Studies on a Simple Route to a Bicyclic Reserpine Intermediate

Abstract
A concise route is described to a Reserpine synthetic intermediate having the features of ring E and an oxygen function for constructing ring D. This involves an unusual α-diketone cleavage, the selective elaboration of the carboxylated ring in 1-naphthoic acids and selective boron halide cleavage of ester and ether groups.