Abstract:

The Heck reaction is a widely used carbon-carbon bond forming process in organic synthesis. An important variant of this reaction developed by Matsuda in 1977 introduced arenediazonium salt as arylating agent. It has emerged as a greener, faster and more practical alternative to the conventional Heck protocols. In 2007, we presented the application of an efficient regio- and stereoselective Heck-Matsuda (HM) arylation of N-carbomethoxy-L-3-dehydroproline methyl ester (1) with arenediazonium tetrafluoroborates in the syntheses of aryl kainoids with potent neurotoxic activities. Recently, new studies using arenediazonium salts containing EWG showed an unexpected inversion of the enantioselectivity in these substrate directable HM reactions. Herein we report the details of these investigations and a possible rationalization for this surprising result.