal properties of NN1015840-dialkylimidazoliumtetrachloroaurate saltsrdquo Inorganic Chemistry vol 38 no 25 pp5637ndash5641 1999

[42] N D Khupse and A Kumar ldquoIonic liquids new materialswith wide applicationsrdquo Indian Journal of Chemistry Section AInorganic Physical Theoretical and Analytical Chemistry vol49 no 5-6 pp 635ndash648 2010

[43] P Domınguez de Marıa ldquoldquoNonsolventrdquo applications of ionicliquids in biotransformations and organocatalysisrdquoAngewandteChemie International Edition vol 47 no 37 pp 6960ndash69682008

[44] V Blasucci R Hart V L Mestre et al ldquoSingle componentreversible ionic liquids for energy applicationsrdquo Fuel vol 89 no6 pp 1315ndash1319 2010

[45] M Deetlefs and K R Seddon ldquoImproved preparations of ionicliquids using microwave irradiationrdquo Green Chemistry vol 5no 2 pp 181ndash186 2003

[46] J-M Leveque J-L Luche C Petrier R Roux and W BonrathldquoAn improved preparation of ionic liquids by ultrasoundrdquoGreenChemistry vol 4 no 4 pp 357ndash360 2002

[47] J-M Leveque S Desset J Suptil et al ldquoA general ultrasound-assisted access to room-temperature ionic liquidsrdquo UltrasonicsSonochemistry vol 13 no 2 pp 189ndash193 2006


[48] R S Varma and V V Namboodiri ldquoSolvent-free preparationof ionic liquids using a household microwave ovenrdquo Pure andApplied Chemistry vol 73 no 8 pp 1309ndash1313 2001

[49] R S Varma and V V Namboodiri ldquoAn expeditious solvent-freeroute to ionic liquids using microwavesrdquo Chemical Communi-cations no 7 pp 643ndash644 2001

[50] P D Vu A J Boydston and C W Bielawski ldquoIonic liquids viaefficient solvent-free anion metathesisrdquo Green Chemistry vol9 no 11 pp 1158ndash1159 2007

[51] J H Davis Jr K J Forrester and T Merrigan ldquoNovel organicionic liquids (OILS) incorporating cations derived from theantifungal drugmiconazolerdquoTetrahedron Letters vol 39 no 49pp 8955ndash8958 1998

[52] J H Davis Jr and K J Forrester ldquoThiazolium-ion based organicionic liquids (OILs) Novel oils which promote the benzoincondensationrdquo Tetrahedron Letters vol 40 no 9 pp 1621ndash16221999

[53] J H Davis Jr ldquoTask-specific ionic liquidsrdquo Chemistry Lettersvol 33 no 9 pp 1072ndash1077 2004

[54] A D Sawant D G Raut N B Darvatkar and M M SalunkheldquoRecent developments of task-specific ionic liquids in organicsynthesisrdquo Green Chemistry Letters and Reviews vol 4 no 1pp 41ndash54 2011

[55] H Xing T Wang Z Zhou and Y Dai ldquoNovel Broslashnsted-acidicionic liquids for esterificationsrdquo Industrial and EngineeringChemistry Research vol 44 no 11 pp 4147ndash4150 2005

[56] E D Bates R D Mayton I Ntai and J H Davis Jr ldquoCO2

capture by a task-specific ionic liquidrdquo Journal of the AmericanChemical Society vol 124 no 6 pp 926ndash927 2002

[57] A E Visser J D Holbrey and R D Rogers ldquoHydrophobic ionicliquids incorporating N-alkylisoquinolinium cations and theirutilization in liquid-liquid separationsrdquo Chemical Communica-tions no 23 pp 2484ndash2485 2001

[58] G R Feng J J Peng H Y Qiu J X Jiang L Tao and GQ Lai ldquoSynthesis of novel greener functionalized ionic liquidscontaining appended hydroxylrdquo Synthetic Communications vol37 no 16 pp 2671ndash2675 2007

[59] A E Visser R P Swatloski WM Reichert et al ldquoTask-specificionic liquids for the extraction of metal ions from aqueoussolutionsrdquo Chemical Communications no 1 pp 135ndash136 2001

[60] J Fraga-Dubreuil and J P Bazureau ldquoGrafted ionic liquid-phase-supported synthesis of small organic moleculesrdquo Tetra-hedron Letters vol 42 no 35 pp 6097ndash6100 2001

[61] S-G Li ldquoFunctionalized imidazolium salts for task-specificionic liquids and their applicationsrdquoChemical Communicationsno 10 pp 1049ndash1063 2006

[62] A Horvath ldquoMichael adducts in regioselective synthesis of N-substituted azolesrdquo Synthesis no 9 pp 1183ndash1189 1995

