CRYSTAL-STRUCTURE OF TRIPHENYLPHOSPHINE OXIDE OXALIC-ACID BENZENE

Triphenylphosphine oxide oxalic acid benzene (TPPO . OA . B), 2(C6H5)3 PO . (COOH)2 . C6H6, MW = 724.77, triclinic, P1BAR, a = 9.102(7), b = 13.593(6), c = 8.757(4) angstrom, alpha = 102.54(4), beta = 106.84(6), gamma = 70.74(5)-degrees, V = 970.06 angstrom, Z = 1, D(c) = 1.241 Mg . m-3, lambda(MoKalpha) = 0.71069 angstrom, mu = 1.19 cm-1, F(000) = 380, R = 0.057 for 2270 observed reflections and 234 variables. The pr esence of benzene in TPPO . OA . B has the effect of limiting the rota tion freedom of phenyl groups and reducing lattice symmetry compared t o that in TPPO . OA.