Chapter 3 Alkenes(1)

8/9/2019 Chapter 3 Alkenes(1)

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ORGANIC CHEMISTRY

CHM 207

CHAPTER 3:

ALKENES


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Subtopics

Nomenclature

Structures and

physical

properties

Preparation ofalkenes

Reactions of

alkenes

Addition

Combustion

Oxidation

Polimerization

Unsaturation

tests

Uses


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Also called olefins

Contain at least one carbon-carbon double bond

C=C)

General formula, Cn

H

2n

n=2,3,)

Classified as unsaturated hydrocarbons

compound with double or triple carbon-carbon

bonds that enable them to add hydrogen atoms.

sp2

-hybridized

For example:

C

2

H

4

- ethylene

CH2 CH2

ALKENES


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RULE 1. Select the longest continuous carbon chain that

contains a double bond.

This chain

contains 6 C

atoms

This chain

contains 8C atoms

- The chain contain 8 C, therefore, name the parent

compound octene.

correctwrong

RULE 2. Name this compound as you would an alkane, but

change

n

to

n

for an alkene.


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RULE 3. Number the carbon chain starting with the endnearer to the double bond.

Use the smaller numbes on the double-bonded carbon to

indicate the position of the double bond. Place this number

in front of the alkene name.

This end of the chain is closest to the

double bond. Begin numbering here.

1234

8

7

6

5

The name of the parent

compound is 1-octene.


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RULE 4. Branched chains and other groups are treated as innaming alkanes. Name the substituent group, and

designate its position on the parent chain with a number.

8

7

3 2 1

6

5

The ethyl group is attached to carbon 4.

4

4-ethyl-1-octene


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Placing numbers location of double bond) before the

part of the name n .

Example:

CH2 C CH2

H

Old naming system: 1-buteneNew naming system: but-1-ene

1 2 3 4CH3 C C CH2

H H

1 2 3 4CH2 CH35 6

Old naming system: 2-hexeneNew naming system: hex-2-ene

CH2 C C CH3H H

Old naming system: 3-methyl-1-buteneNew naming system: 3-methylbut-1-ene

1 2 4

CH3

CH3

3


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A compound with more than one double bond.

- Two double bond: diene

-Three double bond: triene

- Four double bond: tetraene

* Numbers are used to specify the locations of the double

bonds.

CH2 C C CH2H H

IUPAC names: 1,3-butadiene 1,3,5-heptatriene

new IUPAC names: buta-1,3-diene hepta-1,3,5-triene

1 2 3 4

CH3 C C C C C CH2

12347 6 5

H H H H H

1 23

47

6 5

8

IUPAC names: 1,3, 5, 7-cyclooctatetraene

new IUPAC names: cycloocta-1,3,5,7-tetraene


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Alkenes names as substituents are called

lk nyl

groups.

Can be named systematically as ethenyl, propenyl, etc.

or by common names such as vinyl, ally, methylene and

phenyl groups.

CH2 -CH=CH2

CHCHCH2CHCH2 CH2

CH=CH2

IUPAC name: 3-vinyl-1,5-hexadiene

-CH2-CH=CH2

methylene group(methylidene group)

vinyl group(ethenyl group)

3-methylenecyclohexene

New IUPAC name: 3-vinylhexa-1,5-diene

allyl group(2-propenyl group)


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Contains C=C in the ring

CH3 CH2CH31

2

34

5

6

1

23

4

5

1-methylcyclohexene 1,5-dimethylcyclopentene

12

34

5

6

IUPACname: 2-ethyl-1,3-cyclohexadieneNew IUPACname: 2-ethylcyclohexa-1,3-diene

cyclopropene cyclobutene cyclohexenecyclopentene

Nomenclature of cycloalkenes:- Similar to that alkenes

- Number the cycloalkane so that the double bond is between C1 and

C2 and so that the first substituent has as low a number as possible.

* Double bond always between C1 and C2.


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c is two particular atoms (or groups of atoms) are

adjacent to each other

t rans the two atoms (or groups of atoms) are

across from each other

C CH3C

H

CH2CH3

H

C CH3C

H

H

CH2CH3

cis-2-pentene trans-2-pentene


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i) boiling points and densities

ii)polarity


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- Most physical properties of alkenes are similar to thosealkanes.

- Example: the boiling points of 1-butene, cis-2-butene, trans-2-butene and n-butane are close to 0oC.

- Densities of alkenes: around 0.6 or 0.7 g/cm3.

- Boiling points of alkenes increase smoothly with molecularweight.