[63] H Itoh K Naka and Y Chujo ldquoSynthesis of gold nanoparticlesmodified with ionic liquid based on the imidazolium cationrdquoJournal of the American Chemical Society vol 126 no 10 pp3026ndash3027 2004

[64] Z Fei D Zhao R Scopelliti and P J Dyson ldquoOrganometalliccomplexes derived from alkyne-functionalized imidazoliumsaltsrdquo Organometallics vol 23 no 7 pp 1622ndash1628 2004

[65] D Zhao Z Fei T J Geldbach R Scopelliti G Laurenczyand P J Dyson ldquoAllyl-functionalised ionic liquids synthesischaracterisation and reactivityrdquoHelvetica Chimica Acta vol 88no 3 pp 665ndash675 2005

[66] T L Merrigan E D Bates S C Dorman and J H DavisJr ldquoNew fluorous ionic liquids function as surfactants in

conventional room-temperature ionic liquidsrdquo Chemical Com-munications no 20 pp 2051ndash2052 2000

[67] P Wassercheid B Drieszligen-Holscher R van Hal H C Steffersand J Zimmermann ldquoNew functionalised ionic liquids fromMichael-type reactionsmdasha chance for combinatorial ionic liq-uid developmentrdquo Chemical Communications no 16 pp 2038ndash2039 2003

[68] J D Holbrey M B Turner W M Reichert and R DRogers ldquoNew ionic liquids containing an appended hydroxylfunctionality from the atom-efficient one-pot reaction of 1-methylimidazole and acid with propylene oxiderdquo Green Chem-istry vol 5 no 6 pp 731ndash736 2003

[69] W Bao Z Wang and Y Li ldquoSynthesis of chiral ionic liquidsfrom natural amino acidsrdquo The Journal of Organic Chemistryvol 68 pp 591ndash593 2003

[70] T Welton ldquoIonic liquids in catalysisrdquo Coordination ChemistryReviews vol 248 no 21ndash24 pp 2459ndash2477 2004

[71] A K Chakraborti and S R Roy ldquoOn catalysis by ionic liquidsrdquoJournal of the American Chemical Society vol 131 no 20 pp6902ndash6903 2009

[72] X Li D Zhao Z Fei and L Wang ldquoApplications of function-alized ionic liquidsrdquo Science in China Series B Chemistry vol49 no 5 pp 385ndash401 2006

[73] D ZhaoMWu Y Kou and EMin ldquoIonic liquids applicationsin catalysisrdquo Catalysis Today vol 74 no 1-2 pp 157ndash189 2002

[74] V I Parvulescu and C Hardacre ldquoCatalysis in ionic liquidsrdquoChemical Reviews vol 107 no 6 pp 2615ndash2665 2007

[75] Z Fei T J Geldbach D Zhao and P J Dyson ldquoFrom dys-function to bis-function on the design and applications offunctionalised ionic liquidsrdquo Chemistry A European Journalvol 12 no 8 pp 2122ndash2130 2006

[76] T L Greaves and C J Drummond ldquoProtic ionic liquidsproperties and applicationsrdquo Chemical Reviews vol 108 no 1pp 206ndash237 2008

[77] L He G H Tao W S Liu W Xiong T Wang and Y KouldquoOne-pot synthesis of Lewis acidic ionic liquids for Friedel-Crafts alkylationrdquo Chinese Chemical Letters vol 17 pp 321ndash3242006

[78] F Dong C Jian G Kai S Qunrong and L Zuliang ldquoSynthesisof coumarins via pechmann reaction in water catalyzed byacyclic acidic ionic liquidsrdquo Catalysis Letters vol 121 no 3-4pp 255ndash259 2008

[79] K Qiao and C Yokoyama ldquoKoch carbonylation of tertiaryalcohols in the presence of acidic ionic liquidsrdquo Catalysis Com-munications vol 7 no 7 pp 450ndash453 2006

[80] G Pousse F L Cavelier L Humphreys J Rouden and JBlanchet ldquoBroslashnsted acid catalyzed asymmetric aldol reaction acomplementary approach to enamine catalysisrdquoOrganic Lettersvol 12 no 16 pp 3582ndash3585 2010

[81] X B Liu M Lu T T Lu and G L Gu ldquoFunctionalized ionicliquid promoted aza-michael addition of aromatic aminesrdquoJournal of the Chinese Chemical Society vol 57 no 6 pp 1221ndash1226 2010

[82] R Turgis J Estager M Draye V Ragaini W Bonrath andJ-M Leveque ldquoReusable task-specific ionic liquids for a clean 120576-Caprolactam synthesis under mild conditionsrdquo ChemSusChemvol 3 no 12 pp 1403ndash1408 2010

[83] J Shen H Wang H Liu Y Sun and Z Liu ldquoBronsted acidicionic liquid as dual catalyst and solvent for environmentallyfriendly synthesis of Chalconerdquo Journal of Molecular CatalysisA Chemical vol 280 no 1-2 pp 24ndash28 2008


[84] A C Chaskar S R Bhandari A B Patil O P Sharma andS Mayeker ldquoSolvent-free oxidation of alcohols with potassiumpersulphate in the presence of bronsted acidic ionic liquidsrdquoSynthetic Communications vol 39 no 2 pp 366ndash370 2009

[85] W Wang L Shao W Cheng J Yang and M He ldquoKoch car-bonylation of tertiary alcohols in the presence of acidic ionicliquidsrdquo Catalysis Communications vol 7 no 7 pp 450ndash4532006

[86] J C S Ruiz J M Campelo M Francavilla et al ldquoEfficientmicrowave-assisted production of furfural from C

5sugars in

aqueous media catalysed by Bronsted acidic ionic liquidsrdquoCatalysis Science amp Technology vol 2 no 9 pp 1828ndash1832 2012

[87] L Zhang M Xian Y He et al ldquoA Broslashnsted acidic ionic liquidas an efficient and environmentally benign catalyst for biodieselsynthesis from free fatty acids and alcoholsrdquo Bioresource Tech-nology vol 100 no 19 pp 4368ndash4373 2009

[88] D Patil D Chandam A Mulik et al ldquoNovel Broslashnsted acidicionic liquid ([CMIM][CF

3COO]) prompted multicomponent

hantzsch reaction for the eco-friendly synthesis of acridine-diones an efficient and recyclable catalystrdquoCatalysis Letters vol144 no 5 pp 949ndash958 2014

[89] L He S Qin T Chang Y Sun and J Zhao ldquoGeminal broslashnstedacid ionic liquids as catalysts for themannich reaction in waterrdquoInternational Journal of Molecular Sciences vol 15 no 5 pp8656ndash8666 2014

[90] H Zhang F Xu X Zhou G Zhang and C Wang ldquoA Broslashnstedacidic ionic liquid as an efficient and reusable catalyst systemfor esterificationrdquo Green Chemistry vol 9 no 11 pp 1208ndash12112007

[91] S Das M Rahman D Kundu A Majee and A Hajra ldquoTask-specific ionic-liquid-catalyzed efficient synthesis of indolederivatives under solvent-free conditionsrdquo Canadian Journal ofChemistry vol 88 no 2 pp 150ndash154 2010

[92] W Miao and T H Chan ldquoIonic-liquid-supported synthesis anovel liquid-phase strategy for organic synthesisIonic-liquid-supported synthesis a novel liquid-phase strategy for organicsynthesisrdquo Accounts of Chemical Research vol 39 no 12 pp897ndash908 2006

[93] Z-W Wang and L-S Wang ldquoFriedelndashCrafts phosphylationof benzene catalyzed by [trEHAm]Cl-XAlCl

3ionic liquidsrdquo

Applied Catalysis A General vol 262 no 1 pp 101ndash104 2004[94] C Wang W Zhao H Li and L Guo ldquoSolvent-free synthesis of

unsaturated ketones by the Saucy-Marbet reaction using simpleammonium ionic liquid as a catalystrdquo Green Chemistry vol 11no 6 pp 843ndash847 2009

[95] A Brandt J Grasvik J P Hallett and T Welton ldquoDecon-struction of lignocellulosic biomass with ionic liquidsrdquo GreenChemistry vol 15 no 3 pp 550ndash583 2013

[96] A Brandt M J Ray T Q To D J Leak R J Murphy and TWelton ldquoIonic liquid pretreatment of lignocellulosic biomasswith ionic liquid-water mixturesrdquo Green Chemistry vol 13 no9 pp 2489ndash2499 2011

[97] A S Amarasekara and O S Owereh ldquoHydrolysis and decom-position of cellulose in bronOslashsted acidic ionic liquids undermild conditionsrdquo Industrial amp Engineering Chemistry Researchvol 48 no 22 pp 10152ndash10155 2009

[98] C Li and Z K Zhao ldquoEfficient acid-catalyzed hydrolysis ofcellulose in ionic liquidrdquo Advanced Synthesis and Catalysis vol349 no 11-12 pp 1847ndash1850 2007

[99] M E Zakrzewska E B Lukasik and R B Lukasik ldquoIonicliquid-mediated formation of 5-hydroxymethylfurfuralmdasha promising biomass-derived building blockrdquo ChemicalReviews vol 111 pp 397ndash417 2011

