(1-amino-1-phosphonoethyl)phosphonic acid

Conditions: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 1 liter autoclave was charged with a mixture of acetonitrile (61.5 g, 1.5 moles), ISOPAR-M (300 g), and the wetting agents (7.5 g each). The mixture was pressurized with nitrogen and heated to 150° C. Melted phosphorous acid (246 g, 3.0 moles) was pumped into the reactor through 15 minutes. The reaction was continued for 3 hours, maintaining the temperature at 150° C. Water (300 g) was pumped in and the product was collected after cooling. Colorless crystals of 1-amino-1,1-diphosphono ethane was obtained as fine grains, 76% yield. maintaining the temperature at 150° C was collected after cooling

Conditions: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 1 liter autoclave was charged with a mixture of acetonitrile (61.5 g, 1.5 moles), ISOPAR-M (300 g), and the wetting agents (7.5 g each). The mixture was pressurized with nitrogen and heated to 150° C. Melted phosphorous acid (246 g, 3.0 moles) was pumped into the reactor through 15 minutes. The reaction was continued for 3 hours, maintaining the temperature at 150° C. Water (300 g) was pumped in and the product was collected after cooling. Colorless crystals of 1-amino-1,1-diphosphono ethane was obtained as fine grains, 76% yield. maintaining the temperature at 150° C was collected after cooling

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of acetonitrile (8.2 g, 0.2 mole), phosphorous acid (32.8 g, 0.4 mole), ISOPAR-M (20 g), and the above wetting agents (0.5 g each) was reacted for 3 hours at 150° C. The mixture was cooled to 80° C and water (50 g) was added. The colorless emulsion broke to give colorless granular 1-amino-1,1-diphosphono ethane, 29 g (71% yield), m.p. 270°-271° C (decomposition). the above wetting agents (0.5 g each) was reacted for 3 hours at 150° C

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 103 g. of 1-amino ethane-1,1-diphosphonic acid are suspended in 100 g. of a 30% formaldehyde solution. 85 cc. of phosphorus trichloride are added thereto drop by drop while stirring. After the addition is completed, the mixture is heated to boiling until a homogeneous mixture is formed. The water is removed by evaporation in a vacuum. The resulting phosphonic acid mixture is precipitated by the addition of acetone. N-phosphono methylene-1-amino ethane-1,1-diphosphonic acid is obtained in this manner. After the addition the mixture is heated is formed The water is removed by evaporation in a vacuum The resulting phosphonic acid mixture is precipitated by the addition of acetone

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 22.7 g. (0.1 mole) of the mono-sodium salt of 1-amino ethane-1,1-diphosphonic acid are boiled under reflux in 30.6 g. (0.3 moles) of acetic acid anhydride for about 30 minutes. A clear solution is obtained. On cooling, a viscous yellowish sirup is produced. The sirup can be diluted with water and the aqueous solution can be used directly. In order to recover the crystalline reaction product, the sirup is added with stirring to 40 cc. of glacial acetic acid and the resulting crystalline product is filtered off by suction. After drying, 20.3 g. of the mono-sodium salt of N-acetyl-1-amino ethane-1,1-diphosphonic acid, corresponding to 75.4 % of the theoretical yield, are obtained. under reflux in 30.6 g A clear solution is obtained On cooling a viscous yellowish sirup is produced In order to recover the crystalline reaction product the sirup is added of glacial acetic acid and the resulting crystalline product is filtered off by suction After drying

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 22.7 g. (0.1 mole) of the mono-sodium salt of 1-amino ethane-1,1-diphosphonic acid are boiled under reflux in 30.6 g. (0.3 moles) of acetic acid anhydride for about 30 minutes. A clear solution is obtained. On cooling, a viscous yellowish sirup is produced. The sirup can be diluted with water and the aqueous solution can be used directly. In order to recover the crystalline reaction product, the sirup is added with stirring to 40 cc. of glacial acetic acid and the resulting crystalline product is filtered off by suction. After drying, 20.3 g. of the mono-sodium salt of N-acetyl-1-amino ethane-1,1-diphosphonic acid, corresponding to 75.4 % of the theoretical yield, are obtained. under reflux in 30.6 g A clear solution is obtained On cooling a viscous yellowish sirup is produced In order to recover the crystalline reaction product the sirup is added of glacial acetic acid and the resulting crystalline product is filtered off by suction After drying

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 22.7 g. (0.1 mole) of the mono-sodium salt of 1-amino ethane-1,1-diphosphonic acid are boiled under reflux in 30.6 g. (0.3 moles) of acetic acid anhydride for about 30 minutes. A clear solution is obtained. On cooling, a viscous yellowish sirup is produced. The sirup can be diluted with water and the aqueous solution can be used directly. In order to recover the crystalline reaction product, the sirup is added with stirring to 40 cc. of glacial acetic acid and the resulting crystalline product is filtered off by suction. After drying, 20.3 g. of the mono-sodium salt of N-acetyl-1-amino ethane-1,1-diphosphonic acid, corresponding to 75.4 % of the theoretical yield, are obtained. under reflux in 30.6 g A clear solution is obtained On cooling a viscous yellowish sirup is produced In order to recover the crystalline reaction product the sirup is added of glacial acetic acid and the resulting crystalline product is filtered off by suction After drying

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 22.7 g. (0.1 mole) of the mono-sodium salt of 1-amino ethane-1,1-diphosphonic acid are boiled under reflux in 30.6 g. (0.3 moles) of acetic acid anhydride for about 30 minutes. A clear solution is obtained. On cooling, a viscous yellowish sirup is produced. The sirup can be diluted with water and the aqueous solution can be used directly. In order to recover the crystalline reaction product, the sirup is added with stirring to 40 cc. of glacial acetic acid and the resulting crystalline product is filtered off by suction. After drying, 20.3 g. of the mono-sodium salt of N-acetyl-1-amino ethane-1,1-diphosphonic acid, corresponding to 75.4 % of the theoretical yield, are obtained. under reflux in 30.6 g A clear solution is obtained On cooling a viscous yellowish sirup is produced In order to recover the crystalline reaction product the sirup is added of glacial acetic acid and the resulting crystalline product is filtered off by suction After drying

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. was introduced the temperature was maintained at 145° - 155° C

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. was introduced the temperature was maintained at 145° - 155° C

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a reactor like the above were charged 130.5 g phosphorous acid and 69 g Sulfolane-W (tetramethylene sulfone, Shell Chemical Co.). 31.2 g acetonitrile was introduced slowly for 11/2 hours at 140°-150° C. and the reactants were held for additional 81/2 hours at 153°-158° C. The 1-aminoethane-1, 1-diphosphonic acid produced was isolated from the reaction mixture in the manner described in Example 1. The yield was 75% of the theory on the acetonitrile employed. 2 hours at 153°-158° C

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a reactor similar to the above were charged 174 g phosphorous acid and 92 g propionic acid. 41.5 g acetonitrile was introduced slowly for 72 minutes at 135°-140° C. into the agitated mixture which was maintained for an additional 10 hours at that temperature. The 1-aminoethane-1, 1-diphosphonic acid produced was isolated from the reaction mixture in the same manner as described in Example 1. The yield was 85% of the theory calculated on the acetonitrile employed. was maintained for an additional 10 hours at that temperature