Cyanation
Cyanide substitution forms a nitrile and extends the carbon chain by one carbon.
- Reagents
- KCN or NaCN
- Conditions
- ethanol, reflux
- Reaction class
- nucleophilic substitution
- Equation
- R-I + CN- -> R-CN + I-
Overview
Cyanide substitution forms a nitrile and extends the carbon chain by one carbon.
Transformation
- Equation
- R-I + CN- -> R-CN + I-
- Reagents
- KCN or NaCN
- Environment
- ethanol, reflux
- Reaction class
- nucleophilic substitution
- Mechanism
- nucleophilic substitution
- Evidence level
- textbook core
Scope and limitations
- Scope
- Cyanide substitution of iodoalkanes; the carbon chain increases by one carbon.
- Limitations
- Cyanide reagents are hazardous; carbon attack gives nitriles under the scoped conditions. Other cyanide sources can favour different products and belong to separate routes.
Related reactions
- Iodination: Alcohols → Iodoalkanes
Iodine and red phosphorus conditions convert alcohols into iodoalkanes.
- Hydroiodination: Alkenes → Iodoalkanes
Addition of hydrogen iodide across an alkene can form an iodoalkane.
- Cyanation: Chloroalkanes → Nitriles
Cyanide substitution forms a nitrile and extends the carbon chain by one carbon.
- Cyanation: Bromoalkanes → Nitriles
Cyanide substitution forms a nitrile and extends the carbon chain by one carbon.
- Amination: Iodoalkanes → Amines
Ammonia substitutes iodide to form a primary amine; excess ammonia limits further alkylation.
- Hydrolysis: Iodoalkanes → Alcohols
The C-I bond can be displaced by hydroxide to form an alcohol.
- Elimination: Iodoalkanes → Alkenes
Base-promoted elimination removes HI to form an alkene.
- Hydrolysis: Nitriles → Carboxylic acids
Nitriles can be hydrolysed to carboxylic acids, splitting the old aggregate nitrile-to-amide route into a single functional-group conversion.
- Reduction: Nitriles → Amines
Nitriles can be reduced to primary amines, separating the amine feedstock route from later amide or materials chemistry.
- Grignard formation: Iodoalkanes → Grignard reagents
Iodoalkanes can react with magnesium in dry ether to form Grignard reagents.
References
- Pearson Edexcel Level 3 Advanced GCE in Chemistry specificationPearson Education Limited · Pearson qualifications · 2024
Supports the textbook-core organic reaction routes used for displayed route and mechanism content.