Question

The compounds A, B and C react with methyl iodide to give finally quaternary ammonium iodides. Only C gives carbylamine test while only A forms yellow oily compound on reaction with nitrous acid. The compounds A, B and C are respectively. a) Butan — 1 — amine, N — Ethylethanamine and N, N — Dimethylethanamine. b) N—Ethylethanamine, N, N — Dimethyletha - namine and Butan — 1 — amine. c) N, N—Dimethylethanamine, N — Ethylethanamine and Butan —1 — amine. d) N— Ethylethanamine, Butan —1— amine and N— Ethylethanamine.

Answer 1

answer :- option (c)


explanation :- The compounds A, B and C react with methyl iodide to give finally quaternary ammonium iodides. Only C gives carbylamine test while only A forms yellow oily compound on reaction with nitrous acid. The compounds A, B and C are respectively.

we know, dimethylamine reacts with nitrous acid and gives yellow oily compound.
so, compound A should be N,N- dimethylamine.

butan-1- amine gives carbylamine test.
so, compound C should be butan-1-amine.

so, the correct option is option (C)

Answer 2

Explanation:

primary amines react with excess methyl iodide to form quaternary ammonium salts.

The explanation is as follows :

The nitrogen atom of primary amines contains a lone pair of electron. So, primary amines are strongly nucleophilic in nature. Moreover, the hydrogen atoms on nitrogen are easily replaceable. So, primary amines can act as nucleophiles and can react with alkyl halides. In the presence of excess alkyl halides, one amine molecule can repeatedly react with a number of alkyl halide molecules and result in the formation of a quaternary ammonium salt.

The reaction is as follows :

RNH

2

+3CH

3

I→[RN(CH

3

)

3

]

+

(quaternary ammonium salt)

Here, in the options, only option C is a primary amine.

So, C is a correct answer