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2-Methoxy-4-methyl-3-oxo-cyclopent-1-ene-1,4-dicarboxylic acid esters

Assignee: El Paso Products Co
•
Filing: 1975-05-12
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Granted: 1977-02-08
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Expires: 1995-05-12
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Abstract

Abstract The disclosure relates to a novel process for the preparation of 3-alkyl-cyclopentane-1,2-diones and, in particular, to a novel process for the preparation of 3-methyl-cyclopentane-1,2-dione also known as Maple Lactone. The process comprises condensation of esters of glutaric acid and oxalic acid in a polar aprotic solvent in the presence of an alkali metal alkoxide to form 3,5-dicarboalkoxy-cyclopentane-1,2-dione dialkali metal salts, alkylating said salts with an alkylating agent to form a 2-alkoxy-3,5-dicarboalkoxy-5-alkyl-cyclopent-1-ene removing said solvent therefrom, and hydrolyzing the remainder with a mineral acid to form a 3-alkyl-cyclopentane-1,2-dione.

Inventors

  • 👤 Thurman Chestler McFearin, Jr.

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 12:26
CPC Classifications
C; C07; C07C; C07C49/00; C07C49/587; C07C49/703; C07C49/707; C07C45/00; C07C45/51; C07C45/511; C07C45/513; C07C49/385; C07C49/395

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 6 words
As a composition of matter 2-methoxy-3,5-dicarboalkoxy-5-methylcyclopent-2-ene-1-one.
Claim 2
Dependent Claim 6 words
As a composition of matter 2-methoxy-3,5-dicarboalkoxy-5-methylcyclopent-2-ene-1-one.

References Cited (Backward Citations)

US2865962A Cited
US3870711A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-02-08 1980-08-09 1981-02-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-02-08 1984-08-09 1985-02-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-02-08 1988-08-09 1989-02-08 $7700.00 Window Closed / Lapsed

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