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:
Aug. 13, 1985
Filed:
Feb. 03, 1983
Charles J Guinosso, King of Prussia, PA (US);
American Home Products Corporation, New York, NY (US);
Abstract
Disclosed herein is a process for preparing indoline-2-carboxylic acids from the corresponding indole-2-carboxylic acid or ester in which the indole-2-carboxylic acid or ester is first reduced to the indoline-2-carboxylic acid ester tin complex using stannous chloride and dry hydrogen chloride gas in a lower alkanol solvent at atmospheric pressures; and the resulting tin complex, dissolved in a lower alkanol, is converted directly to the free indoline-2-carboxylic acid by treatment with aqueous potassium or sodium hydroxide. The aqueous hydroxide treatment may take place in situ or after first isolating the intermediate indoline-2-carboxylic acid ester tin complex.