Ni-Catalyzed Cycloisomerization between 3‑Phenoxy Acrylic Acid Derivatives and Alkynes via Intramolecular Cleavage and Formation of the C–O Bond To Give 2,3-Disubstituted Benzofurans

Reactions based on transition-metal-catalyzed C–O bond cleavage have attracted much attention as a new synthetic method. Until now, several intermolecular reactions via C–O bond cleavage of aryl ethers, alkenyl ethers, esters, and others have been reported. Here we report an unprecedented C–O bond cleavage of 3-phenoxy acrylic acid derivatives, followed by intramolecular C–O bond formation with alkynes. This reaction gave 2,3-disubstituted benzofurans having useful functional groupssilyl substituents and acrylic acid derivativesat the 2- and 3-positions, respectively. This report also described theoretical (DFT) insights into the mechanism.