Molecular gallium arsenide phosphide clusters prepared from AsP(3), P(4), and [{GaC(SiMe(3))(3)}(4)]

Treatment of AsP(3) with 0.75 equivalents of [{GaC(SiMe(3))(3)}(4)] resulted in selective insertion of three equivalents of {GaC(SiMe(3))(3)} into the three As--P bonds to give [As{GaC(SiMe(3))(3)}(3)P(3)] (1-As) with an intact cyclo-P(3) ring. This yellow compound has been characterized by NMR spectroscopy, combustion analysis, single-crystal X-ray diffraction, UV/Vis spectroscopy, Raman spectroscopy, and cyclic voltammetry (THF, 0.2 M [TBA][B(C(6)F(5))(4)]; TBA=tetrabutyl ammonium). Computational models of 1-As and the isomeric [P{GaC(SiMe(3))(3)}(3)AsP(2)] (1-P) have been investigated as well, revealing several interesting electronic features of these cage molecules. Following from the cyclic voltammetry studies of 1-As that highlight an irreversible two-electron reduction at -2.2 V versus Fc/Fc(+), treatment with one equivalent of [Mg(C(14)H(10))(thf)(3)] resulted in two-electron reduction to provide [As{GaC(SiMe(3))(3)}(3)P(3)Mg(thf)(3)] (2), in which the Mg(2+) ion has inserted into one of the P--P bonds of the cyclo-P(3) ring. It was also found that treatment of AsP(3) or P(4) with one equivalent of [{GaC(SiMe(3))(3)}(4)] resulted in formation of the quadruple insertion products [As{GaC(SiMe(3))(3)}(4)P(3)] (3) and [P{GaC(SiMe(3))(3)}(4)P(3)] (4), respectively.