characterized by NMR spectroscopy and X-ray crystallography. Cyclic voltammetry measurements of the Ni−Br precursors of 2, 3, and 6 indicated that substituting the CH2 moiety in the ligand skeleton by O, or some of the aromatic protons by Cl, renders the metal center less susceptible to oxidation. Evaluating the catalytic activities of 1−3, 6, and the t-Bu analogue of 1 for addition of aniline to acrylonitrile
阳离子钳型配合物[(i -Pr 2 PCH 2 CH 2)2 CH} Ni(NCCH 3)] [BPh 4 ](1),[2,6-(i -Pr 2 PCH 2)2 -C 6 H 3 } Ni(NCCH 3)] [BPh 4 ](2),[2,6-(i -Pr 2 PO)2 -C 6 H 3 } Ni(NCCH 3)] [BPh 4 ] (3)和[2,6-(i已经制备了-Pr 2 PO)2 -3,5-Cl 2 -C 6 H} Ni(NCCH 3)] [BPh 4 ](6),并通过NMR光谱和X射线晶体学对其进行了充分表征。的
镍-
溴前体的循环伏安法的测量2,3,和6表示取代CH 2被O在
配体骨架部分,或一些经Cl的芳族质子的,使得该
金属中心不易被氧化。评估的催化活性1 - 3,6,和吨的-Bu类似物1将
苯胺加到
丙烯腈中的结果表明3是最有效的催化剂前体。的分离[(吨-Bu 2 PCH 2 CH