- Increased branching leads to greater volatility and lowerboiling points.

i. Boiling points and densities


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- relatively nonpolar.

- insoluble in water but soluble in non-polar solvents suchas hexane, gasoline, halogenated solvents and ethers.

- slightly more polar than alkanes because:

i) electrons in the pi bond is more polarizable(contributing to instantaneous dipole moments).

ii) the vinylic bonds tend to be slightly polar

(contributing to a permanent dipole moment).

ii. Polarity


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Alkyl groups are electron donating toward double bond,helping to stabilize it. This donating slightly polarizes thevinylic bond, with small partial positive charge on the alkyl

group and a small negative charge on the double bond carbonatom.

For example, propene has a small dipole moment of 0.35 D.

propene, = 0.35 D

C C

H3C

H

H

H

C C

H3C

H

CH3

H

C C

H3C

H

H

CH3

Vector sum =

propene, = 0.33 D

cis-2-butene, bp 4oC

Vector sum = 0

propene, = 0

trans-2-butene, bp 1oC

Vinylic bonds


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In a cis-disubstituted alkene, the vector sum of the two dipolemoments is directed perpendicular to the double bond.

In a trans-disubstituted alkene, the two dipole moments tend tocancel out. If an alkene is symmetrically trans-disubstituted, thedipole moment is zero.

Cis- and trans-2-butene have similar van der Waals attractions, butonly cis isomer has dipole-dipole attractions.

Because of its increased intermolecular attractions, cis-2-butenemust be heated to a slightly higher temperature (4oC versus 1oC)before it begins to boil.

C C

H3C

H

CH3

H

C C

H3C

H

H

CH3

Vector sum =

propene, = 0.33 D

cis-2-butene, bp 4oC

Vector sum = 0

propene, = 0

trans-2-butene, bp 1oC


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i) dehydration of alcohols

ii) dehydrohalogenation of haloalkanes


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Alkenes can be prepared in the following ways:

conc. H2SO4R-CH2-CH2-OH R-CH=CH2 + H2O

NaOH/ethanolR-CH

2

-CH2

-Xreflux R-CH=CH2 + HX

NaOH can be replaced by KOH

i. Dehydration of alcohols

ii. Dehydrohalogenation of haloalkanes


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Saytzeff rule:

- A reaction that produces an alkene would favour the

formation of an alkene that has the greatest number ofsubstituents attached to the C=C group.

CH3CH2-CH-CH3OH

H+

H+

CH3CH=CH-CH3 + H2O

CH3CH2-CH=CH2 + H2O

2-butanol2-butenemajor product

1-butene

CH3CH-CH-CH2

BrH H

KOH CH3CH=CH-CH3 CH3CH2CH=CH2alcohol

reflux

2-bromobutane2-butene(major product)

1-butene

Dehydration of alcohols

Dehydrohalogenation of haloalkanes


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Alkenes are more reactive than alkanes because:

i) A carbon-carbon double bond consists of a and a bond. It is

easy to break the bond while the bond remains intact.

ii) The electrons in the double bond act as a source of electrons(Lewis base). Alkenes are reactive towards electrophiles which

are attracted to the negative charge of the electrons.

iii) bond will broken, each carbon atom becomes an active site

which can form a new covalent bond with another atom. One bond is converted into 2 bonds.


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i) Addition reaction:

a) Addition of hydrogen (Catalytic hydrogenation)

b) Addition of halogens

- In inert solvent

- In water / aqueous medium

c) Addition of hydrogen halides

d) Addition reaction with concentrated sulfuric acid: hydration of

alkenes

e) Addition reaction with acidified water (H3O+): hydration of alkenes

ii) Combustion of alkenes

iii) Oxidation:a) Epoxidationb) Hydroxylationc) Ozonolysis

iv) Polymerization


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a) Addition of hydrogen (Catalytic hydrogenation):- hydrogenation: addition of H to a double bond and triple bond to

yield saturated product.

- alkenes will combine with hydrogen in the present to catalyst to

form alkanes.

C C H H C C

H H

Pt or Pd

25-90o

C

- Plantinum (Pt) and palladium (Pd) Catalysts

- Pt and Pd: temperature 25-90oC

- Nickel can also used as a catalyst, but a higher temperature of 140oC

200oC is needed.

i) Addition reaction


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H2C CH2 H2Pt

CH3CH2CH2CH2CH CH2 H2Pt

H3C CH3

CH3CH2CH2CH2CH2CH3

EXAMPLES:

ethylene ethanelow pressure

low pressurehexene hexane


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b) Addition of halogens:

i) In inert solvent:- alkenes react with halogens at room temperature and in dark.

