Syntheses and ligand interconversions of copper(II) derivatives of the metalloligand [Pt 2(μ-S) 2(PPh 3) 4]

Abstract

The reactivity of the metallolig and [Pt 2(μ-S) 2(PPh 3) 4] towards a variety of copper(II)-ligand systems has been studied. Reaction of [Pt 2(μ-S) 2(PPh 3) 4] with copper(II) halide complexes [CuCl 2L] (L = 2,2′-bipyridine and 1,10-phenanthroline) gave trinuclear dicationic products [Pt 2(μ-S) 2(PPh 3) 4CuL] 2+, and the 8-hydroxyquinolinate (hq) complex [Cu(hq) 2] gave [Pt 2(μ-S) 2(PPh 3) 4Cu(hq)] +, isolated as their BP 4 - or PF 6 - salts. Related cationic complexes with other ancillary amine ligands (1,2-diaminoethane, 1,2-diaminopropane, 1,2-diaminocyclohexane) were obtained by reactions of [Pt 2(μ-S) 2(PPh 3) 4] with CuCl 2 and the amine. In contrast, reaction of [Pt 2(μ-S) 2(PPh 3) 4] with CuCl 2 and NH 3 in methanol gave the intensely blue methoxy-bridged dicopper complex [{Pt 2(μ-S) 2(PPh 3) 4Cu(OMe)} 2] 2+, isolated as its hexafluorophosphate salt. Copper β-diketonate complexes reacted with [Pt 2(μ-S) 2(PPh 3) 4] giving [Pt 2(μ-S) 2(PPh 3) 4Cu(β- diketonate)] +PF 6 - complexes, with the CH 3COCHCOCH 3 (acac) and CF 3COCHCO(2-thienyl) (tta) derivatives characterised by X-ray structure determinations. The local Cu(II) environment ranges from distorted square-planar to an intermediate form of square-planar and tetrahedral. The β-diketonate derivatives show varying stability towards methanolysis, giving [{Pt 2(μ-S) 2(PPh 3) 4Cu(OMe)} 2] 2+. © The Royal Society of Chemistry 2005.