Selective C-H Functionalization Reaction
Palladium catalyzed coupling between aryl halides and alkenes (Mizoroki-Heck reaction) is one of the most popular reactions for synthesizing complex organic molecules. The limited availability, problematic synthesis, and higher cost of aryl halide precursors (or their equivalents) have encouraged exploration of direct olefination of aryl carbon-hydrogen (C–H) bonds (Fujiwara-Moritani reaction). Despite significant progress, the restricted substrate scope, in particular noncompliance of unactivated aliphatic olefins, has discouraged the use of this greener alternative. Overcoming this serious limitation, a palladium-catalyzed chelation-assisted ortho-C–H bond olefination of phenyl acetic acid derivatives with unactivated, aliphatic alkenes in good to excellent yields with high regio- and stereoselectivities has been reported. The versatility of this operationally simple method has been demonstrated through drug diversification and for synthesizing divinyl benzene derivatives.