Aromatic C- N bond formation

AROMATIC C—N BOND FORMATION WITH RELATED SUBSTRATES 378... 

Aromatic C-N Bond Formation with Non-Amine Substrates... 

The scope aromatic C-N bond formation extends beyond simple amine substrates. For example, selected imines, sulfoximines, hydrazines, lactams, azoles, and carbamates give useful products from intermolecular aromatic C-N bond formation. Intramolecular formation of aryl amides has been reported. In addition, allylamine undergoes arylation, providing a readily cleaved amine alternative to the ammonia surrogates benzylamine, t-butylcarbamate, or benzophenone imine. Although it is an amine substrate, the reaction of this reagent is included here because of its special purpose. 

Extensive efforts have been made to develop milder conditions for aromatic C—N bond formation with stoichiometric or catalytic amounts of copper. Efforts have also... 

Hartwig, J.F. Kawatsura, M. Hauck, S.I. Shaughnessy, K.H. Alcazar-Roman, L.M. Room-temperature palladium-catalyzed amination of aryl bromides and chlorides and extended scope of aromatic C-N bond formation with a commercial ligand. J. Org. Chem. 1999, 64, 5575. 

Several reports of late have described aromatic C-N bond formations using aryl boronic acids and copper catalysis. Initial reports from DuPont on this topic in the late 1990s relied on stoichiometric Cu(OAc)2, but more recently, it has been shown that reduced levels of copper (5-10%) can be used, together with myristic acid (10-20 mol%), forming diarylamines (Eqn. 1-5). ° Representative products, and yields, are shown below (32-35). 

Guo B, Zhang Q, Li G, Yao J, Hu C (2012) Aromatic C-N bond formation via simultaneous activation of C-H and N-H bonds direct oxyamination of benzene to aniline. Green Chem 14 1880-1883... 

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