Chapter 8.SE, Problem 49AP

Interpretation Introduction

Interpretation:

Addition of HCl to 1-methoxycyclohexane yields 1-chloro-1-methoxycyclohexane as a sole product. Why the formation of the other alternate regioisomer is not possible in the reaction is to be explained using the resonance structures of the carbocation intermediate formed.

Concept introduction:

The addition of hydrogen halides to alkenes takes place through the formation of a stable carbocation intermediate by the attack of the π electrons in the double bond on the positively polarized hydrogen of the hydrogen halide. The halogen is eliminated as a halide ion. In the second step, the halide ion reacts with the carbocation to yield the product. A carbonium ion stabilized by resonance is more easily formed.

To explain:

Using the resonance structures of the carbocation intermediate formed why addition HCl to 1-methoxycyclohexane yields 1-chloro-1-methoxycyclohexane as a sole product and other alternate regioisomer is not formed.