- the halogens is usually dissolved in an inert solvent such as

dichloromethane (CH2Cl2) and tetrachloromethane (CCl4).

- Iodine will not react with alkenes because it is less reactive than

chlorine and bromine.

- Fluorine is very reactive. The reaction will produced explosion.

C C X X C C

X X

inert solvent

X X = halogen such as Br2or Cl2Inert solvent = CCl4or CH2Cl2


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EXAMPLES:

C CHH

H H Br Br

Br2

Br

Br

CCl4

CH3CH=CH2 Cl2CCl4

CH3CH

Cl

CH2

Cl

C C

Br

H H

Br

H Hinert solvent (CCl4)

ethene1,2-dibromoethane

* the red-brown colour of the bromine solution will fade and the

solution becomes colourless.

cyclohexene 1,2-dibromocyclohexane

propene 1,2-dichloropropane


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b) Addition of halogens:

ii) In water / aqueous medium:

- chlorine dissolves in water to form HCl and chloric (l) acid

(HOCl).

Cl2 (aq) + H2O(l) HCl(aq) + HOCl (aq)

- same as bromine

Br2 (aq) + H2O(l) HBr(aq) + HOBr(aq)

* Reaction of alkenes with halogens in water/ aqueous solution (eg.chlorine water and bromine water) produced halohydrins (an alcohol

with a halogen on the adjacent carbon atom).


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EXAMPLES:

CH3CH=CH2 + Br2H2O

CH3 CH

OH

CH2Br

CH3 CH

Br

CH2Br

1-bromo-2-propanol

(major product)

1,2-dibromopropane

(minor product)

propene

* Br atom attached to the carbon atom of the double bond which has the greater

number of hydrogen atoms.

CH3 CH2

1-chloro-2-butanol1-butene

CH3CH2CH=CH2 CH

OH

CH2

Cl

Cl2, H2O


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c) Addition of hydrogen halides:

- Addition reaction with electrophilic reagents.

- Alkenes react with hydrogen halides (in gaseous state or in aqueous

solution) to form addition products.

- The hydrogen and halogen atoms add across the double bond to

form haloalkanes (alkyl halides).

- General equation:

C C C C

H XHX

alkene haloalkane

- Reactivity of hydrogen halides : HF < HCl < HBr < HI


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* Reaction with HCl needs a catalyst such as AlCl3

H2C CH2 HCl AlCl3

CH3CH2Cl

H-I

CH3CH=CHCH3 + H-Br

I

CH3CH2CHCH3

Br

EXAMPLES:

cyclopentene iodocyclopentane

2-butene 2-bromobutane


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There are 2 possible products when hydrogen halides react with anunsymmetrical alkene.

It is because hydrogen halide molecule can add to the C=C bond in

two different ways.

C CH

HCH3H

H-I

C C

H

HCH3

H

H-I

C CH

HCH3H

H I

C C

H

HCH3

H

I H

1-iodopropane

2-iodopropane(major product)


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Markovnikovs rules:

- the addition of HX to an unsymmetrical alkene,the hydrogen atom adds to the carbon atom (ofthe double bond) that already has the greaternumber of hydrogen atoms.


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Step 2: Rapid reaction with a negative ion.

The negative ion (Y-) acts as nucleophile and attacks the positively

charged carbon atom to give product of the addition reaction.

C C

E

Y-

C C

E Y

Mechanism of electrophilic addition reactions:

- C=C : electron rich part of the alkene molecule

- Electrophiles: electron-seeking

Step 1: Formation of carbocation.

Attack of the pi bond on the electrophile to form carbocation.

C C C C

E

E Y Y-

carbocation

+ -


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CH3CH=CH2 HCl

CH3CHCH2

H Cl

CH3CHCH2

Cl H

1-chloropropane

2-chloropropane(major product)

according to Markovnikovsrules

123

Propene


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MECHANISM:

Step 1: Formation of carbocation

CCH H

HCH3H Cl CC

H HHC

H

HH

H

CC

H H

HCH

H

H H

or

less stable carbocation

(1o

carbocation)

more stable carbocation

(2o

carbocation)

Cl-

- 2o carbocation is more stable than 1o carbocation.

- 2o

carbocation tends to persist longer, making it more likely to combine with

Cl-

ion to form 2-chloromethane (basis of Markovnikov's rule).

