Identify the major product of the following reaction:

Step-by-step solution

The reaction proceeds via a tandem oxa-Michael addition followed by an intramolecular aldol condensation. 1. Oxa-Michael Addition: In the presence of a base ( OH^- ), the phenolic -OH group of salicylaldehyde is deprotonated to form a phenoxide ion. This nucleophilic phenoxide ion attacks the -carbon of the , -unsaturated ketone (methyl vinyl ketone) in a conjugate addition manner. This forms the intermediate 2-(3-oxobutoxy)benzaldehyde. 2. Intramolecular Aldol Condensation: The intermediate contains both an aldehy