Synthetic, structural and vibrational spectroscopic studies in bismuth(III) halide/N,N'-aromatic bidentate base systems. IV Bismuth(III) halide: N,N'-bidentate ligand (1:1) systems

Room-temperature single-crystal X-ray studies are recorded for a number of adducts of BiX3 and N,N'-bidentate ligand (2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen)), devoid of coordinated solvent. BiBr3/bpy/MeCN (1:1:1) is triclinic , a 12.129(2), b 9.955(4), c 7.748(1) Angstrom, alpha 73.14(2), beta 77.34(1), gamma 69.79(2)degrees, Z = 2; conventional R on \F\ was 0.036 for N-o 2252 independent 'observed' (I > 3 sigma(I)) reflections. The phen analogue is isomorphous, a 11.586(3), b 10.839(6), c 7.769(10) Angstrom, alpha 73.70(7), beta 76.67(7), gamma 70.34(4)degrees, Z = 2, R 0.042 for N-o 800. BiI3/bpy (1:1) is triclinic, , a 11.742(4), b 9.261(1), c 8.261(3) Angstrom, alpha 86.46(2), beta 71.48(3), gamma 67.25(2)degrees, Z = 2, R 0.043 for N-o 1164. All complexes are centrosymmetric binuclear [(N,N'-bidentate)X2Bi(mu-X)(2)BiX2(N,N'-bidentate)] with six-coordinate pseudo-octahedral bismuth(III). Attempts to produce a chloride analogue have resulted, in the case of N,N'-bidentate = bpy, in a novel adduct of BiCl3/bpy 1:1.5 stoichiometry, monoclinic, P2(1)/c, a 9.377(8), b 17.699(5), c 21.58(1) Angstrom, beta 107.82(6)degrees, Z = 8, R 0.055 for N-o 1804. The complex is [(bpy)(2)Cl2Bi(mu-Cl)BiCl3(bpy)], containing seven- and six-coordinate bismuth. Bands in the far-infrared spectra due to the nu(BiX) vibrations in [(bpy)(2)Cl2Bi(mu-Cl)BiCl3(bpy)] and [(bpy)I2Bi(mu-I-2)BiI2(bpy)] are assigned and discussed in relation to the structures of the complexes.