The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 02, 1997
Filed:
Oct. 29, 1996
Yasuo Yamamoto, Niigata, JP;
Naoki Shirakawa, Niigata, JP;
Shinichi Takano, Niigata, JP;
Yoshio Kawai, Niigata, JP;
Japan Hydrazine Co., Ltd., Tokyo, JP;
Abstract
A process for the preparation of pyrazolone derivatives represented by the general formula ##STR1## wherein R is a hydrogen atom, an alkyl group, an allyl group, an aryl group or an aralkyl group, and R.sub.1 and R.sub.2 are, respectively, a hydrogen atom, an alkyl group or a phenyl group which may have a substituent, comprising reacting a 2,3-dihalocarboxylic acid derivative or a 2-haloacrylic acid derivative with a hydrazine derivative. A pyrazolone or 1-substituted-3-pyrazolones useful as intermediate starting materials for the synthesis of agricultural chemicals, medicine and chemical compounds can be easily and cheaply prepared from widely used industrial starting materials.