Question

Ethyldimethylamine is obtained from the reduction of _______ with LiAlH4.

(a) acetamide

(b) benzamide

(c) N-methylacetamide

(d) N,N-dimethylacetamide

The question was posed to me at a job interview.

This interesting question is from Preparation of Amines topic in portion Amines of Chemistry – Class 12

Answer 1

The correct answer is:

(d) N,N-dimethylacetamide

Ethyldimethylamine is obtained by the reduction of N,N-dimethylacetamide with LiAlH₄ (lithium aluminum hydride). LiAlH₄ is a strong reducing agent that can reduce amides to amines. In this case, N,N-dimethylacetamide undergoes reduction to form ethyldimethylamine.

The reduction of other amides (like acetamide or N-methylacetamide) typically results in different amine products.