Process for producing carboxy-alkane-aminoalkane diphosphonic acids and carboxy-alkane-aminoaryl- alkane diphosphonic acids
CA 1113475 A · Owner: Benckiser-Knapsack G.M.B.H. · Inventors: Walter, Edgar; Sommer, Klaus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides a process for producing carboxy-alkane-aminoalkane diphosphonic acids and carboxy-alkaneaminoaryl-alkane diphosphonic acids having the general formula wherein R1 is H, CH3, C2H5, C6H5, C6H11 or HOOC CmH2m where m is 2 to 5, R2 is H, CH3, C2H5, C6H5, CH2COOH or C2H4COOH R3, is H, CH3, C2H5, -CH2C6H5, -C2H4SCH3 -CH2COOH, -C2H4COOH, or, R2+R3 is , or R1+R2 is CmH2mCO where m is 2-5 and n, is 1-4, which comprises reacting an acyl-aminocarboxylic acid or an anhydride thereof having the general formula wherein R1, R2, n and R3 have the meaning as above with pyro-, phosphorous acid or phosphorous acid and phosphorus trichloride in the molar ratio of 5:1 to 1:2 at …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted December 1, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 1, 1998.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.