Process for synthesis of azacycloalkane-2,2-diphosponic acids
March 10, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesAdducts of epoxy compounds and products of reaction of &3xb5;-caprolactam with N-alkylalkylenediamine and methods of preparation Azacycloalkane-2,2-diphosphonic acids Process of stabilization of anhydrous dibasic calcium phosphate against fluorine ions with azacycloalkane-2,2-diphosphonic acids Process of stabilization of dibasic calcium phosphate dihydrate against hydrolysis with azacycloalkane-2,2-diphosphonic acids Reaction products of epsilon-caprolactam with vicinal hydroxyalkylamines and alkoxylation products thereof Patent #: 4150024 InventorsAssigneeApplicationNo. 322328 filed on 03/10/1989US Classes:540/450, The hetero ring contains at least eight members including nitrogen and carbon540/542, Phosphorus attached directly or indirectly to the hetero ring by nonionic bonding546/21, Phosphorus attached directly to the six-membered hetero ring by nonionic bonding548/412, Phosphorus attached directly to the five-membered hetero ring by nonionic bonding987/91, Seven or more atoms in ring containing the single N atom (9/553A7)987/96, Hydrogenated pyridine ring (9/59; 9/59G; 9/59K; 9/59K2; 9/59K4; 9/59R)987/103Five-membered ring containing a single N atom (9/572; 9/572G; 9/572K; 9/572K2; 9/572K4; 9/572R)ExaminersPrimary: Shah, Mukund J.Assistant: Sohn, Miriam Attorney, Agent or FirmForeign Patent References
International ClassC07F 009/30Foreign Application Priority Data1989-03-11 DEAbstractA reaction medium of ethanol condensed with 1-20, most preferably 4-6 moles, of ethylene or propylene oxide per mole of ethanol greatly improves the practicality of the preparation of azacycloalkane-2,2-diphosphonic acids of the general formula I: ##STR1## where R means a hydrogen or a lower alkyl radical with from 1 to 3 carbon atoms, and n means an integer between 3 and 11, by phosphonylating the corresponding lactams with phosphonic acid and phosphorous trihalides in the presence of water.Field of SearchThe hetero ring contains at least eight members including nitrogen and carbonPhosphorus attached directly or indirectly to the hetero ring by nonionic bonding Phosphorus attached directly to the six-membered hetero ring by nonionic bonding Phosphorus attached directly to the five-membered hetero ring by nonionic bonding |
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