Diaryl thioketones are selectively reduced with ytterbium metal to diarylmethanethiols, diarylmethanes or tetraarylethylenes, via thiometallacycle intermediates which undergo electrophilic coupling at thiocarbonyl carbon and sulfur.
Synthetic Utility of Umpoled Diaryl Thioketone−Lanthanoid Intermediates: Desulfurization, Cross Coupling with Electrophiles, and Desulfurizative Homocoupling