Which of the following bicyclic ring systems can be prepared by an intermolecular Robinson annulation?

Question

Quizplus · Accepted Answer

Intermolecular Robinson annulation involves the reaction of an α,β-unsaturated ketone with a cyclic ketone. The product will have a bicyclic structure with a six-membered ring fused to a five-membered ring. Only option III has a five-membered cyclic ketone that can undergo intermolecular Robinson annulation. The other options either lack a cyclic ketone or have a cyclic ketone that cannot undergo this reaction.

Which of the Following Bicyclic Ring Systems Can Be Prepared