Tetrahedron Letters Vol. 54, Issue 15, 2013

Contents

COMMUNICATIONS

Organocatalytic enantioselective transient enolate protonation in conjugate addition of thioacetic acid toa-substituted N-acryloyloxazolidinones

pp 1911–1915

Rajshekhar A. Unhale, Nirmal K. Rana, Vinod K. Singh*

N

HHN

N

HN S

F3C CF3

R1N

O

O

O

R1N

O

O

O

AcSAcSH

1h (0.5 mol %)toluene, 0 °C

up to 97% ee

1h

up to 99% yield

Fast thiol–maleamic methyl ester addition for facile covalent cross-linking of oligonucleotides pp 1916–1920

Liqiang Cao, Zhen Xi*

Thermally driven asymmetric domino reaction catalyzed by a thermostable esterase and its variants pp 1921–1923

Reina Wada, Takashi Kumon, Robert Kourist, Hiromichi Ohta, Daisuke Uemura, Shosuke Yoshida, Kenji Miyamoto*

CH3

CO2EtCO2Et

Ar

CH3

ArH

CO2H

CH3

CO2EtCO2H

Ar

CH3

ArH

CO2EtHydrolysis Thermal Hydrolysis

Thermostable Esterase, 70°C, 48 h

decarboxylation

(S)-profens

Domino reaction

1901

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Synthesis of optically active 1,2,3-trisubstituted azetidines employing an organocatalytic approach with LL-proline pp 1924–1927

Marcela Amongero, Teodoro S. Kaufman*

R8

NH2

CHO+

R4

R7 R8

N

R4

OH

HN

(S)(R)

R4

R8

R7

R2

R3 R5

R6

R7R6

R5

R3

R2R3

R2

R5

R6

R1R1

Dendrowardols A and B, two new sesquiterpenoids from Dendrobium wardianum Warner pp 1928–1930

Wei-Wei Fan, Feng-Qing Xu, Fa-Wu Dong, Xiao-Nian Li, Xiao-Yong Wei, Jun Zhou, Jiang-Miao Hu*

1 2

H

H

OHHO

HH

OH

H

H

OHHO

HH

OH

A novel approach for the synthesis of hexaazaisowurtzitane derivatives pp 1931–1932

Sergey G. Il’yasov*, Maya V. Chikina

An efficient microwave-assisted enzyme-catalyzed regioselective synthesis of long chain acylated derivativesof flavonoid glycosides

pp 1933–1937

Ziaullah, H. P. Vasantha Rupasinghe*

O

O

O

OH

OH O

OHOH

OH

OH

OHOH

O

O

O

OH

OH O

OHOH

OH

OH

OHOR

+ H2O

OH

O

O

OH

OH

OH

OH

OH

OH

O

OH

O

O

OH

OH

OH

OR

OH

OH

O+ H2O

i, iii, ii

Our present investigation provides a facile, efficient, and economical method of microwave-assisted biocatalytic regioselective synthesis of long chain acylated derivatives ofisoquercitrin and phloridzin. (i) Acetone, 3 Å molecular sieves, Novozyme 435®, 45 �C; (ii) R = Oleic, Stearic, Linoleic, Linolenic, Eicosapentaenoic (EPA), Docosahexaenoic Acids(DHA), or their corresponding esters.

1902 Contents / Tetrahedron Letters 54 (2013) 1901–1909

2,5-Bis-(sulfonyl)pyrazines as unprecedented building blocks and their SNAr reactions pp 1938–1942

Jie Jack Li, Wei Meng, Shung Wu, Yong-Jin Wu, Jason Guernon, Martin P. Allen, Michael M. Miller*, Peter T. Cheng,Bang-chi Chen

N

NO2S

SO2

RR

N

N

SO2

R

X

R = Me, tBu, PhMe

X = O, S, NH

Y

N

N

SO2

R

NHN

HNBoc

Boc

N

N

SO2

R

N

N

N

SO2

RCO2Et

NMe

CO2Et

Hookerolides A–D, the first naturally occurring C17-pseudoguaianolides from Inula hookeri pp 1943–1946

Xiang-Rong Cheng, Jie Ren, Chun-Hui Wang, Bin Guan, Jiang-Jiang Qin, Shi-Kai Yan, Hui-Zi Jin*, Wei-Dong Zhang*

+0.078

−0.014

−0.030−0.058

−0.041

−0.068

−0.009

−0.025

−0.034

−0.012

−0.008

−0.043

−0.005 −0.054

−0.071

O O

O

O

H

OMTPA

O

13

16

17

−0.116-10

-5

0

5

10

15

20

200 250 300 350 400

CD [mdeg]

Wavelength [nm]

Hookerolide A

1R

16R

Samarium (II) iodide-induced intermolecular coupling of a,b-unsaturated esters with ketones: reactions of methylpropiolate and ethyl buta-2,3-dienoate with cyclohexanone and its application to synthesis of a terpene carboxylic acid

pp 1947–1950

Masakazu Sono, Natsuki Doi, Eri Yoshino, Sachiko Onishi, Daiki Fujii, Motoo Tori*

