Highly efficient one-pot amination of carboxylate-substituted nitrogen-containing heteroaryl chlorides via Staudinger reaction

Abstract An efficient one-pot method for the synthesis of tert -butyl 6-aminonicotinate ( 5 ) is described. The key transformation involves displacement of the chloro group in tert -butyl 6-chloronicotinate ( 2 ) with azide followed by a Staudinger reaction. The scope of this methodology is further extended for the synthesis of a series of carboxylate-substituted heteroaryl amines. In particular, we synthesized tert -butyl carboxylate-substituted amino-pyridine, -pyridazine, and -pyrazine. In addition to one-pot conversion, short reaction time, simplicity of operation, ease of purification, and good yields are the key advantages of this methodology.