Gold-Catalyzed Amide/Carbamate-Linked N,O-Acetal Formation with Bulky Amides and Alcohols.

A gold-catalyzed N,O-acetal formation was established to construct an amide/carbamate-linked N,O-acetal substructure with bulky alcohols. The acyliminium cation species generated from o-alkynylbenzoic acid ester in the presence of a gold catalyst is highly reactive and underwent nucleophilic attack of various bulky alcohols and phenols at room temperature under neutral conditions, leading to the corresponding N,O-acetals in yields of 34-89% with good functional group tolerance.