1.8 Nitrogen-Centered Radicals

Abstract

Nitrogen-containing compounds are prevalent in the key components of various functional materials and compounds such as pharmaceutical drugs. Therefore, it is extremely important to develop versatile synthetic methodologies capable of constructing C—N bonds in an efficient manner under milder reaction conditions. Apart from common ionic C—N bond-forming reactions (i.e., nucleophilic and electrophilic amination, as well as transition-metal-catalyzed C—N cross-coupling processes), leveraging of nitrogen-centered radicals for C—N bond-forming process has created another dimension to the modern synthesis of nitrogen-containing compounds. In particular, recent development of novel catalytic strategies and the design of new nitrogen-radical precursors have rendered their generation and use for C—N bond formation more practical and user-friendly for synthesis of wider array of nitrogen-containing compounds of potential use. This chapter highlights the latest developments in synthetic methods for C—N bond construction using nitrogen-centered radicals by showing selected reactions, mostly reported in the last five years, based on their structural and reactivity features as well as the method of radical generation.