CC

H H

HCH

H

H H

Cl-

Step 2: Rapid reaction with a negative ion

CC

H H

HCH

H

H HCl

2-chloromethane (major product)


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d) Addition reaction with concentrated sulfuric acid: hydration of

alkenes

- the alkene is absorbed slowly when it passed through

concentrated sulfuric acid in the cold (0-15oC).

- involves the addition of H atom and HSO4 group across the

carbon-carbon double bond.

- follows Markovnikovs rule.


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C C H

HH

H H OSO3H

(H2SO4)

CH3CH2OSO3H+H-OH

(H2O)

C C H

HH

H

H OSO3H

CH3CH2OH +H2SO4

ethyl hydrogensulphate

(CH3CH2HSO4)

When the reaction mixture is added to water and warmed,

ethyl hydrogensulphate is readily hydrolysed to ethanol

*ethene reacts with concentrated H2

SO4

to form ethanol*

or

*alkene reacts with concentrated H2SO4to form alcohol*


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e) Addition reaction with acidified water (H3O+): hydration of alkenes

Hydration: The addition of H atoms and OH groups from watermolecules to a multiple bond.

Reverse of the dehydration reaction.

Direct hydration of ethene:

- passing a mixture of ethene and steam over phosphoric (v) acid

(H3PO4) absorbed on silica pellets at 300oC and a pressure of 60

atmospheres.

- H3PO4 is a catalyst.

CH2=CH2 H2OH3PO4

CH3CH2OH(g) (g)

300

o

C, 60 atm

(g)

ethene ethanol

C C H2O C C

H OH

alkene alcohol

H+


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Markovnikovs rule is apply to the addition of a water molecule

across the double bond of an unsymmetrical alkene.

For examples:

CH3 C CH2

CH3

H OH H+

CH3CH=CH2 + H2O CH3CHCH3

OH

CH3 C CH2

CH3

OH H

25o

C2-methylpropene

tert-butyl alcohol

propene

2-propanol

H+

H+ = catalyst


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CCH H

HCH3

CC

H H

HCH

H

H H

H+

OH

H

CH3CHCH3

O H

H

CH3CHCH3

OH

CC

H H

HCH

H

H H

CH3CHCH3

O H

H

H+

MECHANISM OF ACID CATALYSED HYDRATION OF ALKENES

Step 1: Protonation to form carbocation

more stable carbocation

(2o

carbocation)

Step 2: Addition of H2O to form a protonated alcohol

Step 3: Loss of a proton (deprotonated) to form alcohol

H+ = catalyst


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When HBr is added to an alkene in the absence of peroxides it obey

Markovnikovs rule.

When HBr (not HCl or HI) reacts with unsymmetrical alkene in the

presence of peroxides (compounds containing the O-O group) or

oxygen, HBr adds in the opposite direction to that predicted byMarkovnikovs rule.

The product between propene and HBr under these conditions is 1-

bromopropane and not 2-bromopropane.

CH3CH=CH2 HBr CH3CH2CH2Brperoxide

1-bromopropane(major product)

anti-Markovnikovs orientation

ANTI-MARKOVNIKOVS RULE: FREE RADICAL

ADDITION OF HYDROGEN BROMIDE


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Anti-Markovnikovs addition:

- peroxide-catalysed addition of HBr occurs through afree radical addition rather than a polar electrophilicaddition.

- also observed for the reaction between HBr andmany different alkenes.

- not observed with HF, HCl or HI.


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Alkenes goes to hydroboration reaction to form anti-

Markovnikov alcohol.

C C

CH3 C

CH3

CH2

CH3CH=CH2

CH C

CH3

CH3CH3

B2H6

B2H6

B2H6

B2H6

C C

OHH

CH3 CH

CH3

CH2 OH

CH3CHCH2-OH

CH3CHCHCH3

OH

CH3

H2O2,-

OH

anti-markovnikov

examples:

H2O2, -

OH

propene propanol

H2O2,-

OH

isobutylene isobutyl alcohol

H2O2,-

OH

3-methyl-2-butanol

2-methyl-2-butene


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The alkenes are highly flammable and burn readily

in air, forming carbon dioxide and water.

For example, ethene burns as follows :

C2H4 + 3O2 2CO2 + 2H2O

ii) Combustion of alkenes


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Oxidation: reactions that form carbon-oxygen bonds.

Oxidation reaction of alkenes:

a) Epoxidation

b) Hydroxylationc) Ozonolysis

iii) Oxidation


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Epoxide / oxirane: a three-membered cyclic ether.

