Acetamide → (1-Aminoethylidene)bisphosphonic acid

Reaction equation

[C:1]([NH2:4])(=O)[CH3:2].[P:5]([OH:8])([OH:7])[OH:6].Cl>>[NH2:4][C:1]([P:5]([OH:8])(=[O:6])[OH:7])([P:5]([OH:8])(=[O:7])[OH:6])[CH3:2]

Participants

Reactant 3

HCID 178Acetamide

HCID 313Hydrochloric Acid

HCID 107909Phosphorous acid

Product 1

HCID 84770(1-Aminoethylidene)bisphosphonic acid

Procedure

Into a mixture of 59 gm of acetamide and 82 gm of phosphorous acid, hydrogen chloride gas was introduced therein for a period of 3 hours. During this time the mixture was stirred and the temperature was maintained at 145° - 155° C. By further processing of the reaction mixture, analogously to Example 1, the 1-aminoethane-1,1 -diphosphonic acid was isolated and purified. The yield was 19.2 gm.