MESO-(1,1,4,7,10,10-HEXAPHENYL-1,4,7,10-TETRAPHOSPHADECANE-P,P',P'',P''') PLATINUM(II) BIS(TETRAPHENYLBORATE)

meso-[Pt(C42H42P4)][B(C24H20)]2.3CH2Cl2, M(r) = 1759.05, monoclinic, P2(1)/c, a = 15.761 (1), b = 28.731 (3), c = 20.832 (2) angstrom, beta = 114.967 (6)-degrees, V = 8551.80 angstrom3, Z = 4, D(m) 1.38, D(x) = 1.366 Mg m-3, lambda(Cu K-alpha) = 1.5418 angstrom, mu = 5.921 mm-1, F(000) = 3584, T = 283 K, final R = 0.080 for 7308 observed reflections. The X-ray structure analysis shows a slightly distorted square-planar coordination of the Pt atom by the P atoms. All four P atoms are located within a plane (maximum deviation 0.016 angstrom). The Pt atom is 0.161 angstrom out of this plane. The Pt-PPh bonds [2.274 (4) angstrom] are significantly shorter than the Pt-PPh2 bonds [2.327 (4) angstrom]. The PhP-Pt-PPh2 angles and the PhP-Pt-PPh angle are constrained to about 85-degrees (mean value 84.3, DELTA(max) 0.7-degrees). The Ph2P-Pt-PPh2 angle is wide open [105.8 (2)-degrees]. The thermodynamic destabilization of the square-planar arrangement of the title compound is compared with the destabilization of the corresponding chiral form and differences are discussed. Short intramolecular contact distances lead, in both cases, to the occurrence of related five-coordinate trigonal-bipyramidal and distorted tetrahedral compounds, thus releasing the strain of a planar P4 configuration.