Brønsted acid enabled metal-free remote oxygenation and amidation of unstrained C–C bonds via 1,4-group migration chaperoned radical-polar crossover

Abstract

C–C bond functionalization has emerged as a powerful tool for the skeleton editing of organic molecules. However, remote C(sp3)–O and C(sp3)–N bonds formation via unstrained C–C bond cleavage in acyclic molecules still remains challenging. Herein in this work, a Brønsted acid enabled metal-free remote oxygenation and amidation of NHPI esters via 1,4-group migration chaperoned radical-polar crossover has been established, affording a variety of heteroaryl-tethered alcohols, ethers and amides in moderate to good yields. This protocol also features mild conditions, good functional group tolerance and high regioselectivity, proving a novel paradigm for remote C(sp3)–heteroatom bond construction via C–C bond activation.