SYNTHESIS AND STRUCTURE OF A POLYNUCLEAR COMPLEX WITH A FRAMEWORK CONSISTING OF GERMANIUM, BISMUTH AND PLATINUM ATOMS

Article abstract of DOI:10.1016/S0022-328X(00)83853-X

The structure of the product of the interaction of (C6F5)2GeH2 with Et3Bi has been defined more precisely by X-ray analysis.The heteroelemental framework of this compound is found to be a trigonal bipyramid in which the two apical Bi atoms are bonded by three bis(pentafluorophenyl)germyl bridges.The symmetry of the framework is D_3h.The average value of the Ge-Bi bond length is 2.739(1) Angstroem.The average values of the Ge-Bi-Ge and Bi-Ge-Bi angles are equal to 72.11(4) and 93.94(4)^o, respectively.Reaction of the compound with Pt(PPh3)3 yields the unusual 6-nuclear complex <(C6F5)2Ge>3Bi2Pt(PPh3)2.It was shown by an X-ray study that the two Ge, two Bi and Pt atoms form a nonplanar cycle in this complex.Moreover, the Bi atoms are bonded by the (C6F5)2Ge bridged group.The symmetry of the heavy atom framework is somewhat disordered from C_s.The Pt atom has a square-planar coordination.The Ge-Pt and Bi-Pt bond lengths are equal to 2.466(3) and 2.759(3) Angstroem, respectively.The Ge-Bi bond lengths are changed in the range from 2.695(5) to 2.774(6) Angstroem depending on their positions in the molecule.The GeBiGe angles in the 4-member GeBiGeBi cycle are 87.6(2) and 70.9(2)^o, and the BiGeBi angles are 98.3(2) and 98.5(2)^o.The GeBiGe angle in the 5-member PtGeBiGeBi cycle is equal to 87.6(2)^o, and the GeBiPt angle is 100.8(1)^o.The pentafluorophenyl and triphenylphosphine ligands have the usual geometry.