Methyl-Substituted Zirconocene−Bis(trimethylsilyl)acetylene Complexes (C<sub>5</sub>H<sub>5</sub><sub>-</sub><i><sub>n</sub></i>Me<i><sub>n</sub></i>)<sub>2</sub>Zr(η<sup>2</sup>-Me<sub>3</sub>SiC⋮CSiMe<sub>3</sub>) (<i>n</i> = 2−5)
作者:Jörg Hiller、Ulf Thewalt、Miroslav Polášek、Lidmila Petrusová、Vojtech Varga、Petr Sedmera、Karel Mach
DOI:10.1021/om960184j
日期:1996.8.20
The (C(5)H(5-n)Me(n))(2)Zr[eta(2)-C-2(SiMe(3))(2)] (n = 2-5; 1,3-dimethyl, 1,2,3-trimethyl) (2C-F) complexes were prepared by the reduction of corresponding zirconocene dichlorides with magnesium in THF in the presence of bis(trimethylsilyl)acetylene (BTMSA). All of them are stable in the absence of THF. Crystal structures of (C(5)HMe(4))(2)Zr[eta(2)-C-2(SiMe(3))(2)] (2E) and (C(5)Me(5))(2)Zr[eta(2)-C-2(SiMe(3))(2)] (2F) and ofthe analogous titanium complexes are isomorphous. The red shift of the nu(C=C) vibration and the downfield shift of C-13 delta(C=C) indicate that BTMSA in 2C-F is more strongly coordinated than in analogous titanocene complexes. The nonisolated complex (C(5)H(4)Me)(2)Zr[eta(2)-C-2(SiMe(3))(2)](THF) (2B . THF) rearranges after the loss of THF to give the dimer [(eta(5)-C(5)H(4)Me)(eta(1)-C(SiMe(3))=CH(SiMe(3))Zr(mu-eta(1):eta(5)-C(5)H(3)Me)](2) (3B).