文摘
Although there are many organic reactions that are catalyzed by either Ni0 or Pd0 complexes, in comparison with the case for Pd0 there has been significantly less work studying coordinatively unsaturated Ni0 complexes. Here, we develop a simple synthetic route for preparing a number of thermally stable NHC-supported Ni0 hexadiene complexes in good yield. We examine the stoichiometric reactivity of one of these species and demonstrate that the coordinated hexadiene moiety is labile and can be replaced with a variety of different ligands, including CO, phosphines, isonitriles, and olefins. In addition, we show that the Ni0 hexadiene complexes are relatively rare examples of homogeneous first-row transition-metal catalysts for the hydrogenation of olefins.