[100] T Stahlberg W Fu J M Woodley and A Riisager ldquoSynthesisof 5-(hydroxymethyl)furfural in ionic liquids paving the way torenewable chemicalsrdquoChemSusChem vol 4 no 4 pp 451ndash4582011


5sugars in

aqueous media catalysed by Bronsted acidic ionic liquidsrdquoCatalysis Science and Technology vol 2 pp 1828ndash1832 2012

[102] Z Sun M Cheng H Li et al ldquoOne-pot depolymerization ofcellulose into glucose and levulinic acid by heteropolyacid ionicliquid catalysisrdquo RSC Advances vol 2 no 24 pp 9058ndash90652012

[103] H Ren Y Zhou and L Liu ldquoSelective conversion of cellulose tolevulinic acid via microwave-assisted synthesis in ionic liquidsrdquoBioresource Technology vol 129 pp 616ndash619 2013

[104] A Taheri C Liu B Lai C Cheng X Pan and Y Gu ldquoBroslashnstedacid ionic liquid catalyzed facile synthesis of 3-vinylindolesthrough direct C3 alkenylation of indoles with simple ketonesrdquoGreen Chemistry vol 16 no 8 pp 3715ndash3719 2014

[105] E J Garcıa-Suarez S G Khokarale O N van Buu RFehrmann and A Riisager ldquoPd-catalyzed ethylene methoxy-carbonylation with Broslashnsted acid ionic liquids as promoter andphase-separable reaction mediardquo Green Chemistry vol 16 no1 pp 161ndash166 2014

[106] K Titze-Frech N Ignatiev M Uerdingen P S Schulz and PWasserscheid ldquoHighly selective aromatic alkylation of phenoland anisole by using recyclable broslashnsted acidic ionic liquidsystemsrdquo European Journal of Organic Chemistry no 30 pp6961ndash6966 2013

[107] A RHajipour and F Rafiee ldquoBasic ionic liquids a short reviewrdquoJournal of the IranianChemical Society vol 6 no 4 pp 647ndash6782009

[108] B C Ranu and S Banerjee ldquoIonic liquid as catalyst and reactionmedium The dramatic influence of a task-specific ionic liquid[bmIm]OH in Michael addition of active methylene com-pounds to conjugated ketones carboxylic esters and nitrilesrdquoOrganic Letters vol 7 no 14 pp 3049ndash3052 2005

[109] L Yang L-W Xu W Zhou L Li and C-G Xia ldquoHighlyefficient aza-Michael reactions of aromatic amines and N-heterocycles catalyzed by a basic ionic liquid under solvent-freeconditionsrdquo Tetrahedron Letters vol 47 no 44 pp 7723ndash77262006

[110] H Zang M Wang B W Cheng and J Song ldquoUltrasound-promoted synthesis of oximes catalyzed by a basic ionic liquid[bmIm]OHrdquo Ultrasonics Sonochemistry vol 16 no 3 pp 301ndash303 2009

[111] E Kowsari and M Mallakmohammadi ldquoUltrasound promotedsynthesis of quinolines using basic ionic liquids in aqueousmedia as a green procedurerdquo Ultrasonics Sonochemistry vol 18pp 447ndash454 2011

[112] I Yavari and E Kowsari ldquoEfficient and green synthesis oftetrasubstituted pyrroles promoted by task-specific basic ionicliquids as catalyst in aqueous mediardquo Molecular Diversity vol13 no 4 pp 519ndash528 2009

[113] Z Deng J Guo L Qiu Y Zhou L Xia and F Yan ldquoBasic ionicliquids a new type of ligand and catalyst for the AGET ATRPof methyl methacrylaterdquo Polymer Chemistry vol 3 no 9 pp2436ndash2443 2012


[114] L-R Wen H-Y Xie and M Li ldquoA basic ionic liquid cat-alyzed reaction of benzothiazole aldehydes and 55-dimethyl-13-cyclohexanedione efficient synthesis of tetrahydrobenzo[b]pyransrdquo Journal of Heterocyclic Chemistry vol 46 no 5 pp954ndash959 2009

[115] J-M Xu Q Wu Q-Y Zhang F Zhang and X-F Lin ldquoBasicionic liquid as catalyst and reaction medium a rapid and facileprotocol for Aza-Michael addition reactionsrdquo European Journalof Organic Chemistry pp 1798ndash1802 2007

[116] L Wang H Li and P Li ldquoTask-specific ionic liquid as baseligand and reaction medium for the palladium-catalyzed Heckreactionrdquo Tetrahedron vol 65 no 1 pp 364ndash368 2009

