2,1-Benzisothiazoles spectra

Benzisothiazole is a very pale yellow solid, m.p. 37°, with an odor of bitter almonds. It is slightly soluble in water, volatile in steam, and very soluble in concentrated acids and in almost all organic solvents. It boils at 220° without appreciable decomposition.3 Few other physical properties or spectroscopic data appear to have been recorded, but the 60 MHz NMR spectrum of a solution in carbon tetrachloride shows a singlet at 8.735, ascribed to the proton on the heterocyclic ring, and a complex band between 7.12 and 8.008 resulting from the benzenoid ring protons.25... 

The proton NMR spectrum of 2,1-benzisothiazole has been analyzed109 and the parameters are listed in Table I. The variation in the chemical shift of H-3 has been reported for a number of mono-and disubstituted 2,1-benzisothiazoles 106,110 this H-3 proton is... 

In the mass spectrum, breakdown of 1,2-benzisothiazoles usually results in loss of HCN and CS fragments28 there is some evidence that the molecular ions from 1,2-benzisothiazole and from benzothiazole possess a common structure.29... 

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