Question

Propose a mechanism for the following reaction:

Short answer

Start by counting the atoms in the reactant and product while making a cyclic molecule. This allows you to view the atoms in the cyclic product that become connected to one another.

Step-by-step solution

Step 1

Start by counting the atoms in the reactant and product while making a cyclic molecule. This allows you to view the atoms in the cyclic product that become connected to one another.

Step 2:

• Addition of chlorine to alkene, it forms chloronium ion intermediate, the chloronium ion intermediate reacts with a nucleophile.
• There are two nucleophiles in the solution that can react with the intermediate, a Cl and the OH group at the end of molecule.
• There is a greater probability that the OH group will be the nucleophile that attacks the chloronium ion because, since it is attached to the reactant, it does not have to wander through the solution to find the chloronium ion as the Cl has to.
• Loss of a proton gives the six-membered ring ether.