Synthesis and Crystal Structure of a Novel η~3-benzyl Cyclopentadienyl Nickel Complex

A novel η3-benzyl cyclopentadienyl nickel complex,(η5-cyclopentadienyl)[7-phenyl-7-(trimethyl)silyl-1,2,7-η3-benzyl]nickel(1),was synthesized by the reaction of nickelocene with 1,1-diphenyl(trimethylsilyl)methyl lithium.The structure was characterized by NMR,MS,elemental analysis and single crystal X-ray diffraction.1 belongs to monoclinic system,space group C1 2/c 1 with a=19.218 0(6),b=16.633 0(5),c=14.388 0(4),α=90.00°,β=123.91°,γ=90.00°,V=3 816.73(20)3,Z=8.The results showed that 1 possessed 18 valence electron configuration which contains η3-benzyl group.Tetraphenyl ethylene and other organonickel clusters were also isolated from the products.Mechanism of the reaction was discussed.Formation of tetraphenyl ethylene in the reaction proved the dissociation of C-Si bond.