SYNTHESIS, NMR-STUDY, AND X-RAY STRUCTURE OF 2-(N-METHYL-N'-CYANO-N''-ETHYLGUANIDINO) THIOTRIPHENYLPHOSPHINEGOLD(I)

The reaction between cimetidine in a methanolic solution of KOH and a dichloromethane solution of PPh(3)AuCl affords a new compound with formula [L-Au-PPh(3)] (I) (L = 2-(N-methyl-N'-cyano-N ''-ethylguanidino)thiolate), the thiolato ligand resulting from cleavage of one of the thioether bonds of cimetidine. (I) has been characterized by elemental analysis, infrared, and H-1 and C-13 NMR spectroscopy. Single crystal x-ray structure determination shows that the gold atom is linearly coordinated by a phosphine ligand (Au-P 2.258(1) Angstrom) and by an S atom (Au-S 2.282(1) Angstrom) of the thiolato ligand. Crystal data: triclinic, space group P (1) over bar with a = 8.848(1), b = 11.343(3), c = 12.107(3) Angstrom, alpha = 87.63(1), beta = 85.24(1), gamma = 79.89(1)degrees, R = 0.024 for 3673 reflections with I > 3 sigma(I).