Photo-driven reduction/cyclization of nitroarenes via electron donor–acceptor complexes: a novel method for the acquisition of N-heterocycles

Abstract

A method based on an electron donor–acceptor (EDA) complex is presented for the one-step reduction/cyclization of nitroarenes to obtain N-heterocycles. This photo-mediated mode showcases the versatility of amines, which act as electron donors in assembling photosensitive species and serve as C1 synthons in C–N bond formation. In addition to its excellent tolerance towards various functional groups, this strategy exhibits remarkable applicability for the late-stage modification of drug molecules, delivering 26 examples of benzimidazoles and 29 examples of quinazolinones. Meanwhile, it displays a preferable EcoScale score and is considered acceptable in terms of economic viability and safety, aligning with the principles of green chemistry. Overall, this metal-free method offers controllable synthesis conditions, employs scalable flow technology with high space–time efficiency and demonstrates successful gram-scale application, thereby highlighting its significant potential for constructing bioactive N-heterocycles.