Synthesis of N,N '-bis(thioether)-functionalized imidazolium salts: their reactivity towards Ag and Pd complexes and first S,C-NHC,S free carbene

The synthesis of bis(thioether)-functionalized imidazolium salts, the characterisation of the first S,C-NHC,S free carbene ligand and the corresponding Ag(I) and Pd(II) functional carbene complexes are reported. The latter have been prepared from the isolated Ag(I) carbene complexes using the transmetallation procedure or by reaction of the imidazolium salts with [PdCl2(COD)], followed by deprotonation of the intermediate in which both thioether functions are coordinated to Pd(II).