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US4059559A
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Process for preparing N-triorganosilylcarbamide acid esters
Assignee: Wacker Chemie AG
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Filing: 1975-08-11
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Granted: 1977-11-22
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Expires: 1995-08-11
Abstract
Abstract An improved process for preparing N-triorganosilylcarbamide acid esters by reacting in the substantial absence of a solvent a carbamide acid ester having two hydrogen atoms linked to the nitrogen atom with a hexaorganodisilazane and a triorganohalosilane and thereafter separating the resultant N-triorganosilylcarbamide acid ester from ammonium halide.
Inventors
- 👤 Jurgen Burkhardt
- 👤 Paul Hittmair
- 👤 Karl-Heinrich Wegehaupt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:51
CPC Classifications
C; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
58 words
A process for preparing N-triorganosilylcarbamide acid esters which comprises reacting in the substantial absence of a solvent a carbamide acid ester having two hydrogen atoms linked to its nitrogen atom with a hexaorganodisilazane and a triorganohalosilane at a temperature of from 20° to 65° C. and thereafter separating the thus formed N-triorganosilylcarbamide acid ester from ammonium halide by-product.
Claim 2
Dependent Claim
58 words
A process for preparing N-triorganosilylcarbamide acid esters which comprises reacting in the substantial absence of a solvent a carbamide acid ester having two hydrogen atoms linked to its nitrogen atom with a hexaorganodisilazane and a triorganohalosilane at a temperature of from 20° to 65° C. and thereafter separating the thus formed N-triorganosilylcarbamide acid ester from ammonium halide by-product.
Claim 3
Dependent Claim
53 words
The process of claim 1 wherein the carbamide acid ester is represented by the general formula H.sub.2 NCOOR in which R is selected from the group consisting of hydrocarbon radicals having from 1 to 18 carbon atoms and substituted monovalent hydrocarbon radicals in which the substituted radicals are inert under the reaction conditions.
Claim 4
Dependent Claim
16 words
The process of claim 2 wherein the carbamide acid ester is a carbamide acid n-butyl ester.
Claim 5
Dependent Claim
58 words
The process of claim 1 wherein the hexaorganodisilazane is represented by the general formula (R.sub.3 Si).sub.2 NH in which R is selected from the group consisting of monovalent hydrocarbon radicals having from 1 to 18 carbon atoms except a tert. butyl radical and substituted monovalent hydrocarbon radicals in which the substituted radicals are inert under the reaction conditions.
Claim 6
Dependent Claim
10 words
The process of claim 4 wherein the hexaorganodisilazane is hexamethyldisilazane.
Claim 7
Dependent Claim
10 words
The process of claim 4 wherein the hexaorganodisilazane is divinyltetramethyldisilazane.
Claim 8
Dependent Claim
62 words
The process of claim 1 wherein the triorganohalosilane is represented by the general formula R.sub.3 SiX in which R is selected from the group consisting of monovalent hydrocarbon radicals having from 1 to 18 carbon atoms, except a tert.-butyl radical and substituted monovalent hydrocarbon radicals in which the substituted radicals are inert under the reaction conditions and X is a halogen atom.
Claim 9
Dependent Claim
10 words
The process of claim 7 wherein the triorganohalosilane is trimethylchlorosilane.
Claim 10
Dependent Claim
10 words
The process of claim 7 wherein the triorganohalosilane is vinyldimethylchlorosilane.
Claim 11
Dependent Claim
24 words
The process of claim 1 wherein the amount of solvent present is below 10 percent by weight based on the weight of the reactants.
Claim 12
Dependent Claim
15 words
The process of claim 1 wherein the hexaorganodisilazane is hexamethyldisilazane and the triorganohalosilane is trimethylchlorosilane.
Claim 13
Dependent Claim
10 words
The process of claim 11 wherein the hexaorganodisilazane is divinyltetramethyldisilazane.
References Cited (Backward Citations)
US2876209A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-21 | 1981-05-23 | 1981-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-21 | 1985-05-23 | 1985-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-21 | 1989-05-23 | 1989-11-22 | $7700.00 | Window Closed / Lapsed |