Synthesis of benzisothiazoles
Starting from readily available o-mercaptoacylphenones, a mild S-nitrosation and a subsequent intramolecular aza-Wittig reaction lead to the construction of 3-substituted benzisothiazoles.
N. O. Devarie-Baez, M. Xian, Org. Lett., 2010, 12, 752-754.
An acid-catalyzed thermolysis of a tert-butyl sulfoxide enables a simple synthesis of 3-substituted aryl[4,5]isothiazoles. Substituted aryl rings of varying electronic properties afford aryl[4,5]isothiazoles in high yields in the presence of a catalytic amount of p-toluenesulfonic acid in toluene.
H. Yuan, Z. Sun, Synlett, 2019, 30, 1904-1908.
tert-Butyl sulfoxides can be used as sulfinyl sources in an intramolecular sulfinylation of sulfonamides followed by an all-heteroatom Wittig-equivalent process to afford aryl[4,5]isothiazoles in high yields.
F. Xu, Y. Chen, E. Fan, Z. Sun, Org. Lett., 2016, 18, 2777-2779.