Alkylation
Amines can be further alkylated to permanent cationic quaternary ammonium groups used in antimicrobial and ion-exchange materials.
- Reagents
- alkyl chloride or related alkylating agent
- Conditions
- solvent and substrate dependent
- Reaction class
- nucleophilic substitution / salt formation
- Equation
- R3N + R-Cl -> R4N+ Cl-
Overview
Amines can be further alkylated to permanent cationic quaternary ammonium groups used in antimicrobial and ion-exchange materials.
Transformation
Amines → Quaternary ammonium compounds
- Equation
- R3N + R-Cl -> R4N+ Cl-
- Reagents
- alkyl chloride or related alkylating agent
- Environment
- solvent and substrate dependent
- Reaction class
- nucleophilic substitution / salt formation
- Mechanism
- alkylation
- Evidence level
- application bridge
Scope and limitations
- Scope
- Tertiary amines undergo alkylation with an alkyl halide to form quaternary ammonium salts.
- Limitations
- The displayed equation is specifically the final alkylation of a tertiary amine, R3N. Primary and secondary amines require further alkylation steps and can give mixtures.
Related reactions
- Amination: Chloroalkanes → Amines
Ammonia substitutes chloride to form a primary amine; excess ammonia limits further alkylation.
- Amination: Bromoalkanes → Amines
Ammonia substitutes bromide to form a primary amine; excess ammonia limits further alkylation.
- Amination: Iodoalkanes → Amines
Ammonia substitutes iodide to form a primary amine; excess ammonia limits further alkylation.
- Surface immobilization: Quaternary ammonium compounds → Antibacterial coatings
Immobilized quaternary ammonium groups are studied for contact-active antibacterial coatings.
- Reduction: Nitriles → Amines
Nitriles can be reduced to primary amines, separating the amine feedstock route from later amide or materials chemistry.
- Acylation co reactant: Amines → N-substituted amides
Amines are acylated by acyl chlorides to form N-substituted amides.
- Charged polymer network: Quaternary ammonium compounds → Ion-exchange materials
Quaternary ammonium groups can form fixed cationic sites in ion-exchange resins and membranes.
- Weak base equilibrium: Amines → Aqueous alkylammonium ions
Amines are weak bases in water and form alkylammonium and hydroxide ions.
- Salt formation: Amines → Amine salts
Amines react with acids to form alkylammonium salts.
- Copper(II) complex formation: Amines → Copper-amine complexes
Amines react with aqueous copper(II) ions and form a deep-blue complex in excess amine.
References
- Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium SaltsYan Xue; Huining Xiao; Yi Zhang · International Journal of Molecular Sciences · 2015
Review-level support for quaternary ammonium antimicrobial polymer concepts.