Group 4 metallocene complexes incorporating vinyl or allyl substituted ansa ligands.: X-Ray crystal structures of [Zr{Me(CH2=CH)Si(η5-C5Me4)2}Cl2] [Zr{Me(CH2=CHCH2)Si(η5-C5H4)2}Cl2] and [Zr{Me(CH2=CHCH2)Si(η5-C5Me4)(η5-C5H4)}Cl2]

The vinyl and allyl substituted ansa-ligand precursors, Me(R)Si(C5H5)(2) (R=CH=CH2 (1), CH2CH=CH2 (2)) Me(R)Si(C5HMe4(C5H5) (R=CH=CH2 (5), CH2CH=CH2 (6)), and Me(R)Si(C5HMe4)(2) (R=CH=CH2 (7), CH2CH=CH2 (8)), and their lithium derivatives, Li-2{Me(R)Si(C5H4)(2)} (R=CH=CH2 (9), CH2CH=CH2 (10)), Li-2{Me(R)Si(C5Me4(C5H4)} (R=CH=CH2 (11), CH2CH=CH2 (12)), and Li-2{Me(R)Si(C5Me4)(2)} (R=CH=CH2 (13), CH2CH=CH2 (14)), have been prepared. The Group 4 metal complexes, [M{Me(R)Si(eta(5)-C5H4)(2)}Cl-2] (R=CH=CH2, M=Ti (15), Zr (16), Hf (17); R=CH2CH=CH2, M=Ti (18), Zr (19), Hf (20)), [M{Me(R)Si(eta(5)-C5Me4)(eta(5)-C5H4)}Cl-2] (R=CH=CH2, M=Ti (21), Zr (22), Hf (23); R=CH2CH=CH2, M=Ti (24), Zr (25), Hf (26)), [M{Me(R)Si(eta(5)-C5Me4)(2})Cl-2] (R=CH=CH2, M=Ti (27), Zr (28), Hf (29); R=CH2CH=CH2, M=Ti (30), Zr (31), Hf (32)), were synthesized from the reaction of the lithium ansa-derivative and the tetrachloride salts of the transition metal. The reactivity of some of the Group 4 metal complexes has been tested in hydrogenation and hydroboration processes. The molecular structures of 19, 25 and 28 have been determined by single crystal X-ray diffraction studies. (C) 2003 Elsevier Science B.V. All rights reserved.