A2 ChemistryChapter 1

Chapter 1 Objectives

Electrophilic addition

Nucleophilic addition Reactions of Alcohols

Reactions of halogenoalkanes

Reactions of Alkenes

Optical isomers

Isomers

A2: Chains and Rings Revisited Chapter 1 Objectives

1.1. Describe and explain structural isomerism in compounds with the Describe and explain structural isomerism in compounds with the same molecular formula but different structural formula.same molecular formula but different structural formula.

2.2. Describe and explain cis-trans isomerism in alkenes, in terms of Describe and explain cis-trans isomerism in alkenes, in terms of restricted rotation about a double bond.restricted rotation about a double bond.

3.3. Determine the possible structural and/or cis-trans isomers of an Determine the possible structural and/or cis-trans isomers of an organic molecule of given molecular formula.organic molecule of given molecular formula.

4.4. Describe and explain optical isomerism arising from molecules with Describe and explain optical isomerism arising from molecules with a chiral centre.a chiral centre.

5.5. Recall from Chemistry 1, the chemical reactions of alkanes, Recall from Chemistry 1, the chemical reactions of alkanes, alkenes, alcohols and halogenoalkanes.alkenes, alcohols and halogenoalkanes.

6.6. Show knowledge and understanding of the following reaction Show knowledge and understanding of the following reaction mechanisms: free radical, substitution, electrophilic addition, mechanisms: free radical, substitution, electrophilic addition, nucleophilic additionnucleophilic addition

– Nomenclature should follow IUPAC rules for naming of organic compounds. For example, 3 Nomenclature should follow IUPAC rules for naming of organic compounds. For example, 3 methylpentane for CHmethylpentane for CH33CHCH22CH(CHCH(CH33)CH)CH22CHCH33..

Draw and name all possible isomers for the molecular formula: C4H8O2

H3CH2C

H2C C

O

OH

H3CH2C

HC

HC O

OH

H3CHC

H2C

HC O

OH

H2CH2C

H2C

HC O

OH

H2CH2C C CH3

OH

O

H3CH2C C CH2

O

OH

H3CHC C CH3

O

OH

H3CHC C

O

OH

CH3

H3C C CH

OH

CH3

O

1-hydroxy butan-2-one

Butanoic acid

4-hydroxy butan-2-one

3-hydroxy butanal

4-hydroxy butanal

2-hydroxy butanal

2-hydroxy butan-2-one

2-methyl propanoic acid

2-methyly,2-hydroxy propanal

Electrophilic addition

HBr to any C=C double bond

Nucleophilic substitution

Nucleophile to any C-Br bond

CH3CH2OHethanol

Name?Name?

combustion

Products?Products?

Na metal •Ethanoic acid•H+ catalyst•reflux

•Distil with:•Sulphuric acid•dichromate

CO2 + H2O

CH3CH2O-Na+ + H2Sodium Ethoxide

CH3COOCH2CH3 + H2O

Ethyl ethanoate

EthanalCH3CHO

•Reflux with:•Excess Sulphuric acid•dichromate

CH3COOH

Ethanoic acid

•Dehydration with hot Al2O3

CH2=CH2 + H2O

Ethene

•HBr in situ with conc H2SO4 + NaBr

CH3CH2BrBromoethane

Reactions of AlcoholsReactions of Alcohols

CH3CH2Brbromoethane

Name?Name?Products?Products?•Hot ethanolic NaOH

CH2=CH2

Ethene

•Excess alcoholic ammonia under pressure

CH3 CH2 NH2

Ethylamine

•Hydrolysis: OH-

(aq) or H2O

CH3CH2OHethanol

Reactions of HalogenoalkanesReactions of Halogenoalkanes

CH2=CH2ethene

Name?Name?Products?Products?

+ Br2

+ HBr

H2O(g) + phosphoric acid catalyst

CH2BrCH2Br

1,2-dibromoethane

CH3CH2Brbromoethane Ethanol

CH3CH2OH

Addition polymerisation -(-CH2-CH2-)-n

Polythene

H2(g) + Ni catalyst

CH3CH3

Ethane

Reactions of AlkenesReactions of Alkenes(ethene)(ethene)

HC

H2C

C

CH2

C

O

CH3

H2C CH3

H

HC

H2C

C

CH2

C

O

CH3

H2C CH3

H

HC

H2C

CH

CH2

C

O

CH3

H2C CH3

Optical Isomers

Carvone

One form produces the flavours of spearmint and the other the flavours of caraway.

Use the molymod kits to build a representation of carvone.

Chiral centre