Synthesis, structural characterization, and reactivity of (Me3CCH2)2GaAs(SiMe3)2Ga(CH2CMe3)2Cl, [(Me3CCH2)2GaAs(SiMe3)2]2, and (Me3CCH2)2Ga(Cl)•As(SiMe3)3

Reaction of 2 equiv of (Me3CCH2)2GaCl with (Me3Si)3As affords (formula omitted) (1), the fourth example of a compound containing the Ga-As-Ga-X (X = Cl, Br) core, but the first wherein the organogallium four-membered ring with arsenic/halogen mixed bridging is not puckered. Compound 1, as well as (Me3CCH2)2GaCl, reacts with LiAs(SiMe3)2•2THF (1:1 mole ratio) to produce the common product [(Me3CCH2)2GaAs(SiMe3)2]2 (2), which on reaction with (Me3CCH2)2GaCl (1:2 mole ratio) gives 1 quantitatively. Mixing (Me3CCH2)2GaCl and (Me3Si)3As in a 1:1 mole ratio yields the adduct (Me3CCH2)2Ga(Cl)•As(SiMe3)3 (3). Thermolysis of 3 did not afford 2, nor did its reaction with an additional 1 equiv of (Me3CCH2)2GaCl lead to 1 as the predominate product. Various physical and spectroscopic characterization data are presented for compounds 1–3, as well as the results of their X-ray crystal structure determinations. Crystal data: 1, monoclinic, space group P21/(C⁵2h), a = 12.412 (1) Å,b = 17.306 (1) Å, c = 20.238 (2) Å, β = 119.34 (1)°, V = 3790 (1) ų, Z = 4; 2, monoclinic, space group P2/c (C⁴2h), a = 12.180 (1) Å, b = 12.744 (1) Å, c = 19.618 (2) Å, β = 128.43 (1)°, V = 2386 (1) ų, Z = 2; 3, monoclinic, space group P21/c (C⁵2h), a = 12.486 (1) Å, b = 12.544 (1) Å, c = 19.985 (2) Å, β = 101.73 (1)°,V = 3065(1) ų, Z = 4. © 1992, American Chemical Society. All rights reserved.

Duke Scholars

Author Andrew T. McPhail Chemistry