US3621042A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of methyl {11 -aminobenzenesulphonylcarbamate
Assignee: MAY F BAKER Ltd
•
Filing: 1970-03-19
•
Granted: 1971-11-16
•
Expires: 1990-03-19
Abstract
Abstract Methyl p-aminobenzenesulphonylcarbamate and its alkali metal and alkaline earth metal salts, which are useful as herbicides, are prepared by a new process which comprises reacting an alkali metal or alkaline earth metal salt of sulphanilamide with dimethyl carbonate in methanol at a temperature up to the boiling point of the reaction mixture. The free methyl paminobenzenesulphonylcarbamate can be obtained from the resulting alkali metal or alkaline earth metal salt of the sulphonylcarbamic ester by treatment with an acid.
Inventors
- 👤 Zdzislaw Jan Bujwid
- 👤 John Francis Hodgson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:50
CPC Classifications
A; A01; A01N; A01N47/00; A01N47/08; A01N47/10; A01N47/24
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
21 words
Process according to claim 1 in which the reaction is effected at a temperature of from 25* C. to 65* C.
Claim 2
Dependent Claim
16 words
Process according to claim 1 in which the reaction is effected at or near 65* C.
Claim 3
Dependent Claim
25 words
Process according to claim 1 in which 1 to 1.2 molar proportions of dimethyl carbonate are employed for each molar proportion of the sulphanilamide salt.
Claim 4
Dependent Claim
13 words
Process according to claim 1 in which M represents an alkali metal atom.
Claim 5
Dependent Claim
12 words
Process according to claim 5 in which M represents a sodium atom.
Claim 6
Dependent Claim
37 words
Process according to claim 1 in which the reaction is carried out in the presence of 0.05 to 0.15 moles of an alkali metal or alkaline earth metal hydride, alkoxide or amide, per mole of sulphanilamide salt.
Claim 7
Dependent Claim
34 words
Process according to claim 7 in which the reaction is carried out in the presence of 0.05 to 0.15 moles of an alkali metal or alkaline earth metal alkoxide per mole of sulphanilamide salt.
Claim 8
Dependent Claim
23 words
Process according to claim 7 in which the reaction is carried out in the presence of an alkali metal hydride, alkoxide or amide.
Claim 9
Dependent Claim
23 words
Process according to claim 9 in which the reaction is carried out in the presence of sodium hydride, a sodium alkoxide or sodamide.
Claim 10
Dependent Claim
18 words
Process according to claim 7 in which the reaction is carried out in the presence of sodium methoxide.
Claim 11
Dependent Claim
21 words
Process according to claim 1 for the preparation of methyl p-aminobenzenesulphonylcarbamate which comprises reacting a salt of sulphanilamide of the formula:
References Cited (Backward Citations)
DE122096C
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |