Four novel mononuclear and polynuclear Cu(I) thiosaccharinates with triphenylphosphane and bis(diphenylposphino)methane. Synthesis and structural study of Cu 4(tsac) 4(PPh 3) 3, Cu(tsac)(PPh 3) 2, Cu 4(tsac) 4(dppm) 2, and Cu 2(tsac) 2(dppm) 2

Abstract

Four new ternary complexes of copper(I) with thiosaccharin and phosphanes were prepared. The reaction of [Cu 4(tsac) 4(CH 3CN) 2] ( 1) (tsac: thiosaccharinate anion) with PPh 3 in molar ratios Cu(I)/PPh 3 1:075 and 1:2 gave the complexes [Cu 4(tsac) 4(PPh 3) 3] · CH 3CN ( 2) and Cu(tsac)(PPh 3) 2 ( 3), respectively. The reaction of 1 with Ph 2PCH 2PPh 2 (dppm) in molar ratios Cu(I)/dppm 2:1 and 1:1 gave the complexes [Cu 4(tsac) 4(dppm) 2] · 2CH 2Cl 2 ( 4) and [Cu 2(tsac) 2(dppm) 2] · CH 2Cl 2 ( 5), respectively. All the compounds have been characterized by spectroscopic and X-ray crystallographic methods. Complex 2 presents a tetra-nuclear arrangement with three metal centers in distorted tetrahedral S 2NP environments, the fourth one with the Cu(I) ion in a distorted trigonal S 2N coordination sphere, and the tsac anions acting as six electron donor ligands in μ 3-S 2N coordination forms. Complex 3 shows mononuclear molecular units with copper(I) in a distorted trigonal planar coordination sphere, built with the exocyclic S atom of a mono-coordinated thiosaccharinate anion and two P-atoms of triphenylphosphane molecules. With dppm as secondary ligand the structures of the complexes depends strongly on the stoicheometry of the preparation reaction. Complex 4 has a centrosymmetric structure. Two triply bridged Cu 2(tsac) 2(dppm) units are joined together by the exocyclic S-atoms of two tsac anions acting effectively as bridging tridentate ligands. Complex 5 is conformed by asymmetric dinuclear moieties where the two dppm and one tsac ligands bridge two Cu(I) atoms and the second tsac anion binds one of the metal centers through its exocyclic S-atom.