Two equivalents of benzaldehyde react with the ketone shown in aqueous ethanolic NaOH at room temperature until both alpha carbons have condensed (all water lost). Which structure is the product?

AStructure A
BStructure B
CStructure C
DStructure D

Answer: C

The drawn compound is cyclohexanone. Twofold Claisen-Schmidt condensation at both alpha carbons gives (2E,6E)-2,6-dibenzylidenecyclohexanone (E checked by RDKit CIP). Structure A has only one condensation, B is the undehydrated double aldol, and D would need reduction of the C=C.

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Two equivalents of benzaldehyde react with the ketone shown in aqueous ethanolic NaOH at room temperature until both alpha carbons have condensed (all water lost). Which structure is the product?

Answer: C

More questions on Aldol and intramolecular aldol products of drawn carbonyls