ORGANOZINNVERBINDUNGEN XXXII. ZUR PHOTOCHEMISCHEN REAKTION VON KETONEN MIT TETRAMETHYL-1,2-BIS(PHENYLTHIO)DISTANNAN

Article abstract of DOI:10.1016/0022-328X(86)80114-0

The photolytic reductive dimerization of a number of diaryl and aryl alkyl ketones by means of the distannane Me2(PhS)Sn-Sn(SPh)Me2 gives the corresponding 1,3,2-dioxastannolanes which are easily hydrolyzed yielding pinakols.Several diketones react in the same way with C-C coupling.Depending on the type of carbonyl compound, the different mechanism either exclude or compete with one another.One reaction proceeds via a ketyl radical ArRC^.-OSn(SPh)Me2 and the bismetalated pinakol giving ultimately the five-membered ring and Me2Sn(SPh)2.However, with fluorinated acetones, a stannylenoid mechanism may be considered, and an organometallic 1,3-dipol RR'C^--O-Sn⁺Me2 is proposed as a shortlived intermediate.