Identify the major product formed in the following reaction.

Step-by-step solution

The reaction involves a semi-pinacol rearrangement triggered by electrophilic addition. 1. Electrophilic Attack: The starting material contains an electron-rich enol ether double bond in the dihydrofuran ring. N-Bromosuccinimide (NBS) provides an electrophilic bromine source ( Br^+ ). The Br^+ attacks the -carbon (C3) of the enol ether to form a stable oxonium ion intermediate at the -carbon (C2). 2. Intermediate Formation: The intermediate formed has a positive charge at the C2 position, which is stabilized by res