[117] Z Z Yang Y N Zhao L N He J Gao and Z S Yin ldquoHighlyefficient conversion of carbon dioxide catalyzed by polyethyleneglycol-functionalized basic ionic liquidsrdquo Green Chemistry vol14 no 2 pp 519ndash527 2012

[118] M Fan J Huang J Yang and P Zhang ldquoBiodiesel productionby transesterification catalyzed by an efficient choline ionicliquid catalystrdquo Applied Energy vol 108 pp 333ndash339 2013

[119] T Jiang X Ma Y Zhou S Liang J Zhang and B Han ldquoSol-vent-free synthesis of substituted ureas from CO

2and amines

with a functional ionic liquid as the catalystrdquo Green Chemistryvol 10 no 4 pp 465ndash469 2008

[120] D-Z Xu Y Liu S Shi and Y Wang ldquoA simple efficient andgreen procedure for Knoevenagel condensation catalyzed by[C4dabco][BF

4] ionic liquid in waterrdquo Green Chemistry vol 12

no 3 pp 514ndash517 2010[121] F-L Yu R-L Zhang C-X Xie and S-T Yu ldquoSynthesis

of thermoregulated phase-separable triazolium ionic liquidscatalysts and application for Stetter reactionrdquo Tetrahedron vol66 no 47 pp 9145ndash9150 2010

[122] D Z Xu Y Liu S Shi and Y Wang ldquoChiral quaternaryalkylammonium ionic liquid [Pro-dabco][BF

4] as a recyclable

and highly efficient organocatalyst for asymmetric Michaeladdition reactionsrdquo Tetrahedron Asymmetry vol 21 no 20 pp2530ndash2534 2010

[123] O V Maltsev A S Kucherenko A L Chimishkyan and S GZlotin ldquo120572120572-Diarylprolinol-derived chiral ionic liquids recov-erable organocatalysts for the domino reaction between 120572120573-enals and N-protected hydroxylaminesrdquo Tetrahedron Asymme-try vol 21 no 21-22 pp 2659ndash2670 2010

[124] S S Khan J Shah and J Liebscher ldquoIonic-liquid taggedprolines as recyclable organocatalysts for enantioselective 120572-aminoxylations of carbonyl compoundsrdquo Tetrahedron vol 67no 10 pp 1812ndash1820 2011

[125] S Luo X Mi L Zhang S Liu H Xu and J-P ChengldquoFunctionalized chiral ionic liquids as highly efficient asym-metric organocatalysts for michael addition to nitroolefinsrdquoAngewandte Chemie International Edition vol 45 pp 3093ndash3097 2006

[126] B Ni Q Zhang and A D Headley ldquoFunctionalized chiral ionicliquid as recyclable organocatalyst for asymmetric Michaeladdition to nitrostyrenesrdquo Green Chemistry vol 9 no 7 pp737ndash739 2007

[127] K Erfut IWandzik KWalczak KMatuszek andA ChrobokldquoHydrogen-bond-rich ionic liquids as effective organocatalystsfor DielsndashAlder reactionsrdquo Green Chemistry vol 16 no 7 pp3508ndash3514 2014

[128] M Vasiloiu D Rainer P Gaertner C Reichel C Schroder andK Bica ldquoBasic chiral ionic liquids a novel strategy for acid-freeorganocatalysisrdquoCatalysis Today vol 200 no 1 pp 80ndash86 2013

[129] J Li X-K Xie F Liu and Z-Z Huang ldquoSynthesis of new func-tionalized chiral ionic liquid and its organocatalytic asymmetricepoxidation in waterrdquo Catalysis Communications vol 11 pp276ndash279 2009

[130] Z Kelemen O Holloczki J Nagy and L Nyulaszi ldquoAn organ-ocatalytic ionic liquidrdquo Organic amp Biomolecular Chemistry vol9 pp 5362ndash5364 2011

[131] J F Dubreuil and J P Bazureau ldquoRate accelerations of 13-dipolar cycloaddition reactions in ionic liquidsrdquo TetrahedronLetters vol 41 no 38 pp 7351ndash7355 2000

[132] WMiao and T H Chan ldquoExploration of ionic liquids as solublesupports for organic synthesis demonstration with a suzukicoupling reactionrdquoOrganic Letters vol 5 no 26 pp 5003ndash50052003

[133] J Fraga-Dubreuil and J P Bazureau ldquoEfficient combinationof task-specific ionic liquid and microwave dielectric heatingapplied to one-pot three component synthesis of a small libraryof 4-thiazolidinonesrdquoTetrahedron vol 59 no 32 pp 6121ndash61302003

[134] J-Y HuangM Lei and Y-GWang ldquoA novel and efficient ionicliquid supported synthesis of oligosaccharidesrdquo TetrahedronLetters vol 47 no 18 pp 3047ndash3050 2006

