Organic synthesis mechanisms + reagents

A level chemistry AQA

Alkane → alkene process

cracking

Catalytic cracking conditions

Temperature = 500C, catalyst = zeolite

Thermal cracking conditions

Temperature = 450-750C, pressure = 70 atm

Alkane → haloalkane reaction

Free radical substitution

Free radical substitution conditions

UV light

Alkene → haloalkane mechanism

Electrophilic addition

Alkene → haloalkane conditions

Room temperature

Alkene → haloalkane reagent

hydrogen halide

Alkene → alkyl hydrogensulphate mechanism

electrophilic addition

Alkene → alkyl hydrogensulphate reagents

concentrated sulfuric acid

Alkene → addition polymer reaction

polymerisation

Alkene → addition polymer conditions

High pressure + catalyst

Alkene → alcohol mechanism

Electrophilic addition

Alkene → alcohol conditions

Temperature = 300C, pressure = 60 atm, reaction carried on solid silica surface

Alkene → alcohol reagents

Steam + H⁺ from concentrated phosphoric acid

Haloalkane → alkene mechanism

Elimination

Haloalkane → alkene reagents

Hot ethanolic solution, KOH

Haloalkane → alcohol mechanism

Nucleophilic substitution

Haloalkane → alcohol reagents

aqueous KOH/NaOH

Haloalkane → alcohol conditions

heat under reflux

Haloalkane → nitrile mechanism

Nucleophilic substitution

Haloalkane → nitrile reagents

KCN, hot ethanolic solution

Haloalkane → nitrile conditions

heat under reflux

Haloalkane → 1^o amine mechanism

Nucleophilic substitution

Haloalkane → 1^o amine reagents

concentrated ammonia, ethanolic solution

Haloalkane → 1^o amine conditions

heat under pressure

Alkyl hydrogen sulphate → alcohol reaction

hydrolysis

Alkyl hydrogen sulphate → alcohol reagents + conditions

water and warm

1^o alcohol → aldehyde reaction

oxidation

1^o alcohol → aldehyde reagents

potassium dichromate, concentrated sulphuric acid

1^o alcohol → aldehyde conditions

Distillation

1^o alcohol → carboxylic acid reaction

oxidation

1^o alcohol → carboxylic acid reagents

potassium dichromate, concentrated sulphuric acid

1^o alcohol → carboxylic acid conditions

heat under reflux

2^o alcohol → ketone reaction

oxidation

2^o alcohol → ketone reagents

potassium dichromate, concentrated sulphuric acid

2^o alcohol → ketone conditions

heat under reflux

Alcohol → alkene mechanism

elimination

Alcohol → alkene reagents

H⁺ from concentrated sulphuric acid

Aldehyde/ketone → hydroxynitrile mechanism

Nucleophilic addition

Aldehyde/ketone → hydroxynitrile reagents

KCN, dilute sulphuric acid

Aldehyde/ketone → alcohol mechanism

Nucleophilic addition

Aldehyde/ketone → alcohol reagents

H^- from NaBH₄

Aldehyde → alcohol reaction

reduction

Aldehyde → alcohol reagents

NaBH₄

Aldehyde → alcohol conditions

heat

Ketone → alcohol reaction

reduction

Ketone → alcohol reagents

NaBH₄

Ketone → alcohol conditions

Heat

Carboxylic acid → alcohol reaction

reduction

Carboxylic acid → alcohol reagents

LiAlH₄ in dry ether

Carboxylic acid → acid anhydride mechanism

elimination

Carboxylic acid → acid anhydride reagents

P₂O₅

Carboxylic acid → acid anhydride conditions

distillation

Acid anhydride → carboxylic acid mechanism

Nucleophilic addition elimination

Acid anhydride → carboxylic acid reagents

Water

Acid anhydride → carboxylic acid conditions

room temperature

Acid anhydride → ester mechanism

Nucleophilic addition elimination

Acid anhydride → ester reagents

alcohol

Acid anhydride → ester conditions

room temperature

Acid anhydride → 1^o amide mechanism

Nucleophilic addition elimination

Acid anhydride → 1^o amide reagents

Ammonia

Acid anhydride → 1^o amide conditions

room temperature

Acid anhydride → 2^o amide mechanism

Nucleophilic addition elimination

Acid anhydride → 2^o amide reagents

1^o amine

Acid anhydride → 2^o amide conditions

room temperature

Ester → carboxylic acid reaction

hydrolysis

Ester → carboxylic acid reagents

water, concentrated sulphuric acid

Acyl chloride → ester mechanism

Nucleophilic addition elimination

Acyl chloride → ester reagents

alcohol

Acyl chloride → carboxylic acid mechanism

Nucleophilic addition elimination

Acyl chloride → carboxylic acid reagents

water

Acyl chloride → 1^o amide mechanism

Nucleophilic addition elimination

Acyl chloride → 1^o amide reagents

1^o amine

1^o amide → 1^o amine reaction

reduction

1^o amide → 1^o amine reagents

LiAlH₄ in dry ether

1^o amide → nitrile mechanism

elimination

1^o amide → carboxylic acid reaction

hydrolysis

1^o amide → carboxylic acid reagents

H⁺, water

1^o amide → carboxylic acid conditions

reflux

1^o amine → 2^o amide mechanism

nucleophilic addition elimination

1^o amine → 2^o amide reagents

acyl chloride

1^o amine → 2/3^o amine/quaternary ammonia salt mechanism

Nucleophilic substitution

Nitrile → 1^o amine reaction

reduction

Nitrile → 1^o amine reagents

LiAlH₄ in dry ether

Nitrile → carboxylic acid reaction

hydrolysis

Nitrile → carboxylic acid reagents

H+, water

Nitrile → carboxylic acid conditions

reflux

Nitrile → 1^o amide reaction

hydrolysis

Nitrile → 1^o amide reagents

water, acid/base catalyst

Benzene → nitrobenzene mechanism

Electrophilic substitution

Benzene → nitrobenzene reagents

Concentrated nitric acid, concentrated sulphuric acid

Benzene → nitrobenzene conditions

reflux at 55C

Equation for formation of electrophile for nitration of benzene

2H₂SO₄ + HNO₃ <> 2HSO₄^- + H₃O⁺ + NO₂⁺

Uses for nitrobenzene

Used for the formation of dyes and explosives

Benzene → phenylketone/aldehyde mechanism

Electrophilic substitution

Benzene → phenylketone/aldehyde reagents

anhydrous aluminium chloride, acyl chloride

Benzene → phenylketone/aldehyde conditions

Reflux at 50C, dry in inert solvent (ether)

Equation for formation of electrophile for acylation of benzene

AlCl₃ + CH₃COCl → CH₃CO⁺ + AlCl₄^-

Equation of reforming sulphuric acid after nitration of benzene

H⁺ + HSO₄^- → H₂SO₄