SYNTHESIS AND STRUCTURE OF TRINUCLEAR METHOXY-BRIDGED TITANIUM(III)-MAGNESIUM COMPLEXES - [(C(5)H(5-N)ME(N))(2)TI(MU-OME)(2)](2)MG (N=4 AND5)

The hydride complexes [(C(5)Me(5))(2)Ti(mu-H)(2)]Mg-2 (1) and [(C(5)HM e(4))(2)Ti(mu-H)(2)]Mg-2 (2) smoothly react with four equivalents of m ethanol to give the methoxy complexes [(C(5)Me(5))(2)Ti(mu-OMe)(2)]Mg- 2 (3) and [(C(5)HMe(4))(2)Ti(mu-OMe)(2)]Mg-2 (4), The X-ray crystal an alysis of 4 revealed a nearly linear arrangement of the metal atoms in an unsymmetrical molecule, The EPR spectra of the frozen toluene glas s of 3 and 4 showed the triplet state spectra with very similar zero f ield splitting of rhombic symmetry. The distance between the unpaired electrons in 4 was estimated from the value of D = 0.00958 cm(-1) to b e 6.43 Angstrom, in good agreement with the crystallographic Ti-III-Ti -III distance of 6.329(1) Angstrom. Complex 4 reacts with excess dibut yl magnesium to give a mixture of 2 and [(C(5)HMe(4))(2)Ti(mu-H])(2)Mg (mu-OMe)](2) (6). A mixture of 4 and methylalumoxane (1:100) did not i nduce the polymerization of ethylene.