SYNTHESIS AND CHARACTERIZATION OF BRIDGED DIMERIC AND TRIMERIC GROUP 13/15 COMPLEXES CONTAINING PRIMARY PHOSPHIDO [((T)BU)PH]- AND ARSENIDO [((T)BU)ASH]- UNITS

Addition of the primary phosphine tBuPH2 or the primary arsine tBuAsH2 to tBu3M (M = Ga, Al) followed by heating or photolysis affords the complexes [tBu2M(mu-E(tBu)H)]n (1: M = Ga, E = P; n = 2; 2, M = Al, E = P, n = 2; 3, M = Ga, E = As, n = 3; 4, M = Al, E = As, n = 3). For each compound, the degree of association was assessed on the basis of H-1, P-31, C-13 NMR and mass spectroscopy. The anti-isomer of 1 (1a) was also characterized by X-ray crystallography. Crystal data for la: C24H56Ga2P2, monoclinic, space group C2/m, a 17.124(7), b 11.755(7), c 8.700(3)angstrom, V 1561.94(15) angstrom3, Z = 4, D(calc) 1.157 g cm-3, mu(Mo Kalpha) 18.3 cm-1. A total of 1501 unique reflections was measured over the range 3.0 less-than-or-equal-to 2theta less-than-or-equal-to 50.0-degrees (theta-2theta scan mode) and 1263 of these with I > 3sigma(I) were used in the refinement to afford final R and R(w) values of 0.059 and 0.070, respectively.