[135] F Hassine S Gmouh M Pucheault and M Vaultier ldquoTaskspecific onium salts and ionic liquids as soluble supports inGriecorsquos multicomponent synthesis of tetrahydroquinolinesrdquoMonatshefte fur Chemie vol 138 no 11 pp 1167ndash1174 2007

[136] R A Donga S M Khaliq-Uz-Zaman T-H Chan and M JDamha ldquoA novel approach to oligonucleotide synthesis usingan imidazolium ion tag as a soluble supportrdquo Journal of OrganicChemistry vol 71 no 20 pp 7907ndash7910 2006

[137] H Xie C Lu G Yang and Z Chen ldquoSynthesis of 14-Ben-zodiazepine-25-diones using an ionic liquid as a Soluble Sup-portrdquo Synthesis vol 2009 no 2 pp 205ndash210 2009

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Carbohydrate Chemistry

International Journal of


Journal of

Chemistry


Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of


Chromatography Research International


Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


(1) +Metal salt M+[A]minus

minusMX (precipitation)(2) +Bronsted acid H+

[A]minus

minusHX (evaporation)(3) Ion exchange resin

Step I

Step IIa Step IIb+Lewis acid

MXy

+R998400X

NR3

[R998400R3N]+[MXyminus1]minus

[R998400R3N]+[A]minus

[R998400R3N]+Xminus

Figure 1 Synthesis path for the preparation of ionic liquids [24]

[emim]+Clminus + AlCl3 [emim]

+[AlCl4]

minus

[emim]+[AlCl4]

minus+ AlCl3 [emim]

+[Al2Cl7]

minus

[emim]+[Al2Cl7]

minus+ AlCl3 [emim]

+[Al3Cl10]

minus

(1)

(2)

(3)

Scheme 1 Series of equilibria in the reaction between [emim]Cl andAlCl3

Ionic liquids come in twomain categories namely simplesalts (made of a single anion and cation) and binary ionicliquids (salts where equilibrium is involved) For example[EtNH

3][NO3] is a simple salt whereas mixtures of alu-

minum(III) chloride and 13-dialkylimidazolium chlorides (abinary ionic liquid system) contain several different ionicspecies and their melting point and properties dependupon the mole fractions of aluminum(III) chloride and 13-dialkylimidazolium chloride present

The synthesis of ionic liquids can be described in twosteps (Figure 1)

(1) The Formation of the Desired Cation The desired cationcan be synthesized either by the protonation of the amine byan acid or through quaternization reactions of amine with ahaloalkane and heating the mixture

(2) Anion ExchangeAnion exchange reactions can be carriedout by treatment of halide salts with Lewis acids to formLewisacid-based ionic liquids or by anion metathesis

The most extensively studied and used Lewis acid basedionic liquids are AlCl

3based salts [25ndash27] Such salts involve

simple mixing of the Lewis acid and the halide salt whichresults in the formation of more than one anionic speciesdepending upon the ratio of quaternary halide salt Q+Xminusand Lewis acid MX

119899as illustrated by the reaction between

[emim]Cl and AlCl3in Scheme 1

When [emim]Cl is present in molar excess over AlCl3the

ionic liquid formed is basic (1) however the molar excessof AlCl

3leads to the formation of an acidic ionic liquid (3)

When both [emim]Cl and AlCl3are present in equimolar

quantities it results in the formation of neutral ionic liquidsApart from AlCl

3 other Lewis acids used are AlEtCl

2[28]

BCl3[29] CuCl [30] and InCl

3[31] to mention a few

Anion metathesis is the methodology of choice for thepreparation of water and air stable ionic liquids based upon

Table 1 Examples of ionic liquids prepared by anion metathesis

Salt Anion source References[Cation][PF6] HPF6 [32ndash34][Cation][BF4] HBF4 NH4BF4 NaBF4 [33ndash37][Cation][(CF3SO2)2N] Li[(CF3SO2)2N] [34 38][Cation][CF3SO3] CF3SO3CH3 NH4[CF3SO3] [38][Cation][CH3CO2] Ag[CH3CO2] [35][Cation][CF3CO2] Ag[CF3CO2] [35][Cation][CF3(CF3)3CO2] K[CF3(CF3)3CO2] [38][Cation][NO3] AgNO3 NaNO3 [34 38][Cation][N(CN)2] Ag[N(CN)2] [39][Cation][CB11H12] Ag[CB11H12] [40][Cation][AuCl4] HAuCl4 [41]

13-dialkylimidazolium cations This method involves thetreatment of the halide salt with the silversodiumpotassiumsalts of NO

2

minus NO3

minus BF4

minus SO4

2minus and CO2CH3

minus or with thefree acid of the appropriate anion Table 1 gives examples ofthe few ionic liquids prepared by anion metathesis

