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US4156093A
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Process for increasing the production or recovery yields of hemiacetal-esters of glyoxylic acid
Assignee: Sanofi Aventis France
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Filing: 1978-03-13
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Granted: 1979-05-22
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Expires: 1998-03-13
Abstract
Abstract The process comprises the hot treatment at a temperature of 80° to 160° C. by an amount of 5 to 50% of 85% of phosphoric acid, of the residues resulting from the distillation of reaction media containing hemiacetal-esters under substantially anhydrous conditions. These reaction media are selected from among those resulting from the reaction of alcohols and glyoxylic acid and those resulting from the treatment of glyoxylic hemiacetal-esters with P 2 O 5 .
Inventors
- 👤 Yani Christidis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:31
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/30; C07C67/31
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
52 words
In a process for producing hemiacetal-esters by the reaction of glyoxylic acid with alcohols and distillation under substantially anhydrous conditions, the improvement comprising the hot treatment of the residue resulting from said distillation at a temperature of 80° to 160° C. with an amount of 5 to 50% of 85% phosphoric acid.
Claim 2
Dependent Claim
52 words
In a process for producing hemiacetal-esters by the reaction of glyoxylic acid with alcohols and distillation under substantially anhydrous conditions, the improvement comprising the hot treatment of the residue resulting from said distillation at a temperature of 80° to 160° C. with an amount of 5 to 50% of 85% phosphoric acid.
Claim 3
Dependent Claim
30 words
Process according to claim 1, wherein the amount of 85% phosphoric acid is in the range of 10 to 20% by weight with respect to the medium to be treated.
Claim 4
Dependent Claim
20 words
Process according to claim 1, wherein the hemiacetal-esters are those corresponding to alcohols of C 4 to C 12 .
References Cited (Backward Citations)
DE1004158B
Cited
US3911003A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |