Nickel and Palladium Complexes with New Phosphinito-Imine Ligands and Their Application as Ethylene Oligomerization Catalysts
作者:Laura Ortiz de la Tabla、Inmaculada Matas、Pilar Palma、Eleuterio Álvarez、Juan Cámpora
DOI:10.1021/om201088y
日期:2012.2.13
stable phosphinito-imine complexes MX2(P-N) (M = Ni, Pd) in excellent yields. These complexes are diamagnetic and exhibit square-planar structures in the solid state, but in solution, the Ni derivatives exchange with a small amount of the corresponding high-spin tetrahedral isomers. On treatment with MMAO or DEAC, NiX2(P-N) complexes become active ethylene oligomerization catalysts, affording mainly
庞大的芳基酰胺阴离子[R 2 CONAr] -(R 2 = Me或t -Bu; Ar = 2,6- i -Pr 2 C 6 H 4)与氯膦ClP(R 1)2。在溶液中,游离的膦亚基亚胺与相应的酰胺基膦互变异构体平衡存在,后者含有一个与氮结合的P(R 1)2基团。但是,使互变异构体混合物与金属前体配合物(例如NiBr 2(dme)或PdCl 2)反应(鳕鱼),以优异的收率选择性地提供稳定的膦亚胺-亚胺络合物MX 2(PN)(M = Ni,Pd)。这些络合物是反磁性的,并在固态下显示出正方形平面结构,但是在溶液中,Ni衍生物与少量的相应的高自旋四面体异构体进行交换。在用MMAO或DEAC处理后,NiX 2(PN)络合物成为活性的乙烯低聚催化剂,主要提供丁烯以及少量的己烯和辛烯。这些催化剂的活性和选择性取决于膦酰亚胺-亚胺配体和所用助催化剂的结构。当用DEAC活化时,包含P(i -Pr)2部分的复合物极具活性,TOF超过106