Novel synthesis of 3,3-substituted dihydrobenzisothiazole-1,1-dioxides and -2,3-dihydronaphtho-1,2-thiazine-1,1-dioxides
US4178447A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1977 |
| Grant date | Dec 11, 1979 |
| Priority date | — |
| Expiry date | Sep 23, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/55
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a method of synthesizing certain 3-(carbocyclic aryl)-3-(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) by reacting (a) a 4-OP-carbocyclic aryllithium compound wherein P is a protecting group and (b) a 3-(carbocyclic aryl)benz[d]isothiazole-1,1-dioxide wherein said 3-(carbocyclic aryl) moiety is other than a 3-(4'-OP-carbocyclic aryl) moiety to give (c) the corresponding 3-carbocyclic aryl)-3-(4'-OP-carbocyclic aryl)-2,3-dihydrobenz[d]isothiazole-1,1-dioxide. The -2,3-dihydronaphtho[1,8-de]-1,2-thiazine-1,1-dioxides are prepared in the same manner by reacting a 3-(carbocyclic aryl)naphtho[1,8-de]-1,2-thiazine-1,1-dioxide with said 4'-OP-carbocyclic aryllithium compound. In a further embodiment, the compounds synthesized according to the foregoing method are reacted with a carboxylic acid halide to give the corresponding 2-carbonyl-substituted 2,3-dihydrobenz[d]isothiazole-1,1-dioxide (or -2,3-dihydronaphtho[1,8-de]-1,2-thiazine-1,1-dioxides) followed by removing the protecting group, P, with weak acid to yield certain phenol and 1-naphthol sulfam(na)phthaleins useful, e.g., as …
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