C–H Functionalization of Heteroaromatic N-Oxides

Heteroaromatic N-oxides have received wide attention as useful synthetic intermediates, various functional molecules, and biologically active compounds. On the other hand, C–H functionalization of heteroaromatic N-oxides is one of the key methods of organic synthesis for selectively introducing substituents in heteroaromatic rings. Organometallic chemistry has played an important role in selective transformation of organic molecules, but recently developed metal-free processes are regarded as attractive methodologies from a viewpoint of environmentally benign organic synthesis. Recent advances in the field of nucleophilic C–H functionalization of heteroaromatic N-oxides using metal-free processes are discussed.