US4278809A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing 2-isocyanatoalkyl esters of organic carboxylic acids
Assignee: Dow Chemical Co
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Filing: 1977-06-15
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Granted: 1981-07-14
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Expires: 1997-06-15
Abstract
Abstract 2-Isocyanatoalkyl esters of organic carboxylic acids are prepared by reacting (a) an aqueous solution of a 2-oxazoline with (b) an organic solution of phosgene dissolved in a water-immiscible organic solvent in the presence of (c) a hydrochloric acid acceptor. As an example, 2-isocyanatoethyl methacrylate was prepared by concurrently blending an aqueous stream of 2-isopropenyl-2-oxazoline, a methylene chloride stream of phosgene and an aqueous stream of sodium hydroxide at a temperature of from about 0° C. to about 10° C. The reaction rate is very high and the reaction is essentially complete upon blending the reactants.
Inventors
- 👤 Kenneth A. Burdett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:34
CPC Classifications
C; C07; C07C; C07C263/00; C07C263/08; C07D; C07D263/00; C07D263/02; C07D263/08; C07D263/10; C07D263/12; C07D263/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
63 words
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting (a) an aqueous solution of a 2-oxazoline, and (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of (c) a hydrochloric acid acceptor, wherein (a), (b), and (c) are added essentially simultaneously to a reaction vessel with efficient blending in essentially stoichometric amounts.
Claim 2
Dependent Claim
63 words
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting (a) an aqueous solution of a 2-oxazoline, and (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of (c) a hydrochloric acid acceptor, wherein (a), (b), and (c) are added essentially simultaneously to a reaction vessel with efficient blending in essentially stoichometric amounts.
Claim 3
Dependent Claim
45 words
The process defined by claim 1 wherein (a) is an aqueous solution of 2-vinyl- or 2-isopropenyl-2-oxazoline, (b) is a methylene chloride solution of phosgene, (c) is an aqueous solution of sodium hydroxide, and wherein the reaction temperature is from about -10° C. to 15° C.
Claim 4
Dependent Claim
125 words
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting (a) an aqueous solution of a 2-oxazoline, and (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of (c) a hydrochloric acid acceptor, wherein said process is conducted by simultaneously introducing a precooled aqueous solution of said 2-oxazoline, a precooled organic solution of phosgene, and a precooled aqueous solution of the hydrochloric acid acceptor into a reaction vessel with vigorous stirring and cooling; water being present in said reaction mixture in an amount sufficient to satisfy stoichiometry of the reaction and to provide a liquid aqueous phase in the reaction mixture and said reaction temperature being maintained between about -30° C. and about 25° C.
Claim 5
Dependent Claim
125 words
A process for preparing a 2-isocyanatoalkyl ester of an organic carboxylic acid comprising reacting by contacting (a) an aqueous solution of a 2-oxazoline, and (b) a solution of phosgene in a water-immiscible organic solvent, in the presence of (c) a hydrochloric acid acceptor, wherein said process is conducted by simultaneously introducing a precooled aqueous solution of said 2-oxazoline, a precooled organic solution of phosgene, and a precooled aqueous solution of the hydrochloric acid acceptor into a reaction vessel with vigorous stirring and cooling; water being present in said reaction mixture in an amount sufficient to satisfy stoichiometry of the reaction and to provide a liquid aqueous phase in the reaction mixture and said reaction temperature being maintained between about -30° C. and about 25° C.
Claim 6
Dependent Claim
44 words
The process defined by claim 3 wherein (a) is an aqueous solution of 2-isopropenyl-2-oxazoline, (b) is a methylene chloride solution of phosgene, (c) is an aqueous solution of sodium hydroxide and said reaction temperature is maintained from about -10° C. to about 15° C.
References Cited (Backward Citations)
US3535332A
Cited
GB1252099A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-07-13 | 1985-01-12 | 1985-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-13 | 1989-01-12 | 1989-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-13 | 1993-01-12 | 1993-07-14 | $7700.00 | Window Closed / Lapsed |