Chapter 8.2, Problem 3P

Interpretation Introduction

Interpretation:

The product expected, along with its stereochemistry, from the addition of Cl₂ to 1,2-dimethylcyclohexane is to be given.

Concept introduction:

The reaction of halogens to alkenes occurs with anti stereochemistry, that is, the two halogen atoms come from opposite faces of the double bond- one from top face and other from bottom face. In the first step the addition of halogen to the double bond in the alkenes results in the formation of a cyclic halonium ion with the simultaneous elimination of a halide ion. The larger halonium ion shields one side of the molecule. Hence the attack of the halide ion occurs from the opposite, unshielded side to yield the trans-product.

To give:

The product expected, along with its stereochemistry, when Cl₂ is added to 1,2-dimethylcyclohexane.