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US3282985A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for producing dextro-trans-pyrethric acid

Assignee: Sumitomo Chemical Co Ltd
•
Filing: 1963-12-17
•
Granted: 1966-11-01
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Expires: 1983-12-17
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Abstract

No abstract record available.

Inventors

  • 👤 Matsui Masanao
  • 👤 Meguro Hiroshi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 13:44
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/43; C07C51/41; C07C51/412; C07C55/00; C07C55/02; C07C55/10; C07C55/14; C07C67/00; C07C67/08; C07B; C07B2200/00; C07B2200/07; C07C2601/00; C07C2601/02

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 89 words
A METHOD FOR PRODUCING DEXTRO-TRANS-PYRETHRIC ACID, WHICH COMPRISES HALF-SAPONIFYING DIMETHYL DEXTRO-TRANSCHRYSANTHEMUM DICRABOXYLATE WITH THE APPROXIMATELY EQUIMOLAR AMOUNT OF A MEMBER OF ALKALI METAL HYDROXIDE AND LOWER-ALCOHOLATE, TREATING THE MIXTURE OF THE MONOMETHYL ESTERS WITH THE APPROXIMATELY EQUIMOLAR AMOUNT OF QUININE TO FORM A MIXTURE OF THE SALTS THEREOF, SUBJECTING THE MIXTURE OF THE SALTS OF A FRACTIONAL CRYSTALLIZATION WITH AN ORGANIC SOLVENT TO SEPARATE THE QUININE SALT OF DEXTRO-TRANS-PYRETHRIC ACID FROM THAT OF DEXTRO-TRANS-B(2,2-DIMETHYL-3-METHOXY - CARBONYL - CYCLOPROPYL)METHACRYLIC ACID, AND HYDROLYZING THE SEPARATED SALT TO YIELD FREE DEXTRO-TRANS-PYRETHRIC ACID.
Claim 2
Independent Claim 89 words
A METHOD FOR PRODUCING DEXTRO-TRANS-PYRETHRIC ACID, WHICH COMPRISES HALF-SAPONIFYING DIMETHYL DEXTRO-TRANSCHRYSANTHEMUM DICRABOXYLATE WITH THE APPROXIMATELY EQUIMOLAR AMOUNT OF A MEMBER OF ALKALI METAL HYDROXIDE AND LOWER-ALCOHOLATE, TREATING THE MIXTURE OF THE MONOMETHYL ESTERS WITH THE APPROXIMATELY EQUIMOLAR AMOUNT OF QUININE TO FORM A MIXTURE OF THE SALTS THEREOF, SUBJECTING THE MIXTURE OF THE SALTS OF A FRACTIONAL CRYSTALLIZATION WITH AN ORGANIC SOLVENT TO SEPARATE THE QUININE SALT OF DEXTRO-TRANS-PYRETHRIC ACID FROM THAT OF DEXTRO-TRANS-B(2,2-DIMETHYL-3-METHOXY - CARBONYL - CYCLOPROPYL)METHACRYLIC ACID, AND HYDROLYZING THE SEPARATED SALT TO YIELD FREE DEXTRO-TRANS-PYRETHRIC ACID.

References Cited (Backward Citations)

US3009946A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-10-31 1970-05-02 1970-11-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-10-31 1974-05-02 1974-11-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-10-31 1978-05-02 1978-11-01 $7700.00 Window Closed / Lapsed

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