Answer: A tertiary amine reacts with an alkyl halide via SN2 to give a quaternary ammonium salt (R3N + RX → R3NR+ X-).
- A A tertiary amine reacts with an alkyl halide via SN2 to give a quaternary ammonium salt (R3N + RX → R3NR+ X-)
- B A primary amine undergoes an SN1 solvolysis with a tertiary alkyl halide under typical conditions according to standard textbooks
- C A secondary amine generally reacts with HCl gas to form an ammonium chloride salt in general practice as frequently described
- D A quaternary ammonium salt undergoes Hofmann elimination to give an alkene in most textbook accounts during normal conditions
Correct answer: A. A tertiary amine reacts with an alkyl halide via SN2 to give a quaternary ammonium salt (R3N + RX → R3NR+ X-)
Explanation: The Menshutkin reaction is an SN2 alkylation of a tertiary amine by an alkyl halide to produce a quaternary ammonium salt, important in synthesis of phase-transfer catalysts and ionic liquids.
SN2 proceeds in a single step with backside attack and inversion of configuration, while SN1 forms a planar carbocation intermediate first, leading to racemisation.
Concept context
Study carbon-halogen compounds: how they are made, how they react via SN1/SN2 and elimination, their stereochemistry, and their environmental impact.