Title:
PREPARATION OF SUBSTITUTED 2,3-DIFLUOROPYRIDINE
Document Type and Number:
Japanese Patent JP3425987
Kind Code:
B2
Abstract:
PURPOSE: To provide a new method for preparing 2,3-difluoropyridine which is especially important as starting material for producing plant protective agents or pharmaceuticals.
CONSTITUTION: The objective compound is prepared by allowing a substituted 2,3-halopyridine to react with a fluoride in the presence of a phase transfer catalyst preferably in a polar aprotic solvent, and then, without continuously removing the substituted 2,3-difluoropyridine thus obtained from the reaction mixture, purifying the product in the next stage. As the apparatus used for preparing the product is simple, the product is easily prepared. Though substituted 2,3-difluoropyridine is not continuously removed by the distillation, the product is obtained in sufficiently high yield and high space-time yield. Further, this process has such characteristic that the product can be prepared without use of a large quantity of pure cesium fluoride.
Inventors:
Ralph Puffilman
Theodor Papendhus
Theodor Papendhus
Application Number:
JP3065093A
Publication Date:
July 14, 2003
Filing Date:
February 19, 1993
Export Citation:
Assignee:
Clariant Gezershyaft Mito Besilyenktel Haftung
International Classes:
C07B61/00; C07D213/61; B01J31/24; (IPC1-7): C07D213/61; B01J31/24
Domestic Patent References:
| JP6143126A | ||||
| JP60156672A | ||||
| JP4164068A |
Attorney, Agent or Firm:
Mitsufumi Esaki (2 others)
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