TRIMETHYLGALLIUM BASED PHOSPHINOGALLANES - SYNTHESIS AND MOLECULAR-STRUCTURE OF [ME2GA-P(SIME3)2]2

The sterically demanding phosphinogallane [Me2Ga-P(SiMe3)2]2, prepared from reaction of trimethylgallium and tris(trimethylsilyl)phosphine i n toluene, has been characterized by partial elemental analyses, H-1 N MR and single crystal X-ray diffraction. The title compound crystalliz es in the space group P1BAR (No. 2) with unit cell dimensions a = 9.71 1(l), b = 9.857(l), c = 9.211(l) angstrom, alpha = 99.62(l), beta = 11 6.25(l), gamma = 76.28(l)-degrees, V = 766.3 angstrom3 and D(calc) = 1 .20 g cm-1 for Z = 1. Refinement converged at R = 0.037, R(w) = 0.046, based on 1606 observed reflections with intensities I > 3sigma(I). Th e independent Ga-P distance was determined to be 2.456(l) angstrom. Py rolysis of the dimer did not afford higher order phosphinogallanes.