STRUCTURES OF CHLOROHYDROXOBIS(PENTAMETHYLCYCLOPENTADIENYL)TANTALUM(V) TRIFLUOROMETHANESULFONATE (TRIFLATE) AND DIHYDROXOBIS(PENTAMETHYLCYCLOPENTADIENYL)-TANTALUM(V) TRIFLATE

[Ta(C10H15)2(Cl)(OH)][CF3SO3] (I), M(r) = 652.94, monoclinic, P2(1)/n, a = 9.965 (7), b = 18.796 (5), c = 13.269 (3) angstrom, beta = 94.02 (3)-degrees, V = 2479.2 (19) angstrom 3, Z = 4, D(x) = 1.75 g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 46 cm-1, F(000) = 1288, room temperature, R = 0.107 for 3702 reflections with F(omicron)2 > 0 [R = 0.053 for 2094 reflections with F(omicron)2 > 3-sigma(F(omicron)2)]. [Ta(C10H15)2(OH)2][CF3SO3] (II), M(r) = 634.49, triclinic, P1BAR, a = 10.052 (2), b = 10.111 (2), c = 12.739 (2) angstrom, alpha = 71.38 (2), beta = 78.21 (1), gamma = 77.40 (2)-degrees, V = 1184.7 (4) angstrom 3, Z = 2, D(x) = 1.78 g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 47 cm-1, F(000) = 628, room temperature, R = 0.032 for 4046 reflections with F(omicron)2 > 0 [R = 0.026 for 3664 reflections with F(omicron)2 > 3-sigma(F(omicron)2)]. Severe disorder of the triflate anion in (I) led to a less satisfactory structure, but cations in both compounds are well defined, with normal Ta-Cp* geometry. Ta-Cl 2.343 (4), Ta-O 1.853 (8) angstrom and Cl-Ta-O 96.4 (3)-degrees in (I); Ta-O 1.907 (6) angstrom and O-Ta-O 100.4 (2)-degrees in (II). Tantalum-bound OH groups are hydrogen bonded to triflate O atoms.