Brønsted acid enabled metal-free remote oxygenation and amidation of unstrained C–C bonds via 1,4-heteroaryl 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 bond formation via unstrained C–C bond cleavage in acyclic molecules 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, representing a novel paradigm for remote C(sp³)–heteroatom bond construction via C–C bond activation.