2, l-Benzisothiazol-3 -thiones

Isothiazoles are reported to yield the lactam (101) on reaction with diphenyl ketene <85BSB149>. Ethyne dicarboxylate esters add to 2,1-benzisothiazole to generate quinoline esters (102), and benzyne reacts to yield aeridine <83H(20)489, 88JCS(Pl)2l4l>. 2-Methyl-2,l-benzisothiazolin-3-thione with acetylene esters forms 2-iminobenzoquinone methides (103), which dimerize to give diazocines (104) or further react with the ethyne ester to yield diadducts (105). The initial adduct formed with phenylethyne and 2-methyl-2,l-benzisothiazolin-3-thione rearranges to produce l,2-dithiole[3,26]... 

A series of compounds with a 2,1-benzisothiazol-basis were easily available from 2, 1-benzisothiazol-3(2//)-one 180. The treatment of 1-methyl-2, l-benzisothiazol-3 (2//)-one 180 with phosphorus pentasulfide in pyridine gave the 1-methyl 2,1-benz-isothiazol-3(2//)-thione 181 in 28% yield. The preparation of l-methyl-3-methylthio-... 

The 1-methyl-2, l-benzisothiazol-3(2/7)-thiones 181 reacted with sodium /V-chloro-benzensulfonamide 186 to sulfimides 187, sulfinamidinates 188 and to sulfonamides 190 (20-78%). Sulfonamidates 189 were synthesized by an oxidation of sulfimides... 

Tables II-XI list 1,2-benzisothiazoles, Tables XII-XV 2,1-benzisothiazoles. There are a number of minor groups in these series which, because they appear in only a small number of references, are comparatively easy for the reader to locate, and so they are not tabulated here. These are 2-arylsulfonyl-64 and 2-arylideneamino-1,2-benzisothiazoles58 [(101) and (102), respectively], certain 2,1-benzisothiazole quaternary azo dyes (103),117 2,1-benzisothiazolin-3-ones (97)123 and -3-thiones (95),123,124 3,3 -bis-2,l-benzisothiazol-ylidenes (96),123 and 4,5,6,7-tetrahydro derivatives of types 93,122 99,12s. 27 and 100.125-127...

With the intention of comparing the biological activity of numerous 2-substituted l,2-benzisothiazol-3(277)-ones 88b and their sulfur analogues 88a <1985AHC105, 1994EJM743>, with that of the pyridine series and their derivatives, isothiazolo[5,4- ]pyridin-3(277)-ones 90b and isothiazolo[5,4-. ]pyridin-3(27/)-thiones 90a, the... 

Chloro- benzisothiazoles (153) or benzisothiazolium (154) salts react with thiolacetic acid to give 1,2-dithioles, and benzo-l,2-dithiole-3-thiones are formed from benzisothiazoline-3-thiones with hydrogen sulfide. An isothiazoline-3-thione (155) reacted with phenylethyne to form what may... 

Boberg et al. (96PS203) described the preparation of the sulfimides 162 and sulfonamides 163 from 2-methyl- or 2-benzyl-l,2-benzisothiazol-3(2//)-thiones 161 by reacting with sodium /V-clilorobenzensulfonamide (Scheme 55). Some sulfimides 162 decomposed at room temperature in the solid state, quickly in solution and especially in polar solvents. Their instability depends on the heterocyclic part of the molecule and also on the substituents in the aryl ring, e.g., electron withdrawing substituents like N02 or Cl stabilized sulfimides 162. 

A-Aryl 3-chloro-l,2-benzisothiazolium chlorides 109 were converted with thio-acetic acid to 3-aryl-imino-l,2-benzdithioles 332. In contrast, N-alkyl salts 109 reacted to form 2-alkyl-l,2-benzisothiazol-3(2//)-thiones 161, which are in equilibrium with 332 (67CB2435, Scheme 110). 

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