摘要:
Reaction of bis(2-methoxymethylphenyl)magnesium (1a) with Cp(2)TiCl(2) in THF affords Cp(2)Ti[2-CH3OCH2C6H4] (3) and 2,2'-bis(methoxymethyl)biphenyl in high yield. The crystal structure of 3 has been determined and is the first structure of a Ti(III) compound in which the Ti atom is intramolecularly coordinated by oxygen. Two chemically identical and conformationally only slightly different residues were found to be present in the unit cell of 3. Compound C18H19OTi (3) crystallizes in the monoclinic space group Pc (no. 7) with a = 13.0248(8), b = 7.7769(5), c = 14.8491(7)Angstrom, beta = 106.448(4)degrees, V = 1442.55(15)Angstrom(3), Z = 4. The structure refinement converged to R1 = 0.0478 for 4891 F-o)4 sigma(F-o) and wR2 = 0.0968 for all 6600 unique data, S = 1.010. The structure shows a pseudotetrahedral coordination around the Ti atom by two eta(5)-cyclopentadienyl groups, one carbon of the aryl ligand (Ti-C 2.19 Angstrom) and an oxygen atom of the methoxymethyl group. The Ti-O distance of 2.20 Angstrom is 1.48 Angstrom shorter than the expected van der Waals distance, which indicates a strong interaction between Ti and O. Reaction of bis(2-N,N-dimethylaminomethylphenyl)magnesium (1b) and Cp(2)TiCl(2) affords in a similar fashion Cp(2)Ti[2-(CH3)(2)NCH2C6H4] (4) and 2,2'-bis(N,N-dimethylaminomethyl)biphenyl.