US4547324A
Expired / Lapsed
US
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Method for preparation of N-phosphonomethylglycine
Assignee: Stauffer Chemical Co
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Filing: 1984-07-27
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Granted: 1985-10-15
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Expires: 2004-07-27
Abstract
Abstract A method for the production of N-phosphonomethylglycine which comprises reacting a 2-oxazolidone starting compound of the formula ##STR1## with p-formaldehyde, then adding a substituted phosphorus compound of the formula PXYZ wherein X is halogen, and Y and Z are independently selected from the group consisting of halogen, alkoxy having from 1-10 carbon atoms, and aryloxy, said reaction being conducted in the presence of a low molecular weight carboxylic acid solvent for the reactants, at a combination of time and temperature sufficient to cause the reaction to go to completion, and converting the 2-oxo-3-oxazolidinyl methyl phosphonic acid thus formed to N-phosphonomethylglycine.
Inventors
- 👤 Rayman Y. Wong
- 👤 Nathan S. Bunker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:09
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/547; C07F9/6527; C07F9/653; C07F9/28; C07F9/38; C07F9/3804; C07F9/3808; C07F9/3813
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
129 words
A method for the preparation of N-phosphonomethylglycine which comprises the steps of (1) reacting a starting compound of the formula ##STR3## with p-formaldehyde, then adding a substituted phosphorus compound of the formula PXYZ wherein X is halogen, and Y and Z are independently selected from the group consisting of halogen, alkoxy having from 1-10 carbon atoms and aryloxy, said reaction being conducted in the presence of a low molecular weight carboxylic acid solvent for the reactants, at a combination of time and temperature sufficient to cause the formation of an intermediate 2-oxo-3-oxazolidinyl methyl phosphonic acid, (2) reacting said 2-oxo-3-oxazolidinylmethyl phosphonic acid with an alkali or alkaline earth hydroxide, and cadmium oxide catalyst in water, and (3) subsequently acidifying the reactants with an acid to form the end product N-phosphonomethylglycine.
Claim 2
Independent Claim
129 words
A method for the preparation of N-phosphonomethylglycine which comprises the steps of (1) reacting a starting compound of the formula ##STR3## with p-formaldehyde, then adding a substituted phosphorus compound of the formula PXYZ wherein X is halogen, and Y and Z are independently selected from the group consisting of halogen, alkoxy having from 1-10 carbon atoms and aryloxy, said reaction being conducted in the presence of a low molecular weight carboxylic acid solvent for the reactants, at a combination of time and temperature sufficient to cause the formation of an intermediate 2-oxo-3-oxazolidinyl methyl phosphonic acid, (2) reacting said 2-oxo-3-oxazolidinylmethyl phosphonic acid with an alkali or alkaline earth hydroxide, and cadmium oxide catalyst in water, and (3) subsequently acidifying the reactants with an acid to form the end product N-phosphonomethylglycine.
Claim 3
Dependent Claim
25 words
The method of claim 1 in which the mole ratio of 2-oxazolidine to para-formaldehyde to substituted phosphorus compound ranges form about 1:1:1 to about 1:1.2:1.2.
Claim 4
Dependent Claim
15 words
The method of claim 1 in which the reaction is carried out at atmospheric pressure.
Claim 5
Dependent Claim
14 words
The method of claim 1 in which the phosphorus substituted compound is phosphorus trichloride.
References Cited (Backward Citations)
US4128558A
Cited
US4374131A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |