Abstrakt
Complex [Zr{eta(5)-C5Me4(SiMe2H)}(2)Cl-2] (1) was prepared by the reaction of lithium salt of 2,3,4,5-tetramethyl-1-(dimethylsilyl) cyclopenta-2,4-diene with [ZrCl4] in boiling THF. The reduction of 1 with excess magnesium in THF in the presence of excess bis(trimethylsilyl)-acetylene (btmsa) afforded the bivalent metal ansa-disilylene complex with pi-coordinated btmsa [Zr(eta(2)-btmsa){eta(5)-C5Me4(SiMe2)}(2)] (2).
The dehydrocoupling of SiMe2H groups was accompanied by a hydrogen transfer to releasing btmsa to give a mixture of cis- and trans-1,2- bis(trimethylsilyl) ethene. Chlorination of 2 with PbCl2 afforded ansa-[Zr{eta(5)-C5Me4(SiMe2)}(2)Cl-2] (3) and liberated btmsa.
The crystal structures of complexes, 1, 2 and 3 have been determined by X-ray crystallography.