Emerging Nickel Catalysis in Heck Reactions: Recent Developments

Abstract The synthetic application of nickel catalysts in Heck‐coupling reactions is quite prominent and noticeable of late in organic synthesis. It shows great interest over the other transition metal catalysts due to its unique characteristic that prepares them more significantly applicable in different fields of synthetic application. The usefulness of nickel‐catalysts relies in the fact that they are abundant in nature, relatively less precious and environment friendly. Nickel plays pivotal role in different kind of Heck reactions known such as intramolecular‐, intermolecular‐, reductive‐Heck type reaction producing mainly carbocycles and hetero cycles of biological significance. Carbocyclization or hetero‐cyclization reaction occurred under optimized reaction conditions developed and come up with the formation of various structural building blocks of naturally occurring compounds. Via reductive Heck cyclization large membered ring of carbo‐ or hetero‐cyclic system was formed which performed key role as building blocks in pharmaceutical synthesis and bioactive molecule formation. Intermolecular Heck type reactions were comparatively more explored. Silyl‐Heck, carbonyl‐Heck, and other miscellaneous type reactions were covered up through nickel‐catalyzed intermolecular Heck reaction. Asymmetric versions of Heck‐ coupling reactions are also reported to proceed even with unactivated alkenes, offering molecules having quaternary stereogenic center in a regio‐ and enantioselective manner. This manuscript intends to cover these entire concepts. magnified image