Cross-coupling reactions of gold(I) alkynyl and polyyndiyl complexes

Gold(I) alkynyl complexes are shown to efficiently couple with aryl iodides under mild conditions in the presence of both Pd(II) and Cu(I) co-catalysts. The reaction is not gold catalysed, but rather the Au(I) centre serves to transfer the alkynyl moiety to Cu(I), which then enters the conventional Sonogashira cycles. Using this method, a small range of 1,4-disubstituted diynes, including examples of differentially substituted compounds ArCCCCAr′, have been prepared directly from [(Ph3P)AuCCCCAu(PPh3)] and aryl iodides ArI.

Gold(I) alkynyl and butadiyndiyl complexes smoothly cross couple with aryl iodides in the presence of PdCl2(PPh3)2 and CuI to afford a range of 1,2-diarylacetylenes and 1,4-diarylbuta-1,3-diynes.Figure optionsDownload as PowerPoint slideHighlights
► Gold(I) alkynyl complexes easily couple with aryl iodides.
► [CuI] and [PdCl2(PPh3)2] are effective catalysts.
► The coupling reactions proceed at moderate temperatures, in ethereal solvents.