CH3 C

O

peroxyacetic acid

O O H C

O

peroxybenzoic acid

(PhCO3H)

O O H

m-chloroperoxybenzoic acid

(MCPBA)

Cl O

O

O

H

C CR C

O

O O H

O

C C R C

O

OH

alkene

peroxyacid epoxide (oxirane) acid

Examples of epoxidizing reagent:

a) Epoxidation of alkenes


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MCPBA

MCPBA

O

OCH2CI2, 25

oC

cyclohexene 1,2-epoxycyclohexane

CH2CI2, 25o

C

cycloheptene 1,2-epoxycycloheptane


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Hydroxylation:- Converting an alkene to a glycol requires adding a hydroxyl

group to each end of the double bond.

Hydroxylation reagents:

i) Osmium tetroxide (OsO4

)

ii)Potassium permanganate (KMnO4)

C C OsO4 H2O2 C C

OHOH(or KMnO4,-

OH)

glycol

b) Hydroxylation of alkenes


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CH CH2CH3

CH2 CH2 CH2 CH2

OH OH

CH2

OH

CHCH3

OH

MnO2

MnO2

KMnO4(aq), OH-

cold, dilute

ethene

1,2-ethanediol

KMnO4(aq), OH-cold, dilute

propene

1,2-propanediol

* Also known as Baeyers test


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Ozonolysis:- The reaction of alkenes with ozone (O3) to form an ozonide, followed byhydrolysis of the ozonide to produce aldehydes and /or ketone.

- Widely used to determine the position of the carbon-carbon double bond.

- Ozonolysis is milder and both ketone and aldehydes can be recoveredwithout further oxidation.

C C

R

R

R'

HO3 C

O OC

O R'

H

R

R

(CH3)2S

C O

R

RCO

R'

Hozonide ketone aldehyde

or H2O, Zn/H+

c) Ozonolysis of alkenes


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H

OCH3CH3O

H

H

O

OOCH3

H

O

CH3O

O

H

O

H

Oi) O3

ii) (CH3)2S3-nonene

i) O3

ii) (CH3)2S


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Polymer: A large molecule composed of many smaller repeating units(the monomers) bonded together.

Alkenes serves as monomers for some of the most common polymerssuch as polyethylene (polyethene), polypropylene, polystyrene,poly(vinyl chloride) and etc.

Undergo addition polymerization /chain-growth polymer:

- a polymer that results from the rapid addition of one molecule at atime to a growing polymer chain, usually with a reactive intermediate(cation, radical or anion) at the growing end of the chain.

iv) Polymerization of alkenes

C C

CI

H

H

H

C C

CI

H

H

H

C C

CI

H

H

H

C C

CI

H

H

H

C

H

H

C

Cl

H

C

H

H

C

Cl

Hn

poly(vinyl chloride)vinyl chloride

repeating unit


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POLYMER POLYMER USES MONOMER

FORMULA

POLYMER

REPEATING UNIT

Polyethylene Bottles, bags,

films

Polypropylene Plastics, olefin

fibers

Polystyrene Plastics, foam

insulation

Poly isobutylene) Specialized

rubbers

CH2=CH2 CH2 CH2 n

CH2 CH

CH3

n

C CH

H

CH3

H

CH2 C

CH3

CH3

nC CCH3

CH3

H

H

H2

C CH n

C C

H

H H


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i) Reactions of alkenes with KMnO4

ii) Reactions of alkenes with bromine.


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- KMnO4 is a strong oxidizing agent.

- alkenes undergo oxidation reactions with KMnO4

solution under two conditions:

a) Mild oxidation conditions using cold, dilute,

alkaline KMnO4 (Baeyers test).

b) Vigorous oxidation conditions using hot,acidified KMnO4.

UNS TUR TION TESTS FOR LKENES

i) Reaction of alkenes with KMnO4


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a) Reaction of alkenes with cold, dilute, alkaline KMnO4 (Baeyerstest)

- the purple colour of KMnO4 solution disappears and a cloudybrown colour appears caused by the precipitation of manganese(IV) oxide, MnO2.

- test for carbon-carbon double or triple bonds.

- a diol is formed (containing two hydroxyl groups on adjacent

carbon atoms).

C C C C

O H O H

M nO 2K M n O 4 (aq), OH

-

cold, d ilute

a diol


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- A solution of bromine in inert solvent (CH2

CI2

or CCI4

) and dilutebromine water are yellow in colour.

- The solution is decolorised when added to alkenes or organiccompounds containing C=C bonds.

