CRYSTAL AND MOLECULAR-STRUCTURES OF THE ADDUCTS OF TRI-PARA-TOLYLTIN CHLORIDE, BROMIDE AND IODIDE WITH 4,4'-BIPYRIDINE

The structures of the three adducts [(p-tolyl),SnX]2.4,4'-bipyridine (X = Cl, Br, I), have been established by X-ray diffraction techniques. The complexes are monoclinic, space group P2(1)/c and Z=2. The cell parameters are: a = 13.262(2), b = 11.382(2), c = 17.029(2) angstrom and beta = 110.050(11)-degrees for X = Cl; a = 13.103(3), b = 11.351(2), c = 17.607(4) angstrom and beta = 110.050(16)-degrees for X=Br; a = 12.867(3), b = 11.389(4), c = 18.496(4) angstrom and beta = 110.050(11)-degrees for X = I. The complexes are binuclear with a bridging 4,4'-bipyridine. The tin is in a trigonal bipyramidal environment with the p-tolyl groups on the equator and the X atom and an N of the bipyridine on the axis. The Sn-N bond distances are 2.668(3), 2.653(3) and 2.655(7) angstrom, for X = Cl, Br and I, respectively. The Sn-X bond distances are 2.452(2), 2.691(1) and 2.830(1) angstrom, for X = Cl, Br and I, respectively.