PI-ARENE COMPLEXES .8. EARLY/LATE HETEROBIMETALLIC COMPLEXES OF CHROMIUM WITH SIGMA,PI-BRIDGED ARENE LIGANDS

New heterobimetallic and trimetallic complexes of titanium, [Ti(eta(5)-C5H5)2(Cl)(mu-eta(1):eta(6)-RC6H4)Cr(CO)3] (R = H (1), omicron-F (2), p-CH3 (3), m-CH3 (4), [Ti(eta(5)-C5H5)2(Cl)(mu-eta(1):eta(6)-C6Me5CH2)Cr(CO)3] (5), and [(mu-{Ti(eta(5)-C5H5)2}){(eta(1):eta(6)-RC6H4)Cr(CO)3}2] (R = H (6), p-CH3 (7), and gold, [Au(PPh3)(mu-eta(1):eta(6)-RC6H4)Cr(CO)3] (R = H (9), o-F (10)), were prepared by the addition of the transition-metal halide Ti(eta(5)-C5H5)2(Cl)2 or Au{PPh3}Cl to a tetrahydrofuran solution of the appropriate lithiated (pi-arene)tricarbonylchromium(0) substrate. The characterization of the bi- and trinuclear products by analytical and NMR, IR, and mass spectral data is supported by X-ray studies of the fluorobenzene (2) and toluene (3) derivatives, which confirm that the phenyl ligand is pi-coordinated to the chromium tricarbonyl group, as well as sigma-bonded to the bent metallocene. Crystals of 2 were monoclinic, P2(1)/n, with a = 10.431 (4) angstrom, b = 12.506 (13) angstrom, c = 13.905 (3) angstrom, beta = 106.38 (2)-degrees, and Z = 4. Crystals of 3 were orthorhombic, Pbca, with a = 14.138 (2) angstrom, b = 13.625 (2) angstrom, c = 19.229 (6) angstrom, and Z = 8.