ALCOHOLYSIS OF TITANIUM ALKOXIDES BY FLUOROALCOHOLS - SYNTHESIS, CHARACTERIZATION AND X-RAY CRYSTAL-STRUCTURE OF [TI(O-I-PR)2(OCH(CF3)2)2]2

Reaction of 2 equiv. of hexafluoro-2-propanol in hexane with tetrakis-isopropoxy titanium (IV) results in the formation of Ti(O-i-Pr)2[OCH(CF3)2]2, a volatile complex which has been characterized by a number of techniques, including X-ray crystallography [space group P2(1)/n; a = 9.786(3) angstrom, b = 18.393(6) angstrom, c = 10.755 angstrom, beta = 103.64(1)-degrees, Z = 2]. The molecule adopts a dinuclear structure in which oxygen atoms of isopropoxide ligands are asymmetrically bridging [1.900(2) and, 2 120(2) angstrom] between the titanium atoms. The coordination geometry about the titanium atoms is roughly that of a trigonal bipyramid with the short interactions of the bridging alkoxides occupying equatorial positions and the longer interactions occupying axial positions. The Ti-O distance [1.752(2) angstrom] of the terminal isopropoxy ligand is significantly shorter than the Ti-O distances [1.84(1) angstrom (avg)] of the terminal fluoroalkoxide ligands. NMR data and mass spectral data suggest that this complex is monomeric both in solution and in the gas phase.