Synthesis, X-ray molecular structure analysis, and study on ligand scrambling reactions of new thiolatogold(I) complexes with various phosphines

Treatment of Au(PPh3)Cl, (AuCl)2(trans-dpen) and (AuCl)2(dppfe) with Sn(SPh)(n-Bu)3 and/or PhSH/KOH affords Au(PPh3)(SPh) (1), (AuSPh)2(μ-trans-dpen) (2), (AuSPh)2(μ-dppfe) (3), (AuSPh)(μ-trans-dpen)(AuCl) (4), and (AuSPh)(μ-dppfe)(AuCl) (5) in good yields. All these thiophenolates are characterized by single crystal X-ray analysis, 1H and 31P NMR spectroscopy. 1 forms tetramer through Au⋯Au interaction and π–π interaction between the phenyl group in SPh and one of the phenyl groups in PPh3 in the solid state. An infinite chain structure is formed for 2 through intermolecular aurophilicity and these chains are connected by partial overlap (π–π interaction) of neighboring phenyl groups in SPh to give two-dimensional networks in the solid state. Similar infinite chains are formed through aurophilicity, but two-dimensional networks are not formed for 4 in the solid state. No multidimensional structure is formed for 3 and 5 in the solid state. 1H and 31P NMR spectroscopy of CDC13 solutions of 2, 3, 4, and 5 has revealed that rapid ligand scrambling takes place for 4 and 5.