AuPPh3Cl/AgOTf-catalyzed reaction of terminal alkynes: nucleophilic addition to activated CO bond

Terminal alkynes, under Au-catalyzed conditions, react with aromatic aldehyde diethyl acetals, affording propargylation products through CO bond addition. Furthermore, AuPPh3Cl/AgOTf-catalyzed three-component reaction of aldehydes, alkynes, and triethyl orthoformate is developed. Gold alkynilides are supposed to be reactive intermediates in these reactions.