ON THE REDUCTION BEHAVIOR OF 2-METHOXYETHYL AND 2-METHYLTHIOETHYL SUBSTITUTED ZIRCONOCENE DICHLORIDES - CRYSTAL-STRUCTURE OF (ETA(5),SIGMA-C5ME4CH2CH2S)(2)ZR

A reduction of previously reported 2-methoxyethyl and 2-methylthioethy l functionalized zirconocenedichlorides (eta(5)-C5Me4CH2CH4EMe) (eta(5 )-C5Me5)ZrCl2 (E = O, S) and (eta(5)-C5Me4CH2CH2E'Me) (eta(5)-C5Me4CH2 CH2E'Me)ZrCl2 (E= O, S; E' = O, S) with Mg/Hg in THF leads unexpectedl y to the products of O-Me and S-Me bond cleavage (eta(5),sigma-C5Me4CH 2CH2E)(eta(5)-C5Me5)ZrMe (E = O, S), (eta(5),sigma-C5Me4CH2CH2E) (eta( 5)-C5Me4CH2CH2E'Me) ZrMe (E = O, S; E' = 0), and (eta(5),sigma-C5Me4CH 2CH2S)(2)Zr respectively. The crystal structure of (eta(5), sigma-C5Me 4CH2CH2S)(2)Zr was established by X-ray analysis. At the same time the reduction of (eta(5)-C5Me4CH2CH2EMe) (eta(5)-C5Me5)ZrCl2 (E = O, S) u nder 1 atm of CO gives either only the usual dicarbonyl derivative (et a(5)-C5Me4CH2CH2EMe) (eta(5)-C5Me5)Zr(CO)(2) (E = O) or a complex mixt ure of products (E = S). (C) 1998 Elsevier Science S.A. All rights res erved.