Pincer 型カルベンリガンドを用いるニッケル触媒反応の開発

抄録

N-Heterocyclic carbenes (NHCs) have attracted an attention as alternatives to phosphine ligands in transition metal-catalyzed reactions and highly active catalyst systems have been realized utilizing them. Recently, we reported that a novel NHC-derived pincer-type nickel(II) complex 1, readily prepared and air- and moisture-stable, could efficiently catalyze the Heck reaction. In order to examine the reactivity of nickel complex 1 in detail, we also investigated the Suzuki and Kumada coupling reactions. As a result, various aryl bromides, chlorides, and fluorides reacted smoothly with phenylboronic acid or Grignard reagents and the coupled products were obtained in high yields. Further studies, involving the expansion of the scope of substrates and the applications of nickel complex 1 toward various coupling reactions, are underway.

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