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 ArCtriple bond; length of mdashCCtriple bond; length of mdashCAr′, have been prepared directly from [(Ph3P)AuCtriple bond; length of mdashCCtriple bond; length of mdashCAu(PPh3)] and aryl iodides ArI.