Patent US4010182A successfully refreshed from Google Patents.
US4010182A
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US
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Method for producing N-(4-fluorophenyl)-2,3,-dichloromaleimide
Assignee: Mitsubishi Chemical Corp
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Filing: 1975-05-07
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Granted: 1977-03-01
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Expires: 1995-05-07
Abstract
Abstract N-(4-fluorophenyl)-2,3-dichloromaleimide of uniform grain size is produced either by reacting 2,3-dichloromaleic acid, an anhydride or an ester thereof with 4-fluoroaniline in an aqueous medium or by dehydrative-cyclization of either N-(4-fluorophenyl)-2,3-dichloromaleamic acid or 4-fluoroanilinium 2,3-dichloromaleate in an aqueous medium. The N-(4-fluorophenyl)-2,3-dichloromaleimide of uniform grain size provides improved fungicidal activity and is convenient for preparing an agricultural fungicidal composition.
Inventors
- 👤 Kazuo Matsui
- 👤 Taichiro Shigematsu
- 👤 Tetsuya Shibahara
- 👤 Makoto Nakazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:48
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/02; C07D207/44; C07D207/444; C07D207/456
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
53 words
In a process for the preparation of N-(4-fluorophenyl)-2,3-dichloromaleimide by reaction of a first reactant selected from the group consisting of 2,3-dichloromaleic acid, 2,3-dichloromaleic anhydride and esters of 2,3-dichloromaleic acid with 4-fluoroaniline as a second reactant or by dehydrative-cyclization reaction of N-(4-fluorophenyl)-2,3-dichloromaleamic acid or 4-fluoroanilinium-2,3-dichloromaleate, the improvement characterized by conducting the reaction in water.
Claim 2
Dependent Claim
53 words
In a process for the preparation of N-(4-fluorophenyl)-2,3-dichloromaleimide by reaction of a first reactant selected from the group consisting of 2,3-dichloromaleic acid, 2,3-dichloromaleic anhydride and esters of 2,3-dichloromaleic acid with 4-fluoroaniline as a second reactant or by dehydrative-cyclization reaction of N-(4-fluorophenyl)-2,3-dichloromaleamic acid or 4-fluoroanilinium-2,3-dichloromaleate, the improvement characterized by conducting the reaction in water.
Claim 3
Dependent Claim
35 words
The process of claim 1 wherein the amount of said water is 2 to 20 times by weight based on the weight of 4-fluoroaniline and the N-(4-fluorophenyl)-2,3-dichloromaleimide is prepared from said first and second reactants.
Claim 4
Dependent Claim
34 words
The process of claim 1 wherein the amount of said water is 2 to 20 times the weight of the reactants and the N-(4-fluorophenyl)-2,3-dichloromaleimide is prepared by dehydrative-cyclization of N-(4-fluorophenyl)-2,3-dichloromaleamic acid or 4-fluoroanilinium 2,3-dichloromaleate.
Claim 5
Dependent Claim
24 words
The process of claim 2 wherein said reaction is carried out by reacting said first reactant with 4-fluoroaniline in a mole ratio of 1.3:1.
Claim 6
Dependent Claim
29 words
The process of claim 1 wherein said reaction is conducted in two stages at different temperatures and wherein the N-(4-fluorophenyl)-2,3-dichloromaleimide is prepared by reacting said first reactant with 4-fluoroaniline.
Claim 7
Dependent Claim
51 words
The process of claim 5 wherein the first stage of said reaction is carried out at a temperature in the range of from room temperature to 60° C and the second stage of said reaction is subsequently carried out at a temperature in the range of 60° C to reflux temperature.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-29 | 1980-08-30 | 1981-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-29 | 1984-08-30 | 1985-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-29 | 1988-08-30 | 1989-03-01 | $7700.00 | Window Closed / Lapsed |