SYNTHESIS OF GROUP-4 METAL-COMPOUNDS CONTAINING CYCLOPENTADIENYL LIGANDS WITH A PENDANT ALKOXIDE FUNCTION - MOLECULAR-STRUCTURE OF ([ETA(5)-ETA(1)-C5H4(CH2)(2)O]TICL2)(2) AND [ETA(5)-ETA(1)-C5H4(CH2)(3)O]TICL2

Trimethylsilylcyclopentadiene-siloxy ethers Me(3)SiC(5)H(4)(CH2),OSiMe (3) (n = 2, 3) react with TiCl4 to give (2-(cyclopentadienyl)-eth-1-ox y)titanium dichloride, [[eta(5): eta(1)-C5H4(CH2)(2)O]TiCl2](2) and (3 -(cyclopentadienyl)-prop-1-oxy)titanium dichloride [eta(5): eta(1)- C5 H4(CH2)(3)O]TiCl2, by release of two equivalents of Me(3)SiCl. Molecul ar structure determination shows that [[eta(5): eta(1)- C5H4(CH2)(2)O] TiCl2](2) is dimeric in the solid state with the alkoxide function bri dging two titanium centers, whereas [eta(5): eta(1)- C5H4(CH2)(3)O]TiC l2 is a monomer with a bidentate cyclopentadienyl-alkoxide ligand. [[e ta(5): eta(1)-C5H4(CH2)(2)O]TiCl2](2) crystallizes in the triclinic sp ace group <P(1)over bar> with a = 7.702(1) Angstrom, b = 7.942(2) Angs trom, c = 8.251(1) Angstrom, alpha = 71.39(1)degrees beta = 89.92(1)de grees, gamma = 61.25(2)degrees, V = 412.27(16) Angstrom(3) and Z = 1. The basic structure consists of a dimer molecule with a crystallograph ic center of inversion, coupled by two Ti-O-Ti bridges. Crystals of [e ta(5):eta(1)-C5H4(CH2)(3)O]TiCl2 are triclinic, space group <P(1)over bar> with a = 8.194(1), b = 11.002(1), c = 11.192(1) Angstrom, alpha = 84.339(5), beta = 88.035(5), gamma = 76.256(6)degrees, V = 975.2 Angs trom(3) and Z = 4. Two crystallographically independent molecules are present in the asymmetric unit.