反应详情

Diethyl p-aminobenzylphosphonate (1) (Aldrich Chemical Co., Milwaukee, WI) was converted to the p-carbobenzyloxy derivative (2) by the addition of 1.2 equivalents benzyl chloroformate in saturated aqueous sodium bicarbonate (NaHCO3) for 20 minutes at 23° C. That derivative was treated with 1.1 equivalents phosphorous pentachloride (PCl5) in chloroform at 50° C. for 2 hours. Pyridine (5 equivalents) and p-nitrophenol (3 equivalents) were added at 23° C. and subsequent workup provided the ethyl p-nitrophenyl phosphonate (3).