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:
Mar. 04, 1980
Filed:
Sep. 23, 1977
Stanley M Bloom, Waban, MA (US);
Alan L Borror, Lexington, MA (US);
James W Foley, Andover, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
This invention relates to certain 3,3-di(4'-OP-carbocyclic aryl)-2,3-dihydrobenz[d]isothiazole-1,1-dioxides (and-2,3-dihydronaphtho[1,8-de]-1,2-thiazine-1,1-dioxides) and to the preparation thereof by reacting (a) at least 2 equivalents of (i) a 4'-OP-carbocyclic aryllithium compound wherein P is a protecting group compatible with organometallic reagents or (ii) a 4'-OP-carbocyclic arylMgE compound wherein P is a protecting group compatible with organometallic reagents and E is chloro, bromo or iodo and (b) 1 equivalent of a compound selected from a 3-chlorobenz[d] isothiazole-1,1-dioxide and a 3-chloronaphtho[1,8-de]-1,2-thiazine-1,1-dioxide to give the corresponding 3,3-di(4'-OP-carbocyclic aryl)-2,3-dihydrobenz[d]isothiazole-1,1-dioxide or the corresponding 3,3-di(4'-OP-carbocyclic aryl)-2,3-dihydronaphtho[1,8-de]-1,2-thiazine-1,1-dioxide, which compounds are useful in the synthesis of phenol and 1-naphthol sulfam(na)-phthaleins employed, for example, as photographic optical filter agents and filter agent precursors.