It is clear from the above discussion that large numberof ionic liquids can be envisioned by simple combination ofdifferent cations and anions The estimated number of singleILs is 1018 which further increases if we include binary andternary ionic liquids Because of their ldquotailor-maderdquo naturethe ionic liquids find applications as storage media for toxicgases catalystssolvents in organic syntheses performanceadditives in pigments and matrices [42ndash44]

Several new and improved methodologies using noncon-ventional techniques such as irradiation with microwaves(MW) and power ultrasound (US) whether used alone orin combination have considerably improved the synthesisof ILs cutting down reaction times and improving yields[45ndash47]The recent introduction of efficient solventless one-pot synthetic protocols should make ILs cheaper and thusencourage a wider use of these neoteric solvents [48ndash50]

3 Task Specific Ionic Liquids (TSILs)

In 1999 Davis Jr and Forrester demonstrated the concept ofdesigning ionic liquid to interact with a solute in a specificmanner by using a thiazolium based IL as a solvent-catalystfor the benzoin condensation and introduced the term ldquotaskspecific ionic liquidrdquo for such ILs in which functional group


N NRFG


+

-NH2


IL FG IL FG

TSIL

+

Figure 2

IonTSIL

exchange

= Nucleophile


Figure 3

HX H

R

OR

O+ ++


XminusXminus

Figure 4















NR NH

O

NR N

OH+

+

Xminus Xminus

Scheme 2

COOH

H

H

NNHO

H R

NEtBr NHO

H RNH2


+lowast lowast

Brminus

Scheme 3

NH

O

+


CH3SO3minus

Scheme 4

NHR

EWG

N N

NH

EWG

+

+

R1

SO3H

R1

Tsminus

Scheme 5












N N+

SO3H

[SBMI][HSO4]

N N+

SO3H

[SBMI][MeSO3]

N N+

SO3H

[SBMI][p-TsO]

N+

SO3H

[SBTA][p-TsO]

SO3H

[SBPP][p-TsO]

Ph

PhPh

P +

[SBP][p-TsO]

N+

SO3H

HSO4minus MeSO3

minus p-TsOminus


Figure 5


Scheme 6




3ionic




4


3NH] HSO

4gave the best









4] and

[C4C1im][MeSO








R1

R2OR3

OH

ILs R3O OR3

R1 = CH3


+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13


+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11









NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


N NRFG


+

-NH2


IL FG IL FG

TSIL

+

Figure 2

IonTSIL

exchange

= Nucleophile


Figure 3

HX H

R

OR

O+ ++


XminusXminus

Figure 4















NR NH

O

NR N

OH+

+

Xminus Xminus

Scheme 2

COOH

H

H

NNHO

H R

NEtBr NHO

H RNH2


+lowast lowast

Brminus

Scheme 3

NH

O

+


CH3SO3minus

Scheme 4

NHR

EWG

N N

NH

EWG

+

+

R1

SO3H

R1

Tsminus

Scheme 5












N N+

SO3H

[SBMI][HSO4]

N N+

SO3H

[SBMI][MeSO3]

N N+

SO3H

[SBMI][p-TsO]

N+

SO3H

[SBTA][p-TsO]

SO3H

[SBPP][p-TsO]

Ph

PhPh

P +

[SBP][p-TsO]

N+

SO3H

HSO4minus MeSO3

minus p-TsOminus


Figure 5


Scheme 6




3ionic




4


3NH] HSO

4gave the best









4] and

[C4C1im][MeSO








R1

R2OR3

OH

ILs R3O OR3

R1 = CH3


+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13


+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11









NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


NR NH

O

NR N

OH+

+

Xminus Xminus

Scheme 2

COOH

H

H

NNHO

H R

NEtBr NHO

H RNH2


+lowast lowast

Brminus

Scheme 3

NH

O

+


CH3SO3minus

Scheme 4

NHR

EWG

N N

NH

EWG

+

+

R1

SO3H

R1

Tsminus

Scheme 5












N N+

SO3H

[SBMI][HSO4]

N N+

SO3H

[SBMI][MeSO3]

N N+

SO3H

[SBMI][p-TsO]

N+

SO3H

[SBTA][p-TsO]

SO3H

[SBPP][p-TsO]

Ph

PhPh

P +

[SBP][p-TsO]

N+

SO3H

HSO4minus MeSO3

minus p-TsOminus


Figure 5


Scheme 6




3ionic




4


3NH] HSO

4gave the best









4] and

[C4C1im][MeSO








R1

R2OR3

OH

ILs R3O OR3

R1 = CH3


+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13


+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11









NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


N N+

SO3H

[SBMI][HSO4]

