SYNTHESIS AND X-RAY CRYSTAL-STRUCTURE OF ADIENYL)-1,1,3,3-TETRAMETHYLDISILOXANE]HAFNIUM(IV) DICHLORIDE

The tetramethyldisiloxane-bridged hafnocene complex [HfCl2{mu-(eta(5)- C5H4)SiMe2OSiMe2(eta(2)-C5H4)}] (1) has been prepared by the reaction of HfCl4 with the dilithiated bis(cyclopentadienyl)disiloxane (LiC5H4S iMe2)(2)O in a molar ratio of 1:2. The new compound was characterized by spectroscopic and X-ray diffraction methods. The crystals are monoc linic of space group P2(1)/c and isostructural with the corresponding complexes of titanium and zirconium. The unit cell dimensions are a = 13.51(1)Angstrom, b = 8.672(7)Angstrom, c = 15.41(1) Angstrom, beta = 97.15(2)degrees, and Z = 4.