A novel, green and efficient visible-light-promoted decarboxylative aminoalkylation reaction of imidazo[1,2-a]pyridines with N-aryl glycines has been described.

A novel and efficient direct oxidative phosphonylation of α-amino ketones and α-amino acid derivatives with dialkyl phosphites by the catalysis of a cobalt salt under air is disclosed. A variety of α-amino ketones and α-amino acid derivatives underwent the reaction well with dialkyl phosphites to produce the desired α-aminophosphonates. This protocol not only provides an alternative synthetic route for the preparation of diverse α-aminophosphonates but also avoids the use of potentially explosive peroxide agents.

A rapid and highly efficient copper(II)-catalyzed cross-dehydrogenative coupling (CDC) reaction of N-arylglycine esters with imidazo[1,2-a]pyridines has been described. A broad range of N-arylglycine esters underwent the CDC reaction smoothly with 2-arylimidazo[1,2-a]pyridines to give α-substituted α-amino acid esters in excellent yields. This synthetic method has the advantages of high yields, good functional groups compatibility, simple operation, and mild reaction conditions. A possible mechanism for the CDC reaction is also proposed. The use of a copper salt as the catalyst and air as the terminal oxidant makes this transformation sustainable and practical.