High Quality Content by WIKIPEDIA articles! The Heck reaction (also called the Mizoroki-Heck reaction) is the chemical reaction of an unsaturated halide (or triflate) with an alkene and a strong base and palladium catalyst to form a substituted alkene. Together with the other palladium-catalyzed cross coupling reactions, this reaction is of great importance, as it allows to do substitution reactions on planar centers. It is named after the American chemist Richard F. Heck.