Recent Advances in Nitrogen–Nitrogen Bond Formation

Abstract

Over the last decade, N–N bond formation as a synthetic strategy has emerged as a powerful key step in the construction of highly valuable heterocycles from easily obtained materials. This review focuses on recent methods used to build N–N bonds, classified by intra- and intermolecular reactions with various types of N–X (O, C, N, H) bond cleavage.1 I ntroduction2 Intramolecular N–N Bond Formation2.1 Cleavage of N–O Bonds2.2 Cleavage of N–C Bonds2.3 Cleavage of N–N Bonds2.4 Cleavage of N–H Bonds2.4.1 Construction of Pyrazole Derivatives2.4.2 Construction of Triazole Derivatives2.4.3 Construction of Indazole and Pyrazoline Derivatives2.4.4 Construction of Other N–N Bond Derivatives3 Intermolecular N–N Bond Formation4 Conclusion

Mechanistic insights into copper-catalyzed aerobic oxidative coupling of N–N bonds

“…6 Methods for N-N bond formation commonly involve oxidized nitrogen intermediates, such as those bearing N-OR or N-X (X ¼ halide) bonds, that react with an amine or other nitrogenbased nucleophiles to form the N-N bond. 1 Recent advances have led to alternative strategies that bypass the need for undesirable stoichiometric oxidants, independent synthesis of reactive intermediates, or the formation of wasteful byproducts. These strategies include electrochemical [7][8][9][10] and aerobic oxidative coupling methods.…”

“…Catalytic methods for oxidative N–N bond formation are the focus of increasing attention and have applications ranging from chemical synthesis 1 to energy conversion ( e.g. , ammonia fuel cells).…”

An Effective Method for the Synthesis of 1,3‐Dihydro‐2H‐indazoles via N‐N Bond Formation

“…In consideration of these activities, a variety of methods have been developed to synthesize indazole derivatives. The N−N bond formation is critical but very challenging strategy that has attracted much attention . Indeed, until now, a large number of nitrogen‐nitrogen bond formation methods have been developed.…”

“…[1] In consideration of these activities, a variety of methods have been developed to synthesize indazole derivatives. [2] Indeed, until now, a large number of nitrogen-nitrogen bond formation methods have been developed. [2] Indeed, until now, a large number of nitrogen-nitrogen bond formation methods have been developed.…”

“…The NÀ N bond formation is critical but very challenging strategy that has attracted much attention. [2] Indeed, until now, a large number of nitrogen-nitrogen bond formation methods have been developed. For example, Cu(OAc) 2 could be used as a catalyst to promote the cleavage of CÀ H bonds, and the following NÀ N bond is formed to give 1,2,3-triazoles.…”