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:
Jan. 20, 1976
Filed:
Dec. 03, 1973
Applicant:
Inventor:
Yunn H Chiang, Woburn, MA (US);
Assignee:
Polaroid Corporation, Cambridge, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
2603 / ; 2603 / ; 2603 / ; 26032615 ; 96 2 / ;
Abstract
This invention is concerned with a novel class of protonated compounds, namely, 3-(indol-3-yl)dehydronaphthalide hydrochlorides, with their synthesis by the reaction of a 3-(indol-3-yl)naphthalide and a high-potential quinone in an inert anhydrous aprotic solvent in the presence of a carboxylic acid catalyst, and with the synthesis of indole naphthalide indicator dyes by reacting the said dehydronaphthalide hydrochlorides and an indole in an aromatic hydrocarbon solvent in the presence of a carboxylic acid catalyst.