SYNTHESIS AND CHARACTERIZATION OF COMPOUNDS CONTAINING THE AS(SIME3)2 BRIDGING GROUP - CRYSTAL-STRUCTURES OF [TERT-BU2GAAS(SIME3)2]2 AND TERT-BU2GAAS(SIME3)2GA(TERT-BU)2CL

tBu2GaCl reacts with LiAs(SiMe3)2.2thf (1:1 mole ratio) to yield I, which on reaction with tBu2GaCl (1:2 mole ratio) affords II quantitatively. [tBu2GaAs(SiMe3)2]2 (I) and tBu2 activate GaAs(SiMe3)2Ga(tBu)2Cl (II) were not produced from reaction mixtures of tBu2GaCl with (Me3Si)3As (1:1 and 2:1 mole ratio mixtures) and only starting materials were recovered. Compound II is the fifth example of a compound containing the activate Ga-As -Ga-X (X = Cl, Br) core, and the second wherein the organogallium four-membered ring with arsenic, halogen mixed-bridging is not puckered. In addition to partial elemental analyses and NMR spectroscopic characterization data, the molecular structures of I and II have been elucidated by single-crystal X-ray diffraction methods. Crystal data I: monoclinic, space group C2/m(C3 2h), a = 18.188(2) angstrom, b = 13.017(1) angstrom, c = 9.916(1) angstrom, beta = 118.54(1)-degrees, V = 2062.4(8) angstrom 3, Z = 2; II: monoclinic, space group C2/c(C6 2h), a = 20.872(4) angstrom, b = 9.798(1) angstrom, c = 19.397(4) angstrom, beta = 124.13(2)-degrees, V = 3284(2) angstrom 3, Z = 4.