PYRAZOLATE THIOCARBONYLRHODIUM COMPLEXES. X-RAY STRUCTURE OF 2

Article abstract of DOI:10.1016/S0022-328X(00)82568-1

The preparation and properties of complexes of general formulae ClO4 (HL=pyrazole (HPz), 3-methylpyrazole (H3-MePz), 3,5-dimethylpyrazole (H3,5-Me2Pz), PR3=triphenylphosphine, tricyclohexylphosphine) and <(PR3)2(CS)Rh(μ-Pz)AuPPh3>ClO4 are reported.Complexes of the first set react with potassium hydroxide to give 2 or RhPz(CS)(PR3)2 complexes.The structure of the complexes 2 has been determined by X-ray diffraction methods.The crystals are monoclinic, space group P2₁/c, with Z=4 in a unit cell of dimensions a=12.700(11), b=17.217(16), c=23.041(18) Angstroem, β=116.55(8)^o.The structure has been solved by Patterson and Fourier methods and refined by full-matrix least-squares to R=0.059 for 1978 independent reflections.The structure consists of dimeric complexes, in which each rhodium atom is in a square-planar environment being bonded to a carbon atom of a thiocarbonyl ligand, a phosphorus atom of a triphenylphosphine molecule and to two nitrogen atoms of pyrazolate ligands bridging the metal atoms.The dihedral angle of 71.1^o between such two square planes leads to a bent configuration with an intramolecular rhodium-rhodium distance of 3.220 Angstroem.The thiocarbonyl and triphenylphosphine ligands are in a trans disposition.