Synthesis and characterization of cyclometallated palladium(II) and platinum(II) complexes with amide-thiolate ligands

The redox reaction of bis(2-benzamidophenyl) disulfide (H2L-LH2) with [Pd(PPh3)4] in a 1:1 ratio gave mononuclear and dinuclear palladium(II) complexes with 2-benzamidobenzenethiolate (H2L−), [Pd(H2L-S)2(PPh3)2] (1) and [Pd2(H2L-S)2 (μ-H2L-S)2(PPh3)2] (2). A similar reaction with [Pt(PPh3)4] produced only the corresponding mononuclear platinum(II) complex, [Pt(H2L-S)2(PPh3)2] (3). Treatment of these complexes with KOH led to the formation of cyclometallated palladium(II) and platinum(II) complexes, [Pd(L-C,N,S)(PPh3)]− ([4]−) and [Pt(L-C,N,S) (PPh3)]− ([5]−). The molecular structures of 2, 3 and [4]− were determined by X-ray crystallography.