Total synthesis of pareitropone via radical anion coupling.

A concise (9-step) synthesis of the tropoloisoquinoline alkaloid pareitropone has been achieved starting from 2-bromoisovanillin. The key step features oxidative cyclization of a readily available phenolic nitronate for the convenient construction of the fused tropone ring. This work underscores the synthetic utility of intramolecular oxidative coupling reactions of phenolic nitronates.