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US4609749A
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Method for the simultaneous preparation of carboxylic acid trimethylsilyl esters and silylated carboxylic acid amides
Assignee: Dynamit Nobel AG
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Filing: 1985-11-22
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Granted: 1986-09-02
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Expires: 2005-11-22
Abstract
Abstract Carboxylic acid trimethylsilyl esters (I) and trimethylsilyl carboxylic acid amides can be prepared simultaneously from the corresponding carboxylic acid anhydrides; the esters (I) and monocarboxylic acid trimethylsilyl amides are formed first and can then be recovered, or else the bis-trimethylsilyl carboxylic acid amides are formed by further transposition with trimethylchlorosilane in the presence of tertiary amines, and are separated from the carboxylic acid trimethylsilyl ester (I) and recovered.
Inventors
- 👤 Hans-Joachim Kotzsch
- 👤 Hans-Joachim Vahlensieck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:51
CPC Classifications
C; C07; C07F; C07F7/00; C07F7/02; C07F7/08; C07F7/18; C07F7/1896; C07F7/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
50 words
A method for the simultaneous preparation of carboxylic acid trimethylsilyl esters and trimethylsilyl carboxylic acid amides, comprising reacting a carboxylic acid anhydride of the formula (RCO) 2 O at 40° to 130° C., preferably at 50°-90° C., with hexamethyldisilazane to form carboxylic acid trimethylsilyl esters and mono-trimethylsilyl carboxylic acid amides.
Claim 2
Independent Claim
50 words
A method for the simultaneous preparation of carboxylic acid trimethylsilyl esters and trimethylsilyl carboxylic acid amides, comprising reacting a carboxylic acid anhydride of the formula (RCO) 2 O at 40° to 130° C., preferably at 50°-90° C., with hexamethyldisilazane to form carboxylic acid trimethylsilyl esters and mono-trimethylsilyl carboxylic acid amides.
Claim 3
Dependent Claim
53 words
The method of claim 1 further comprising additionally reacting one mole of trimethylchlorosilane for each mole of mono-trimethylsilyl carboxylic acid amide at 40° to 80° C. in the presence of one mole of tertiary amine for each mole of the acid amide, separating tertiary amine x HCl and working up the silyl derivatives.
Claim 4
Dependent Claim
25 words
The method according to claim 2, wherein the carboxylic acid trimethylsilyl ester is recovered after the reaction with hexamethyldisilazane and monotrimethylsilylcarboxylic acid amide is separated.
Claim 5
Dependent Claim
23 words
The method according to claim 3, wherein the monotrimethylsilyl carboxylic acid amide is reacted only with trimethylchlorosilane in the presence of tertiary amine.
Claim 6
Dependent Claim
23 words
The method according to claim 2, wherein the amine is released with ammonia from the separated tert.-amine x HCl and obtained by distillation.
Claim 7
Dependent Claim
23 words
The method according to claim 3, wherein the amine is released with ammonia from the separated tert.-amine x HCl and obtained by distillation.
Claim 8
Dependent Claim
23 words
The method according to claim 4, wherein the amine is released with ammonia from the separated tert.-amine x HCl and obtained by distillation.
Claim 9
Dependent Claim
46 words
The method according to claim 1, wherein R represents preferably CH 3 , C 2 H 5 , C 3 H 7 , CH(CH 3 ) 2 , CH 2 ═CH, CH 2 ═CCH 3 , CH 2 F, CHF 2 , or CF 3 .
Claim 10
Dependent Claim
46 words
The method according to claim 2, wherein R represents preferably CH 3 , C 2 H 5 , C 3 H 7 , CH(CH 3 ) 2 , CH 2 ═CH, CH 2 ═CCH 3 , CH 2 F, CHF 2 , or CF 3 .
Claim 11
Dependent Claim
16 words
The method of claim 9, wherein the tertiary amine is trimethylamine, triethylamine, tributylamine, N.N-dimethylaniline and pyridine.
References Cited (Backward Citations)
US3839387A
Cited
US4059559A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-01 | 1990-03-03 | 1990-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-01 | 1994-03-03 | 1994-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-01 | 1998-03-03 | 1998-09-02 | $7700.00 | Window Closed / Lapsed |