US4146724A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of isopropyl 4-methylimidazole-5-carboxylate
Assignee: BASF SE
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Filing: 1977-09-23
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Granted: 1979-03-27
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Expires: 1997-09-23
Abstract
Abstract The new isopropyl 4-methylimidazole-5-carboxylate and a new process for its manufacture by reacting isopropyl chloroacetoacetate with formamide and water in the presence of formic acid. Isopropyl 4-methylimidazole-5-carboxylate, manufactured by the process of the invention, is a starting material for the manufacture of dyes, pharmaceuticals and pesticides.
Inventors
- 👤 Albrecht Friederang
- 👤 Horst Koenig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:51
CPC Classifications
C; C07; C07D; C07D233/00; C07D233/54; C07D233/66; C07D233/90
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
76 words
A process for the manufacture of isopropyl 4-methylimidazole-5-carboxylate which comprises reacting at an elevated temperature of from 50° to 200° C. (a) isopropyl chloroacetoacetate with (b) water in an amount up to about 10 moles of water per mole of isopropyl chloroacetoacetate, and (c) a stoichiometric amount or an excess of formamide, in the presence of (d) formic acid in a ratio of from 0.5 to 10 moles of formic acid per mole of isopropyl chloroacetoacetate.
Claim 2
Dependent Claim
76 words
A process for the manufacture of isopropyl 4-methylimidazole-5-carboxylate which comprises reacting at an elevated temperature of from 50° to 200° C. (a) isopropyl chloroacetoacetate with (b) water in an amount up to about 10 moles of water per mole of isopropyl chloroacetoacetate, and (c) a stoichiometric amount or an excess of formamide, in the presence of (d) formic acid in a ratio of from 0.5 to 10 moles of formic acid per mole of isopropyl chloroacetoacetate.
Claim 3
Dependent Claim
29 words
A process as claimed in claim 1, wherein the reaction is carried out using a ratio of from 3 to 15 moles of formamide per mole of isopropyl chloroacetoacetate.
Claim 4
Dependent Claim
19 words
A process as claimed in claim 1, wherein the reaction is carried out at from 70° to 180° C.
Claim 5
Dependent Claim
19 words
A process as claimed in claim 1, wherein the reaction is carried out at from 100° to 170° C.
Claim 6
Dependent Claim
16 words
A process as claimed in claim 1, wherein the reaction is carried out without adding water.
Claim 7
Dependent Claim
26 words
A process as claimed in claim 1, wherein the reaction is carried out with from 0.5 to 10 moles of water per mole of isopropyl chloroacetoacetate.
Claim 8
Dependent Claim
26 words
A process as claimed in claim 1, wherein the reaction is carried out with from 0.5 to 1.9 moles of water per mole of isopropyl chloroacetoacetate.
Claim 9
Dependent Claim
26 words
A process as claimed in claim 1, wherein the reaction is carried out with from 1 to 1.55 moles of water per mole of isopropyl chloroacetoacetate.
Claim 10
Dependent Claim
57 words
A process as claimed in claim 1, wherein isopropyl chloroacetoacetate is first manufactured by reacting diketene and isopropenol, followed by chlorination, and the resulting reaction mixture from the chlorination is heated, dissolved reaction gases are removed under reduced pressure, formamide, water, formic acid and, if appropriate, an organic solvent are added, and the reaction is carried out.
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) | 1982-03-26 | 1982-09-25 | 1983-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-26 | 1986-09-25 | 1987-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-26 | 1990-09-25 | 1991-03-27 | $7700.00 | Window Closed / Lapsed |