Differing coordination modes of (O-alkyl)-p-ethoxyphenyldithiophosphonato ligands in copper(I), silver(I) and gold(I) triphenylphosphine complexes

The three (O-methyl)-p-ethoxyphenyldithiophosphonato triphenylphosphine complexes of copper, silver and gold, [(Ph3P)(n)M {S2P(OMe)C6H4OEt-p}] (M=Cu, n=2; M=Ag, Au, n=1) investigated structurally by X-ray diffraction exhibit remarkable structural differences. The copper compound is a four-coordinate chelate monomer with Cu-S 2.4417(6) and 2.5048(6) angstrom; P-Cu-S 104.24(2)-114.01(2)degrees; Cu-S-P 82.49(3)degrees and 80.85(2)degrees. The silver compound is a cyclic dimer with bridging dithiophosphonato ligands and three-coordinate silver atoms [Ag-S 2.5371(5) and 2.6867(5) angstrom; P-Ag-S 122.88(2)degrees and 122.17(2)degrees; Ag-S-P 89.32(2)degrees and 103.56(2)degrees]. The gold compound is monomeric with linear dicoordinate gold [Au-S 2.3218(6) angstrom; P-Au-S 177.72(2)degrees, Au-S-P 100.97(3)degrees].