Cu-catalyzed decarboxylative coupling of propiolic acids with boronic acids pp 1951–1955

Leilei Shi, Wei Jia, Xun Li*, Ning Jiao*

BOH

OH

R1 R2

COOHR2

R1CuCl2.2H2O, BQ, Et3N,Pyridine

DCM, RT+

A mild procedure of Cu-catalyzed decarboxylative cross-coupling of aryl- and alkynyl-boronic acids for construction of unsymmetrical substitutedalkynes has been developed. The usage of inexpensive copper chloride as catalyst, and employing stable alkynl carboxylic acids and boronic acids as thesubstrates under oxidative conditions for sp–sp2 coupling, make this method very easy to operate.

Contents / Tetrahedron Letters 54 (2013) 1901–1909 1903

Organocatalytic enantioselective conjugate addition of 2-nitrocyclohexanone to acrylaldehyde: a concisetwo-step synthesis of chiral building block 1-azaspiro[4.5]decan-6-one

pp 1956–1959

Xiao-Hua Ding, Wei-Chen Cui, Xiang Li, Xuan Ju, Dan Liu, Shaozhong Wang, Zhu-Jun Yao*

NO2

O

+

O

H

HN

O(1S)-azaspiro[4.5]decan-6-one89% ee; 84% ee (gram-scale)

2 Steps

A three-component synthesis of benzochromenodiazocines and chromenopyridines pp 1960–1962

Zahra Dolatkhah, Mahnaz Nasiri-Aghdam, Ayoob Bazgir*

O

HN O

ORNH2O

O

CHO OHN

NR

O

O

COOR'

COOR'

O

O

NR

COOR'

COOR'

A one-pot, pseudo four-component synthesis of novel benzopyrano[2,3-b]pyridines under solvent-free conditions pp 1963–1966

Abolfazl Olyaei*, Mohsen Vaziri, Reza Razeghi

+CHO

Z+

CN

CN2

OHsolvent-free 110 oC

10 examples

YX

Z

W

X, Y, Z, W = H or OH

O N

NH2CN

NH2

ZHO

W

O N

NH2CN

NH2

Z

OHHO

or

Stereoselective synthesis of 1,2,3-triazolyl-functionalized isoxazolidines, via two consecutive 1,3-dipolarcycloadditions, as precursors of unnatural amino acids

pp 1967–1971

Kaïss Aouadi*, Sébastien Vidal, Moncef Msaddek, Jean-Pierre Praly

N

NO

O

COCH3

ON

N3

O

NHCH3R

CuI, i -Pr2NEt, 110 °CMW, 15 min

6 examples34 - 40% overall yield

COCH3

ON

N

O

NHCH3

NN

R

2 stepsN

O

ON

H

Br

98%

Br

1904 Contents / Tetrahedron Letters 54 (2013) 1901–1909

Sulfonated polypyrene (S-PPR) as efficient catalyst for esterification of carboxylic acids with equimolaramounts of alcohols without removing water

pp 1972–1975

Kiyoshi Tanemura*, Tsuneo Suzuki

SO3H

HO3S

SO3HHO3S

R1COOH+

R2OH

R1COOR2

S-PPR

+H2O

Studies on the preference of multiple coupling in the introduction of thiophene ring into poly-halogenatedaromatic compounds with nickel NHC catalyst

pp 1976–1979

Shota Tanaka, Go Tatsuta, Atsushi Sugie, Atsunori Mori*

+S

nHex

H

NN

NiCl Cl

PPhPh

Ph

NiCl2(PPh3)IPrBr Br

S

S

nHex

nHexBr

S

nHex

0%

+exclusively1.0 eq.

Studies towards the synthesis of montamine: synthesis of the 1,2-bis(indolyl)ethylhydrazine fragment pp 1980–1982

Lachlan M. Blair, Jonathan Sperry*

OMe

OH

N

O

HN

OH

MeO

HO

N

O

NH

HO

montamine NTs

N N

iPrO

TsN

OiPr

OOiPr

OiPrO

Rapid oxidation of organic halides with N-methylmorpholine N-oxide in an ionic liquid under microwaveirradiation

pp 1983–1986

Bannarak Khumraksa, Wong Phakhodee, Mookda Pattarawarapan*

Contents / Tetrahedron Letters 54 (2013) 1901–1909 1905

A direct route to 2,2,5-trisubstituted pyrrolidines of relevance to kaitocephalin pp 1987–1990