N N+

SO3H

[SBMI][MeSO3]

N N+

SO3H

[SBMI][p-TsO]

N+

SO3H

[SBTA][p-TsO]

SO3H

[SBPP][p-TsO]

Ph

PhPh

P +

[SBP][p-TsO]

N+

SO3H

HSO4minus MeSO3

minus p-TsOminus


Figure 5


Scheme 6




3ionic




4


3NH] HSO

4gave the best









4] and

[C4C1im][MeSO








R1

R2OR3

OH

ILs R3O OR3

R1 = CH3


+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13


+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11









NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


R1

R2OR3

OH

ILs R3O OR3

R1 = CH3


+ +R1

R2 O

2

Scheme 7

HN

HN

N

+

+

S

Solvent-free 60∘C

SO3H

CF3SO3

O

O O

minus

Scheme 8

CO R1 R1

Pd catalyst BAIL

R2OR2OH

O

+

Scheme 9

RO N N

O OR

RC6H13

C6H13


+ + +

+

HO3S

OTfminus

Scheme 10

N+

O

RCHO +

O

N

S

EtOH refluxO

OR

SCH2CN

H2N

[bmim]OH

Scheme 11









NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


NH EWG

R

NEWG

R[bmim]OH+

R1 R1

R2

EWG = CN COCH3

R998400

R998400

COOCH3

rt 10ndash20minR2

Scheme 12

X

R

HR

N

OH

OH


Pd(OAC)2 100∘C

+

+

(n-C4H9)3NBrminus

Scheme 13

Br

2

Br BrBr

BrBr

N

NN N

NNN

N N

N

N

N

N

N

H

N

NH

N

NH

H

HH

OO O

O

O

O

OO

OH HO

H3CO OCH3

CH3OH

PEG PEG

PEG

Basic ionic liquid


+

+++ +

+ ++

minusminus

minus

minusminus

minus

Brminus Brminus

Scheme 14











+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


+



CHOH

CH2CH2OHN

CH3OHCH2OH

CH2OHCHOOCR2

OHminus

Scheme 15

H2O2RNH2

N N

N N

O

OH

+

+

+R R

H HCO2

minus

Scheme 16

NN

CN

CN CN

CNO

+

+

RX

H

minus

Solvent rt

Scheme 17

O

Ph

PhO

NH

N N Bu+

+NO2

NO2X = Br BF4 PF6

Xminus

Scheme 18




4dabco] [BF










ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


ArH

O

N N S

O

ONH HN

H

O Ar

+

+

NO2

NO2R1

R1R2 R2

NTf2minus

Scheme 19

COOEt

COOEt

COOEt

COOEt

COOEtCOOEt+ +

+

OOOH

OHOH

N

HO[NTf2]

minus

Scheme 20

NH N

CnH2n+1

+

n = 1 X =

n = 4 X = Brn = 8 X = Brn = 12 X = Br

NH

NCnH2n+1

+


IL catalyst

O

O

O

H

O2NO2N

[CH2]n

[CH2]n

OH

+

XminusXminus

MeSO4minus

Scheme 21








PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


PhCHO PhCH2Br PhPh

H

H

S

OO

OMe

+

+N N

Na2CO3 H2O

Brminus

Scheme 22

N N

NN N

N

H H

Me Me MeAc

Ac

Et EtEt

AcH++

minus

∙∙

∙∙

Scheme 23

O

O

H2

OH

[emim]Ac

O

O

O

O

O

O

OH


CO2

Scheme 24









OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


OThyHO

O

O N N

O

O

O

OHO

O

BHO

OB

OH

P O+

minus

BF4n

Scheme 25



Product

Catalyst

+

+

+

minus

minus

(a)


reaction

Substrate


Reagentproduct

Regeneration+

+

+

minus minus

minus

(b)


reaction

Reagent

Reagentproduct

Organic solvent

Organic solvent



Recycle and reuse

Product

+

+

+

+

minus

minus

minus

minus

(c)





OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


OH

COOH

ClDCC DMAP

COO

ClCOO

N

H

BrBr

O

COO

NBr

ON

N

O

O

NOH = NOH

O2N

O2N

O2N

O2N

O2NCH2Cl2

R1NH2

R2NH2

R1

R1

R2

R1

Cu K2CO3CH3CN

+

+

BF4minus

Et3N CH2Cl2

Et3N CH2Cl2

Scheme 26

6 Conclusion




References










3as catalystrdquo





















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of















































































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of












































5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





5sugars in











3ionic liquidsrdquo










5sugars in





















2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of








2and amines







4] as a recyclable


























Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

Documents

Ionic Liquids: Synthesis and Applications in Catalysis