Diamidodiphosphoric Acid, (NH₂)₂P₂O₃(OH)₂

Diamidodiphosphoric Acid, (NH₂)₂P₂O₃(OH)₂, was prepared by the action of phosphoryl chloride at low temperatures on ammonia in the presence of some water, thus

2NH₃ + 2POCl₃ + 3H₂O = 6HCl + (NH₂)₂P₂O₃(OH)₂

It may also be obtained by several other reactions. The diammonium salt has been prepared in the crystalline state and various other salts as precipitates.