L,2-Benzisothiazolin-3-one 1,1-dioxide,

Saccharin is the generic name for l,2-benzisothiazolin-3-one-1,1-dioxide and has been used for over 100 years, since its discovery by Fahlberg and Remsen in 1879 and the first production patent granted in 1885. Saccharin is a white crystalline product the sodium salt of saccharin is the commonly used form in the soft drinks industry. Solubility is excellent and stability under food and drink processing conditions is also excellent. 

Synthesis of l,2-Benzisothiazolin-3-one 1,1-Dioxides from 2-Aminobenzo-nitriles and SO - 2,6-02N(Me0)C6H3CN is reduced and the 2,6-NH2(MeO)CeH3CN is treated with NaN02 followed by SO2 to give 3-amino-... 

The interaction of heterocyclic hydroxy- and potential hydroxy-compounds with hexamethylphosphoric triamide (H MPA) at 220— 230 °C replaces the hydroxy- with a dimethylamino-group. The numerous examples include the conversion of saccharin into 3-dimethylaminobenzisothiazole 5 5 -dioxide. In the presence of pyrrolidine, the 3-(l -pyrrolidyl)-compound is obtained. Improved yields of iV-carboxymethyl-l,2-benzisothiazolin-3-one 1,1-dioxide have been obtained from sodium saccharin by the action of sodium bromoacetate, or chloroacetonitrile, followed by hydrolysis. ... 

Benzisothiazolin-3-one 1,1-dioxide benzoic sulfimide benzosulfimide l,2-dihydro-2-ketobenzisosulfonazole 2,3-dihydro-3-oxobenzisosulfonazole E954 Garantose gluside Hermesetas sacarina saccharin insoluble o-sulfobenzimide o-sulfobenzoic acid imide. 

A versatile synthetic approach to 4-hydroxy-1,2-benzothiazines was discovered by Abe and co-workers3-. 2-phenacyl-l,2-benzisothiazolin-3-ones (8 R = Ar) with strong base produce 3-benzoyl-4-hydroxy-2//-l,2-benzo-thiazine 1,1-dioxides (9 R = Ar) (Eq. 2). Yields up to 93% could be obtained using sodium ethoxide in ethanol. 

Synthesis of l,2-Benzisothiazolin-3-ones and their 1,1-Dioxides.-From 2-(Methylsulphinyl)benzamides and Thionyl Chloride. The reaction of 2-(methylsulphinyl)benzamides with thionyl chloride, a novel and convenient... 

Physical Properties of l,2-Benzisothiazolin-3-ones. - The infrared spectra of A -substituted isobenzothiazolinone 1,1-dioxides have been measured and characteristic frequencies for the S-N stretching vibration discussed. The medium bands at 819-870 cm are assigned to the S-N stretching. 

A general synthesis of 2-substituted l,2-benzisothiazolin-3-ones from 2-mer-captobenzoic acid involves esterification, halogenation to the sulphenyl halide, conversion into the sulphenamide, and cyclization with a strong base. The synthesis of 3-oxo-3/f-l,2-benzisothiazole 1-oxides by the action of hydrazoic acid on 2-sulphinylbenzoic acids has been extended (see Vol. 2, p. 579). 2-SuI-phinylbenzamides (48) react with hydrazoic acid in polyphosphoric acid to give 3-imino-3//-l,2-benzisothiazole 1-oxides (49) together with the related 5 functional derivatives of (49), and an unusual alkaline ring-scission to (50), were also described. ... 

AT-p-acetoxyphenyl", tetraacetate JV-acetyl-iV-p-bromophenyl-, 2,3,4,6-tetraaeetate N-(2-amino-3,4-dimethylphenyl)-, tetraacetate Af-(2-amino-4,5-dimethylphenyl)-, tetraacetate i f-(2-amino-4-methylphenyl)-, tetraacetate AT-o-aminophenyl-, 2,3,4,6-tetraacetate AT-(2-benzisothiazolin-3-one-l, 1-dioxide)-,... 

A number of sulfamoyl-substituted 3-acyl-4-hydroxy-l,2-benzothiazine 1,1-dioxides were prepared13 by base-catalyzed isomerization of sulfamoyl derivatives of benzisothiazolin-3-ones by essentially the method of Abe (Eq. 2). 

---