Patent US4776831A successfully refreshed from Google Patents.
Patent US4400330A successfully refreshed from Google Patents.
US4400330A
Expired / Lapsed
US
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Method for preparation of N-phosphonomethylglycine
Assignee: Zeneca Inc
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Filing: 1982-07-29
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Granted: 1983-08-23
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Expires: 2002-07-29
Abstract
Abstract A method for the production of N-phosphonomethylglycine is disclosed which comprises the steps of: (1) first reacting 2,5-diketopiperazine with p-formaldehyde, then adding substituted phosphorus compound, all in the presence of a low molecular weight carboxylic acid solvent, to form an intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (2) isolating said intermediate compound, (3) subsequently reacting said intermediate bis-phosphonomethyl-2,5-diketopiperazine compound with a hydrolyzing agent; and, (4) thereafter acidifying said reactants with a mineral acid to form the end product, N-phosphonomethylglycine.
Inventors
- 👤 Rayman Y. Wong
- 👤 Nathan S. Bunker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:45
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/38; C07F9/44; C07F9/3804; C07F9/3808; C07F9/3813; C07F9/547; C07F9/645; C07F9/6509; C07F9/650952
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
112 words
A method for the production of N-phosphonomethylglycine which comprises the steps of: (1) first reacting 2,5-diketopiperazine with p-formaldehyde, then adding a substituted phosphorus compound, of the formula PXYZ, wherein X is a halogen, and Y and Z are independently selected from the group consisting of the halogens, all in the presence of a low molecular carboxylic acid solvent, to form an intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (2) isolating said intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (3) reacting said intermediate bis-phosphonomethyl-2,5-diketopiperazine compound with a hydrolyzing agent selected from an alkali or alkaline earth base to form a salt of N-phosphonomethylglycine, and (4) acidifying said salt with a suitable mineral acid to cause formation of the end product, N-phosphonomethylglycine.
Claim 2
Independent Claim
112 words
A method for the production of N-phosphonomethylglycine which comprises the steps of: (1) first reacting 2,5-diketopiperazine with p-formaldehyde, then adding a substituted phosphorus compound, of the formula PXYZ, wherein X is a halogen, and Y and Z are independently selected from the group consisting of the halogens, all in the presence of a low molecular carboxylic acid solvent, to form an intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (2) isolating said intermediate bis-phosphonomethyl-2,5-diketopiperazine compound, (3) reacting said intermediate bis-phosphonomethyl-2,5-diketopiperazine compound with a hydrolyzing agent selected from an alkali or alkaline earth base to form a salt of N-phosphonomethylglycine, and (4) acidifying said salt with a suitable mineral acid to cause formation of the end product, N-phosphonomethylglycine.
Claim 3
Dependent Claim
14 words
The method of claim 1 in which said substituted phosphorus compound is phosphorus trichloride.
Claim 4
Dependent Claim
16 words
The method of claim 1 in which said low molecular weight carboxylic acid is acetic acid.
Claim 5
Dependent Claim
16 words
The method of claim 1 in which the alkali or alkaline earth base is sodium hydroxide.
Claim 6
Dependent Claim
17 words
The method of claim 1 in which the reactants in step (4) are acidified with hydrochloric acid.
Claim 7
Dependent Claim
25 words
The method of claim 1 in which the reactants in step (1) are heated to a temperature ranging from about 25° to about 118° C.
Claim 8
Dependent Claim
27 words
The method of claim 1 in which the low molecular weight carboxylic acid is selected from the group consisting of acetic acid, propanoic acid, and butanoic acid.
Claim 9
Dependent Claim
24 words
The method of claim 2 in which the ratio of 2,5-diketopiperazine to p-formaldehyde to substituted phosphorus compound ranges from about 1:2:2 to about 1:1.2:1.2.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |