Synthesis of benzyl substituted naphthalenes from benzylidene tetralones

Tetrahedron Lett. 2012 Jan 25;53(4):373-376. doi: 10.1016/j.tetlet.2011.11.065.

Abstract

A convenient and efficient synthesis of novel highly substituted dimethoxybenzylnaphthalenes, which are precursors to several dihydroxynaphthoic acids, is described. The approach involves the use of aldol chemistry to provide a number of benzylidene tetralones, which are converted to the target naphthalenes in three steps, with good to excellent yields. Grignard reaction of intermediate benzyl tetralones provided 1-substituted benzyl naphthalenes. The reported synthesis is flexible and scalable and provides access to naphthalenes having a variety of substitution patterns. These benzyl substituted naphthalenes are being converted to naphthoic acids and the bioactivities of these compounds are currently being investigated.

Keywords: Benzylidene tetralone; Benzylnaphthalene; Benzyltetralone.