Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Haloalkanes and Haloarenes

Question:

Dichlorocarbene is obtained by the \(\alpha\)-elimination of

Options:

CHCl3

CH2Cl2

CH3Cl

All of these

Correct Answer:

CHCl3

Explanation:

The correct answer is option 1. CHCl3

\(\alpha\)-elimination (eliminations in which both the proton and the leaving group are located on the same atom) follow a mechanism akin to an \(E_{1_{cB}}\) β-elimination. A strong base removes an acidic proton adjacent to an electron-withdrawing group to give a carbanion. Loss of a leaving group from the carbanion creates a carbene. One of the best-known elimination reactions occurs when chloroform is treated with base, forming a dichlorocarbene.