AQA A Level Chemistry Mechanisms

• Nucleophilic substitution via NH3 (mechanism)


  Excess, concentrated ammonia in a sealed container under pressure

  
• Nucleophilic substitution via CN- (mechanism)


  Ethanolic KCN, heat under reflux

  
• Nucleophilic substitution via OH- (mechanism)

  Aqueous NaOH, heat under reflux

  
• Elimination via OH- (mechanism)


  Requires hot, ethanolic KOH

  
• Electrophilic addition via HBr (mechanism)

  
• Electrophilic addition via H2SO4 (mechanism)


  Concentrated H2SO4

  
• Electrophilic addition via Br2 (mechanism)

  
• Elimination of (water from) alcohols (mechanism)


  Concentrated-acid catalysed (where H+ comes from)

  
• Hydration of ethene (mechanism)


  Acid catalyst, 60 atm, 600K

  
• Acyl chloride with water (Nucleophilic addition-elimination) (mechanism)

  
• Acyl chloride with alcohol (Nucleophilic addition-elimination) (mechanism)

  
• Acyl chloride with ammonia (Nucleophilic addition-elimination) (mechanism)

  
• Acyl chloride with primary amine (Nucleophilic addition-elimination) (mechanism)

  
• Acid anhydride with water (Nucleophilic addition-elimination) (mechanism)

  
• Acid anhydride with alcohol (Nucleophilic addition-elimination) (mechanism)

  
• Acid anhydride with ammonia (Nucleophilic addition-elimination) (mechanism)

  
• Acid anhydride with primary amine (Nucleophilic addition-elimination) (mechanism)

  
• Electrophilic substitution via NO2 (nitration) (mechanism)


  H2SO4 catalyst

  
• Electrophilic substitution by acyl chloride/acid anhydride (mechanism)


  AlCl3 catalyst

  
• Nucleophilic addition by NaBH4 (mechanism)

  
• Nucleophilic addition by CN- (mechanism)

  
• alkane → halogenoalkane

  reagent:

  condition:

  type of reaction:

  reagent: X2

  condition: uv light

  type of reaction: free radical substitution
• alkene → halogenoalkane

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: HX

  condition:

  type of reaction: electrophilic addition

  
• alkene → dihalogenoalkane

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: X2

  condition:

  type of reaction: electrophilic addition

  
• alkene → alcohol

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: H2O

  condition: conc H2SO4/H3PO4, 600K, 60atm

  type of reaction: electrophilic addition

  
• primary halogenoalkane → primary amine

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: conc NH3

  condition: sealed container under pressure

  type of reaction: nucleophilic substitution

  
• primary halogenoalkane → secondary amine

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: primary amine

  condition: ethanolic amine

  type of reaction: nucleophilic substitution

  
• halogenoalkane → alcohol

  (draw mechanism for 1°, 2°, 3° alc)

  reagent:

  condition:

  type of reaction:

  reagent: aqueous NaOH

  condition: heat under reflux

  type of reaction: nucleophilic substitution

  
• halogenoalkane → alkene

  reagent:

  condition:

  type of reaction:

  reagent: ethanolic KOH

  condition: heat under reflux

  type of reaction: elimination
• halogenoalkane → nitrile

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: ethanolic KCN

  condition:

  type of reaction: nucleophilic substitution

  
• alcohol → alkene

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: conc H2SO4/H3PO4

  condition: 170°

  type of reaction: elimination

  
• alchohol → halogenoalkane

  reagent:

  condition:

  type of reaction:

  reagent: HX prepared in-situ with NaX and conc H2SO4

  condition: heat under reflux

  type of reaction: substitution
• primary alcohol → aldehyde

  reagent:

  condition:

  type of reaction:

  reagent: acidified K2Cr2O7 (oxidising agent)

  condition: heat and distill

  type of reaction: oxidation
• secondary alcohol → ketone

  reagent:

  condition:

  type of reaction:

  reagent: acidified K2Cr2O7 (oxidising agent)

  condition: heat under reflux

  type of reaction: oxidation
• aldehyde → carboxylic acid

  reagent:

  condition:

  type of reaction:

  reagent: acidified K2Cr2O7

  condition: heat under reflux

  type of reaction: oxidation
• aldehyde → alcohol

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: NaBH4

  condition: aqueous solution

  type of reaction: nucleophilic addition

  
• ketone → alcohol

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: NaBH4

  condition: aqueous solution

  type of reaction: nucleophilic addition

  
• aldehyde/ketone → hydroxynitrile

  (draw mechanism)

  reagent:

  condition:

  type of reaction:

  reagent: KCN followed by dilute acid

  condition: aqueous solution

  type of reaction: nucleophilic addition

  
• carboxylic acid → aldehyde

  reagent:

  condition:

  type of reaction:

  reagent: LiAlH4

  condition: in dry ether

  type of reaction: reduction
• carboxylic acid → alcohol

  reagent:

  condition:

  type of reaction:

  reagent: LiAlH4

  condition: in dry ether

  type of reaction: nucleophilic addition