On the reduction behaviour of 2-methoxyethyl and 2-methylthioethyl substituted zirconocene dichlorides: crystal structure of (η5,σ-C5Me4CH2CH2S)2Zr

Abstract A reduction of previously reported 2-methoxyethyl and 2-methylthioethyl functionalized zirconocenedichlorides ( η 5 -C 5 Me 4 CH 2 CH 2 EMe)( η 5 -C 5 Me 5 )(ZrCl 2 (E = O, S) and ( η 5 -C 5 Me 4 CH 2 CH 2 EMe)( η 5 -C 5 Me 4 CH 2 CH 2 E′Me)ZrCl 2 (E = O, S; E′ = O, S) with Mg/Hg in THF leads unexpectedly to the products of OMe and SMe bond cleavage ( η 5 , σ -C 5 Me 4 CH 2 CH 2 E)( η 5 -C 5 Me 5 )ZrMe (E = O, S), ( η 5 , σ -C 5 Me 4 CH 2 CH 2 E)( η 5 -C 5 Me 4 CH 2 CH 2 E′Me)ZrMe (E = O, S; E′ = O), and ( η 5 , σ -C 5 Me 4 CH 2 CH 2 S) 2 Zr respectively. The crystal structure of ( η 5 , σ -C 5 Me 4 CH 2 CH 2 S) 2 Zr was established by X-ray analysis. At that same time the reduction of (ηsu5-C 5Me 4 CH 2 CH 2 EMe)(η 5 -C 5 Me 5 )ZrCl 2 (E> = O, S) under 1 atm of CO gives either only the dicarbonyl derivative ( η 5 -C 5 Me 4 CH 2 CH 2 EMe) ( η 5 -C 6 Me 5 )Zr(CO) 2 (E = O) or a complex mixture of products (E = S).