Nickel-Catalyzed Heck Reaction

[摘要] The Heck reaction is a chemical reaction for creating C–Cbonds between alkenes and aryl halides in the presence of asuitable catalyst.1 It is widely used in various conversions,synthesis of intermediates, natural products, and biologically active compounds. Traditionally, a suitable catalyst inthe presence of base is required for Heck1 coupling reactionas shown in Scheme 1. The steps2 involved in the plausiblemechanism initiates with the activation of catalyst. Theelectrophilic moiety undergoes oxidative addition to produce an intermediate, which further go through olefin addition. This step is followed by migratory insertion, -hydrideelimination, and regeneration of the catalyst.3 Apart fromthe decisive use of palladium catalysts for this reaction,propitious results are also being revealed by researchers forthe newly customized nickel-based catalysts from last fewyears.4 Switching the metal from Pd to Ni has shown improved and distinctive selectivity in certain cases. Thisowes to the unique behavior of nickel as a transition metalto entwine with other systems.5 Nickel metal salts, its complexes6 along with Ni bimetallic systems,7 alloys, and Ninanoparticles8 lead to extensive catalytic applicability.Nickel catalysts along with phosphine-based ligands werealso extensively used by researchers for Heck reaction.

[学科分类] 精神健康和精神病学

[关键词] alkenes;aryl halides;coupling;Heck reaction;nickel