M. Lurdes S. Cristiano, Amadeu F. Brigas, Robert A. W. Johnstone, Rui M. S. Loureiro and Paula C. A. Pena
3-Allyloxy-1,2-benzisothiazole 1,1-dioxides 4 isomerize thermally to give [3,3]- and [1,3]-products 5, 6 of sigmatropic shift, of which the former reacts further to give solely the [1,3]-isomer.