Nandkishkor Chandan, Mark G. Moloney*

Syntheses of p-terphenyls and 11,12-dihydroindeno[2,1-a]fluorene by one-pot benzannulation of Diels–Alderreactions of trans-1,2-dichloroethene and dienes

pp 1991–1993

Jinn-Hsuan Ho*, Yu-Chen Lin, Li-Ting Chou, Ying-Zhe Chen, Wei-Qi Liu, Chao-Li Chuang

sealedglass tube

> 240 oCoil-bath

R

+

R = OCH3, CH3, H, F, Cl, Br, CN11,12-Dihydro-

indeno[2,1-a]fluorene

Cl

Cl

R

N-arylation of heterocycles catalyzed by activated-copper in pure water pp 1994–1997

Qichao Yang, Yufang Wang, Dong Lin, Mingjie Zhang*

Ar-X + HN Cu(10%), LiOHH2O, 120 C

X=I, Br, Cl Yield: 23-90%

Ar N

Large and selective electrochemical response to fluoride by a tetrathiafulvalene-based sensor pp 1998–2000

Jing Xiong, Long Cui, Wei Liu, Jonathon E. Beves, Yu-Yang Li, Jing-Lin Zuo*

A new dual electro-optical fluoride sensor based on tetrathiafulvalene (TTF) generates the largest known electrochemical response to fluoride ions, a DE1/2 ofalmost 400 mV. The sensor is highly selective for fluoride over other anions, and displays ‘naked eye’ optical detection.

1906 Contents / Tetrahedron Letters 54 (2013) 1901–1909

A practical one-pot procedure for the synthesis of N–H isoquinolones pp 2001–2005

Shaonan Lu, Yingfu Lin, Hongban Zhong, Kang Zhao, Jianhui Huang*

2. NaH, 120 oC

NH

OOR1

R2R3

N

O

R2R3

Ar Ar

1. Pd(OAc)2 (10 mol%), NaI.2H2ONaOAc, DMF, 120 oC

H

17 examples yields up to 99%

Fast, solvent-free asymmetric alkynylation of prochiral sp3 C–H bonds in a ball mill for the preparation ofoptically active tetrahydroisoquinoline derivatives

pp 2006–2009

Jingbo Yu, Zhenhua Li, Kanyan Jia, Zhijiang Jiang, Menglu Liu, Weike Su*

NAr

R3 DDQ /L*Copper balls

NAr

R3

*

1 2

R1

R2H

19 examples yield up to 77%, ee up to 79%

ball millingN

N

OO

N

PhPh

L* = PyBox-1

R1

R2

R1, R2 = H, OMeR3 = Ar, Heteroaryl, alkyl,carboalkoxyl

Efficient oxidation of arylmethylene compounds using nano-MnO2 pp 2010–2013

Baskar Nammalwar, Chelsea Fortenberry, Richard A. Bunce*, Sathish Kumar Lageshetty, Kevin D. Ausman

A facile synthesis of tetracyclic benzo-pyridonaphthyridines by domino reaction pp 2014–2017

Vishnu Basetti, Rangarao Pallepati, Subramanya Hosahalli, Vijay Potluri*

N

CN

NH

F9a-m

N

R1

N NH

F

N

conc. H2SO4

10a-m

R1

Contents / Tetrahedron Letters 54 (2013) 1901–1909 1907

Synthesis of 3-benzazepines and azepino[4,5-b]heterocyclic ring systems via intramolecular Friedel–Craftscyclization

pp 2018–2021

Robert B. Kargbo*, Zohreh Sajjadi-Hashemi, Sujata Roy, Xiaomin Jin, R. Jason Herr

Bi(OTf)3 (20 mol%)4 Å mol. seives

solvent (0.05 M)rt, 16 h

NTsNTsR R

Br

Stereoselective total synthesis of (±)-hyperforin via intramolecular cyclopropanation pp 2022–2025

Masahiro Uwamori, Masahisa Nakada*

MeO

OMe

OTIPS

ON2

(±)-hyperforin

OOTIPS

MeO

O

OO

HO

OH

Highly Z-selective synthesis of a,b-unsaturated nitriles using the Horner–Wadsworth–Emmons reaction pp 2026–2028

Kaori Ando*, Miho Okumura, Shigeo Nagaya

1) base, THF

2) RCHO CNRZ

O

tBu

PCH2CNO

2

R = Arprim -alkylsec-alkyltert -alkyl

86-99% Z89-90% Z87-97% Z98->99% Z

basetBuOK, 18-crown-6NaHtBuOKtBuOK

Microwave assisted palladium catalyzed intermolecular a-arylation of copper-amide enolate of benzazepine pp 2029–2032

Amit Verma, Navneet Prajapati, Sujata Salecha, Rajani Giridhar, Mange Ram Yadav*

N Me

O

N Me

OPd, Ligand

Cu2I2, Base

N Me

OMe

NMeR

H ON Me

OMe Me

Traces

X

RR

Normal product

Abnormal products

1908 Contents / Tetrahedron Letters 54 (2013) 1901–1909

*Corresponding authorSupplementary data available via SciVerse ScienceDirect

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ISSN 0040-4039

Contents / Tetrahedron Letters 54 (2013) 1901–1909 1909