This review summarized the recent developments in metal catalyzed or mediated cyclization/functionalization of alkynes to construct isoxazoles.

A palladium-catalyzed ionic liquids-accelerated oxidative cascade annulation/functionalization of acetylinic oximes with unactivated long-chain enols under aerobic conditions was accomplished. The newly developed protocol provides the rapid and straightforward synthetic strategy...

During the past decades, alkynes chemistry has attracted considerable attention owing to their unique and idiographic nucleophilic and electrophilic properties in transition-metal-catalyzed chemical transformations. Among the various metal catalysts, palladium...

Main observation and conclusion A novel and viable palladium‐catalyzed sequential cyclization/functionalization of alkynone O‐methyloximes with unactivated vinyl ethers under aerobic conditions was described. The structure of the products could be successfully controlled by varying the nature of the substituents of the vinyl ethers. This new approach provides a convenient and straightforward synthetic protocol for the preparation of structurally diverse 4‐(1‐alkoxyvinyl)‐isoxazoles and 4‐vinylisoxazoles in moderate to good yields with highly regioselectivity. Remarkably, this protocol can be performed on a gram scale, showing the promising application in synthetic and pharmaceutical chemistry.

A novel palladium-catalyzed three-component cascade arylthiolation for the assembly of 3-sulfenylindoles and 3-sulfenylbenzofurans is described, with aryldiazonium salts as the ideal S-arylation sources.