Reaction of N-(benzyloxycarbonyl)aminobenzylphosphonous acid with ethyl ort
hoformate afforded two major products diethyl N-(benzyloxycarbonyl)aminoben
zylphosphinite and ethyl (diethoxymethyl)[N-(benzyloxy-carbonyl)aminobenzyl
]phosphinate, a product of addition of phosphonous acid to orthoformate.