Integrating Olefin Carboamination and Hofmann‐Löffler‐Freytag Reaction by Radical Deconstruction of Hydrazonyl N−N Bond
Si‐Pei Hu, Chen‐Hui Gao, Tuming Liu, Bing‐Yang Miao, Hong‐Chen Wang, Wei Yu, Bing Han
Abstract
Abstract As a type of elementary organic compounds containing N−N single bond, hydrazone involved chemical conversions are extremely extensive, but they are mainly limited to N 2 ‐retention and N 2 ‐removal modes. We report herein an unprecedented protocol for the realization of division utilization of the N 2 ‐moiety of hydrazone by a radical facilitated N−N bond deconstruction strategy. This new conversion mode enables the successful combination of alkene carboamination and Hofmann‐Löffler‐Freytag reaction by the reaction of N ‐homoallyl mesitylenesulfonyl hydrazones with ethyl difluoroiodoacetate under photocatalytic redox neutral conditions. Mechanism studies reveal that the reaction undergoes a radical relay involving addition, crucial remote imino‐N migration and H‐atom transfer. Consequently, a series of structurally significant ϵ‐ N ‐sulphonamide‐α,α‐difluoro‐γ‐amino acid esters are efficiently produced via continuous C−C bond and dual C−N bonds forging.