Synthesis of 2-phosphonylated imidazo[1,2-a]pyridines under catalyst-free conditions

A series of novel 2-phosphonylated imidazo[1,2-a]pyridines was accessed from CN coupling of chloroethynylphosphonates and commercially available N-unsubstituted 2-aminopyridines. The product yield depends on the nature and position of the substituent in the pyridine...