Pyrrolidine dithiocarbamates of Pd(II)

The dithioester (CH2)4NCS2CH3 (PyDTM, 1-pyrrolidinecarbodithioate methyl ester) has been prepared by reaction of the parent ammonium salt NH4PyDT ðPyDT 1⁄4 ðCH2Þ4NCS 2 Þ with methyl iodide in water/ethanol. The reaction of PyDTM with PdCl2 allowed to synthesize either [PdCl2(PyDTM)], in which the ligand is chelated by both sulfur atoms, or [PdCl2(PyDTM)2], in which the ligand acts as monodentate through the thiocarbonyl sulfur. Thermal degradation of [PdCl2(PyDTM)] yielded the [PdCl(PyDT)]n species as an intermediate, which, in the presence of donors as chloride ions or dimethyl sulfoxide (DMSO), gave the complexes [PdCl(PyDT)(DMSO)] and NR4[PdCl2(PyDT)]. Moreover, PyDTM was found to react with various [PdCl(dithiocarbamato)]n intermediates to form the mixed species [PdCl(dithiocarbamato)(PyDTM)], whose thermal degradation yielded the [Pd(dithiocarbamato)(PyDT)] complexes. The behaviour of the prepared compounds in either solution or solid phase has been described on the basis of IR and proton NMR spectra and thermogravimetric analysis (TG and DTA). 2004 Elsevier B.V. All rights reserved.