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:
May. 11, 1993
Filed:
Jan. 23, 1992
Hiroshi Goda, Kako, JP;
Nario Kimura, Kako, JP;
Naohiro Yoshikawa, Kako, JP;
Katsuhiko Yoshida, Kako, JP;
Sumitomo Seika Chemicals Co., Ltd., Hyogo, JP;
Abstract
The present invention is directed to novel 2,5-dichlorophenylthioglycolic acid derivative, a process for their production and a process for producing the desired product 2,5-dichlorophenylthioglycolic acid derived from said novel compounds. 2,5-dichlorophenylthioglycolic acid derivative of the present invention can be obtained by reacting 2,4,5-trichlorobenzensulfonates and thioglycolic acid in the presence of base, and said desired product can be obtained by desulfonating said compound in an aqueous solution of mineral acid. Novel 4-carboxymethylthio-2,5-dichlorobenzenesulfonates of the present invention can be used advantageously as an intermediate for the production of 2,5-dichlorophenylthioglycolic acid. The use of said intermediate makes it possible to obtain the desired product in a decreased process steps with high yield. In addition, it poses no problem of environmental pollution as pointed out with conventional methods because it uses no heavy metals.