(Thio)(silyl)carbene and (seleno)(silyl)carbene gold(i) complexes from the reaction of bis(methylene)-λ4-sulfane and bis(methylene)-λ4-selane with chloro(dimethylsulfide)gold(i).

The dinuclear (thio)(silyl)carbene and (seleno)(silyl)carbene gold(I) complexes 1 and 2 were obtained from the reaction of two equivalents of AuCl(SMe2) with the stable bis(methylene)-λ4-chalcogenanes 3 and 4, respectively. The reaction proceeds under elimination of the chlorosilane moiety of 3 and 4. Complexes 1 and 2 were characterized by spectroscopic and x-ray diffraction (XRD) analyses. The 13C NMR signals for the carbene centers of 1 (309 ppm) and 2 (345 ppm) are by more than 150 ppm downfield shifted relative to those for other known (NHC)AuCl complexes. These results indicate that (chalcogeno)(silyl)carbenes, like (amino)(silyl)carbenes, belong to the push-spectator family of carbenes.