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Patent US4190583A successfully refreshed from Google Patents.
US4190583A
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US
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Process for the preparation of 3,4-methylenedioxymandelic acid
Assignee: Haarmann and Reimer GmbH
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Filing: 1978-11-29
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Granted: 1980-02-26
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Expires: 1998-11-29
Abstract
Abstract Process for the preparation of 3,4-methylenedioxymandelic acid, wherein glyoxylic acid is reacted with 1,2-methylenedioxybenzene in a strongly acid medium.
Inventors
- 👤 Kurt Bauer
- 👤 Reiner Molleken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:21
CPC Classifications
C; C07; C07D; C07D317/00; C07D317/08; C07D317/44; C07D317/46; C07D317/48; C07D317/50; C07D317/60
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
33 words
A process for the preparation of 3,4-methylenedioxymandelic acid, which comprises reacting glyoxylic acid with 1,2-methylenedioxybenzene in the presence of a strong acid having a dissociation constant in water of over 4.74×10 -4 .
Claim 2
Dependent Claim
33 words
A process for the preparation of 3,4-methylenedioxymandelic acid, which comprises reacting glyoxylic acid with 1,2-methylenedioxybenzene in the presence of a strong acid having a dissociation constant in water of over 4.74×10 -4 .
Claim 3
Dependent Claim
31 words
A process as claimed in claim 1, wherein the reaction is carried out in the presence of phosphoric acid, sulphuric acid, gaseous or concentrated hydrochloric acid, trifluoroacetic acid or dichloroacetic acid.
References Cited (Backward Citations)
US3970703A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-02-25 | 1983-08-27 | 1984-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-25 | 1987-08-27 | 1988-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-25 | 1991-08-27 | 1992-02-26 | $7700.00 | Window Closed / Lapsed |