Question

Why is Thionyl chloride preferred in the preparation of alkyl halide using alcohol?

Answer 1

Thionyl chloride:

Thionyl chloride$\left({\mathrm{SOCl}}_2\right)$ is used as a Chlorinating agent in organic reactions.

The reason why Thionyl chloride is used in the preparation of alkyl chloride from alcohol:

• In the preparation of alkyl chloride from alcohols. Thionyl chloride is preferred because alkyl halide is prepared using thionyl chloride the by-products that we get are ${\mathrm{SO}}_2\mathrm{and}\mathrm{HCl}.$
• These are both gases and they escape out leaving behind the desired product which is an alkyl chloride.

${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}+{\mathrm{SOCl}}_2\to {\mathrm{C}}_2{\mathrm{H}}_5\mathrm{Cl}+{\mathrm{SO}}_2+\mathrm{HCl}$