Title:
METHOD FOR PREPARING 1-ALKYL-PYRAZOL-5-CARBOXYLIC ACID ESTERS
Document Type and Number:
WIPO Patent Application WO2000001673
Kind Code:
A3
Abstract:
The present invention relates to a method for preparing 1-alkyl-pyrazol-5-carboxylic acid esters, wherein said method involves reacting the enolate of a 2,4-diketocarboxylic acid ester with a salt of N-alkylhydrazinium in the presence of water and a solvent. This method can be used for readily preparing 1-alkyl-pyrazol-5-carboxylic acid esters at a low cost, while minimising the formation of unwanted isomers.
Inventors:
MUELLER NIKOLAUS (DE)
MATZKE MICHAEL (DE)
MATZKE MICHAEL (DE)
Application Number:
PCT/EP1999/004297
Publication Date:
September 26, 2002
Filing Date:
June 21, 1999
Export Citation:
Assignee:
BAYER AG (DE)
MUELLER NIKOLAUS (DE)
MATZKE MICHAEL (DE)
MUELLER NIKOLAUS (DE)
MATZKE MICHAEL (DE)
International Classes:
C07D231/00; C07D231/14; (IPC1-7): C07D231/14
Foreign References:
| EP0854142A1 | 1998-07-22 |
Other References:
THEILHEIMER W: "SYNTHETIC METHODS OF ORGANIC CHEMISTRY, PASSAGE", SYNTHETIC METHODS OF ORGANIC CHEMISTRY, vol. 2, 1975, THEILHEIMER W, pages 128, XP002058628
THEILHEIMER W: "SYNTHETIC METHODS OF ORGANIC CHEMISTRY", SYNTHETIC METHODS OF ORGANIC CHEMISTRY, vol. 6, 1952, THEILHEIMER W, pages 148, XP002058629
DATABASE WPI Section Ch Week 198615, Derwent World Patents Index; Class B03, AN 1986-096631, XP002121094
DATABASE WPI Section Ch Week 199531, Derwent World Patents Index; Class B03, AN 1995-234200, XP002121095
THEILHEIMER W: "SYNTHETIC METHODS OF ORGANIC CHEMISTRY. "PASSAGE TEXT"", SYNTHETIC METHODS OF ORGANIC CHEMISTRY, vol. 16, 1962, THEILHEIMER W, pages 204, XP002058626
THEILHEIMER W: "SYNTHETIC METHODS OF ORGANIC CHEMISTRY", SYNTHETIC METHODS OF ORGANIC CHEMISTRY, vol. 6, 1952, THEILHEIMER W, pages 148, XP002058629
DATABASE WPI Section Ch Week 198615, Derwent World Patents Index; Class B03, AN 1986-096631, XP002121094
DATABASE WPI Section Ch Week 199531, Derwent World Patents Index; Class B03, AN 1995-234200, XP002121095
THEILHEIMER W: "SYNTHETIC METHODS OF ORGANIC CHEMISTRY. "PASSAGE TEXT"", SYNTHETIC METHODS OF ORGANIC CHEMISTRY, vol. 16, 1962, THEILHEIMER W, pages 204, XP002058626
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