<scp>Palladium‐Catalyzed</scp>Sequential Cyclization/Functionalization of Oxime Ethers with Unactivated Vinyl Ethers for Tunable Assembly of Structurally Diverse Isoxazoles
Jianxiao Li, Zidong Lin, Dan He, Wanqing Wu, Huanfeng Jiang
Abstract
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.