Department of Chemistry and Center for Nanoscience & Nanotechnology, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan.
Dalton Trans. 2012 Jan 28;41(4):1381-8. doi: 10.1039/c1dt11338k. Epub 2011 Nov 29.
A series of organonickel(II) complexes incorporating an amido phosphine ligand tethered with an amino pendant have been prepared and characterized. Deprotonation of N-(dimethylaminoethyl)-2-diphenylphosphinoaniline (H[PNN]) with one equivalent of n-BuLi in ethereal or hydrocarbon solutions at -35 °C generates cleanly dimeric {Li[PNN]}(2) as yellow crystals. The reaction of NiCl(2)(DME) with {Li[PNN]}(2) in THF at -35 °C affords green crystalline [PNN]NiCl. Treating [PNN]NiCl with NaX in acetone solutions gives [PNN]NiX (X = Br, I). Alkylation or arylation of [PNN]NiCl with appropriate Grignard reagents in THF at -35 °C produces red crystalline [PNN]NiR (R = Me, Et, i-Bu, n-hexyl, CH(2)Ph, Ph). The chloride complex [PNN]NiCl was found to be an active catalyst precursor for Kumada coupling reactions of PhX (X = I, Br, Cl) with aryl or alkyl Grignard reagents, including those containing β-hydrogen atoms. The X-ray structures of {Li[PNN]}(2) and [PNN]NiX (X = Cl, Br, Me, Et, n-hexyl) are reported.
一系列含有酰胺膦配体并带有氨基侧链的有机镍（II）配合物已经被制备和表征。N-(二甲氨基乙基)-2-二苯基膦苯胺（H[PNN]）在乙醚或烃溶液中用 1 当量的正丁基锂于-35°C 下脱质子，生成纯净的二聚体{Li[PNN]}(2)，为黄色晶体。NiCl(2)(DME)与{Li[PNN]}(2)在 THF 中于-35°C 反应得到绿色结晶[PNN]NiCl。[PNN]NiCl 与 NaX 在丙酮溶液中反应得到[PNN]NiX（X = Br，I）。[PNN]NiCl 与适当的格氏试剂在 THF 中于-35°C 下进行烷基化或芳基化反应，生成红色结晶[PNN]NiR（R = Me，Et，i-Bu，n-hexyl，CH(2)Ph，Ph）。发现氯化物配合物[PNN]NiCl 是 Kumada 偶联反应的有效催化剂前体，可用于 PhX（X = I，Br，Cl）与芳基或烷基格氏试剂的偶联反应，包括含有β-氢原子的格氏试剂。报道了{Li[PNN]}(2)和[PNN]NiX（X = Cl，Br，Me，Et，n-hexyl）的 X 射线结构。
