A Photoredox-Catalyzed Approach for Formal Hydride Abstraction to enable C(sp3)–H Functionalization with Nucleophilic Partners (F, C, O, N, and Br/Cl)
Patricia Musacchio reports on the C(sp3)–H functionalization with nucleophilic partners supported by photoredox catalysis.
Carbocations are very reactive intermediates but are rarely present in C–H functionalization mechanisms, which are dominated by carbon radical and metal alkyl intermediates. It has been a goal for the lab of Professor Patricia Musacchio at the Worcester Polytechnic Institute (USA), ever since its inception as a new lab, to develop mild strategies that can ‘dismantle’ a C(sp3)–H bond all the way down to a carbocation, which formally means to remove a hydride from a C(sp3)–H bond. The group aimed for a simple alternative to a direct hydride abstraction by combining two reliable reaction processes – hydrogen-atom transfer (HAT) and oxidation of radicals, otherwise known as radical-polar crossover (RPC) – in one catalytic cycle and do it in a mild fashion.