N,N-Dialkylureidomethane diphosphonic acid and its preparation

摘要

Novel N,N'-dialkylureidomethane diphosphonic acids and their alkaline salts having the formula: <IMAGE> wherein R1 and R2 represent separate alkyl groups having 1 to 3 carbons or a ring forming alkylene group and R is hydrogen or an alkali metal; a novel method for their preparation comprising reacting formic acid with a corresponding N,N'-dialkylurea and phosphorus trichloride and the use of such compounds to prevent the formation of calcareous deposits in water systems.