Hydrogen chloride protonates the benzylic hydroxyl group, and loss of water gives a benzylic carbocation. The adjacent spiro cyclopentane ring relieves strain by a 1,2-bond migration that enlarges it to a six-membered ring, moving the positive charge onto the newly formed ring and building the octahydrophenanthrene framework. Potassium hydroxide then removes a β-hydrogen from this tertiary carbocation, and elimination installs a carbon–carbon double bond in that ring while the aminoethyl group remains on the quaternary carbon. The product B is the tricyclic amine carrying this ring double bond.
JEE Main · 2023 · 13 Apr 2023 · Shift 1 · Single correct option
