Practical First Total Synthesis of the Potent Phytotoxic (±)-Naphthotectone, Isolated from Tectona grandis

Abstract

Naphthotectone is a quinone isolated recently from teak extracts of Tectona grandis. It has been shown to be one of the most abundant compounds and the most active compound isolated form teak. Thus, it has been proposed that naphthotectone is one of the compounds responsible for the allelophathic activity of this plant. An efficient total synthesis of (±) -naphthotectone was achieved in seven steps and 31% overall yield. The best results were obtained by using an aqueous Wittig reaction as a key step. Other reactions used were the formation of an epoxide ring by the Corey– Chaykovsky method, and an innovative one-pot anodic electrooxidation and demethylation.