An efficient and eco-friendly protocol has been accomplished for a series of novel a-diaminophosphonates by a one-pot, three-component system via Kabachnik-Fields reaction of 4,40 -methylenedianiline, a variety of aryl/heteroaryl aldehydes and diphenylphosphite employing polyethylene glycol (PEG-400) as a green solvent at 80 C. All products were obtained in good to excellent yields (80–95%).