C C Br2 CH 2CI 2

C C Br2(aq) H2O

C C

Br Br

C C

O H B r

C C

Br Br

ii) Reaction of alkenes with bromine


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a) Ozonolysis of alkenes:

- For example, ozonolysis of an alkene produces

methanal and propanone.

C O

methanal

HH CO CH3

CH3

propanone

C

H

H C CH3

CH3

CC CH3

CH3H

H

remove the oxygen atoms from the carbonyl compounds and

joining the carbon atoms with a double bond.

2-methylpropene

DETERMIN TION OF THE POSITION OF THE

DOUBLE BOND


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b) Reaction of alkenes with hot, acidified KMnO4

- by using hot, acidified KMnO4, the diol obtained isoxidised further.

- cleavage of carbon-carbon bonds occurs and the finalproducts are ketones, carboxylic acids or CO2.

KMnO4/H+

C CH2

CH3

CH3C O

CH3

CH3 CO2 + H2O2-methylpropene

propanone

(ketone)


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Example:

An alkene with the molecular formula C6H12 is oxidised with hot

KMnO4 solution. The carboxylic acids, butanoic acid(CH3CH2CH2COOH) and ethanoic acid (CH3COOH), are produced.

Identify the structural formula of the alkene.

C C

H

R

H

R'

CH3CH2CH2COOH and CH3COOH

C O

OH

R CO

OH

R'

CH3CH2CH2CH=CHCH3

KMnO4/H+

i) cleavage of the double bond gives a mixture of carboxylic acids

ii) location of the double bond is done by taking away the oxygen atoms from the

carboxylic acids and then joining the carbon atoms by the double bond.

RCOOH and R'COOH RCH=CHR'

butanoic acid ethanoic acid 2-hexene


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C CR

R''

R'

HC C H

R'R

OH

R''

OH

KMnO4/H+

C O

R

R'' COH

R'C O

R

R'' CO OH

R'

ketone acid ketone aldehyde

Example:

KMnO4/H+

CO

O

CHO

4-methyl-4-octene 2-pentanone butanoic acid

R CH=CH2KMnO4/H

+

R COOH + CO2+ H2O


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i) PE

ii) PVC

iii) ethanol


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Ethylene and propylene are the largest-volume industrial organic

chemicals. Used to synthesis a wide variety of useful compounds.

CH3 C

O

OH

CH2 CH2

CI CI

Cl2C C

H

H

H

H

CH3 C

O

H

O2

C C

CIH

H H

CH3 CH2

OH

NaOH

C C

H H

HH

H+

H2O

CH2 CH2

OHOH

O

H2C CH2

n

polyethylene

polymerize

acetaldehyde

oxidize

oxidize

acetic acid

ethylene ethylene dichloride

vinyl chloride

H2O

catalyst

Ag catalystethylene oxide

ethylene glycol ethanol

USES OF LKENES


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The most popular plastic.

Uses:

i) Grocery bags

ii)Shampoo bottlesiii)Children's toy

iv)Bullet proof vests

v)Film wrapping

vi)Kitchenware

i) POLYETHENE (PE)


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ii) POLYVINYL CHLORIDE (PVC)

C C

H H

CIH C C

H

H

CI

HC

H

HC

CI

HCH

H

C

CI

Hnvinyl chloride

polymerize

poly(vinyl chloride)PVC, "vinyl"

USES OF PVC:

Clothing- PVC fabric has a sheen to it and is waterproof.

- coats, shoes, jackets, aprons and bags.

As the insulation on electric wires.

Producing pipes for various municipal and industrial applications.For examples, for drinking water distribution and wastewater mains.

As a composite for the production of accessories or housings forportable electronics.

used in the building industry as a low-maintenance material.

Ceiling tiles.


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USE OF ETHANOL: Motor fuel and fuel additive. As a fuel to power Direct-ethanol fuel cells (DEFC) in order to produce

electricity. As fuel in bipropellant rocket vehicles. In alcoholic beverages.

An important industrial ingredient and use as a base chemical for otherorganic compounds include ethyl halides, ethyl esters, diethyl ether,acetic acid, ethyl amines and to a lesser extent butadiene.

Antiseptic use. An antidote.

Ethanol is easily miscible in water and is a good solvent. Ethanol is less

polar than water and is used in perfumes, paints and tinctures. Ethanol is also used in design and sketch art markers. Ethanol is also found in certain kinds of deodorants.

Documents

Chapter 3 Alkenes(1)