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:
Jul. 31, 2001
Filed:
Jul. 11, 2000
Hisao Kondo, Kanagawa, JP;
Tetsuro Higashikawa, Tokyo, JP;
Medical Information Services, Inc., Tokyo, JP;
Abstract
The present invention is a process for producing 3-methyl-2-oxoindoline as defined by the following chemical formula (2), including heating of propionylphenylhydrazide as defined by the following chemical formula (1) in the presence of at least one kind of basic calcium compound, characterized in that an organic solvent withstanding at least at a temperature of 180° C. in the presence of the basic calcium compound is employed by at least an amount of equal weight to that of the propionylphenylhydrazide. With the construction mentioned above, even when the amount of calcium oxide is reduced down to as little as 15% of a conventionally used amount, at least 75% of a corresponding yield attained conventionally has been achieved. That is, not only control of the reaction and easy after treatment but also a high yield has been achieved;