Question

Dehydration of alcohols take place more rapidly with $POC{l}_3$ than with $H_{2}S{O}_4.$

Select the correct statements(s) about the above dehydration reaction :

• A. It does not involve carbocation.
• B. It involves $R-OPOC{l}_2$ with $-OPOC{l}_2$ as a better leaving group.
• C. It involves $E2$ mechanism as pyridine base abstracts proton from the adjacent carbon as the same time at which $-OPOC{l}_2$ is leaving.
• D. It is $E1$ reaction without formation of carbocation.

Answer 1

Answer: (A), (B), (C)

It involves $R-OPOC{l}_2$ with $-OPOC{l}_2$ as a better leaving group.
It involves $E2$ mechanism as pyridine base abstracts proton from the adjacent carbon as the same time at which $-OPOC{l}_2$ is leaving.
It does not involve carbocation.

1. Nucleophilic attack and deprotonation.

2. $E-2\beta -$ Hydrogen elimination.

Hence the correct options are A, B and C.