Decomposition of Methylnickel(II) Amido, Alkoxo, and Alkyl Complexes by β-Hydrogen Elimination: A Comparative Study

Thermal decomposition of structurally related amido, alkoxo, and alkyl complexes of type [Ni(Me)(EC(H)RR′)(dippe)] (EC(H)RR′ = cyclo-NC4H8 (pyrrolidino), N(CH2Ph)2, OCH2Ph, OCH(Me)Ph, and CH2CH2Ph) takes place through formally analogous processes involving β-hydrogen elimination and reductive elimination of methane, cleanly affording corresponding Ni(0) imine, aldehyde, ketone, and olefin complexes, [Ni(η2-ECRR′)(dippe)]. Kinetic studies on these decomposition reactions show that, in spite of their similarity, they involve substantial mechanistic differences.

针对[Ni(Me)(EC(H)RR′)(1,2-双(二异丙基膦)乙烷，dippe)]型结构相关的酰胺基、烷氧基与烷基配合物的热分解反应：其中EC(H)RR′分别为吡咯烷基（pyrrolidino，cyclo-NC4H8）、二苄基氨基（N(CH2Ph)2）、苄氧基（OCH2Ph）、1-苯基乙氧基（OCH(Me)Ph）以及苯乙基（CH2CH2Ph）。该类反应虽均通过形式上类似的β-氢消除与甲烷还原消除过程进行，却可无明显副产物地生成对应的零价镍亚胺、醛、酮与烯烃配合物[Ni(η2-ECRR′)(dippe)]。对该类分解反应的动力学研究表明，尽管反应表观相似，其内在机理却存在显著差异。