in not given saponification of (NH2)PO(OC6H5)2 with KOH; formation of the free acid by react. of the formed acidic K salt with HClO4;;

in water addn. of 125 g (NH2)PO(OC6H5)2 in a hot soln. of 140 g KOH in 280 ml H2O; boiling for 5 min; pptn. of KHPO3(NH2) on cooling and acidification with 50 percent CH3CO2H; dissolving 13.5 g KHPO3(NH2) washed with alc. and ether in 125 ml ice-water; filtration;; addn. of 100 ml 10 percent HClO4 on cooling with ice; filtration of pptd. KClO4 by vac., addn. of 700 ml alc. to the filtrate; pptn. of (NH2)PO(OH)2 after a longer period of time; filtration by vac.; washing with ether and alc., drying; recrystn. from H2O;;

in further solvent(s) heating a suspension of PO(OH)2NH2 in tetrachlorethane with PCl4 on refluxing under exclusion of H2O for 4 h;; filtration of insol. products; continous removal of HCl with stream of dry air; expelling POCl3 and solvent at 90 °C and 14 Torr; solidification in high vac. at 55-58 °C;;

phosphoric acid hexamethyltriamide in water boiling;

in further solvent(s) heating a suspension of PO(OH)2NH2 in tetrachlorethane with PCl4 on refluxing under exclusion of H2O for 4 h;; filtration of insol. products; continous removal of HCl with stream of dry air; expelling POCl3 and solvent at 90 °C and 14 Torr; solidification in high vac. at 55-58 °C;;

in further solvent(s) heating a suspension of PO(OH)2NH2 in tetrachlorethane with PCl4 on refluxing under exclusion of H2O for 4 h;; filtration of insol. products; continous removal of HCl with stream of dry air; expelling POCl3 and solvent at 90 °C and 14 Torr; solidification in high vac. at 55-58 °C;;