The first synthesis of bicyclic ortho-quinodimethanes from tricyclic sulfone precursors has been achieved. The required sulfones, 3, 4, 5, 6-tetrahydro-1H-cyclohex [cd] benzothiophene-2, 2-dioxide and 1, 3, 4, 5, 6, 7-hexahydrocyclohept [cd] benzothiophene-2, 2-dioxide, were prepared from α-tetralone and benzosuberone utilizing a ring closure proceeding through a sulfonium salt intermediate. The same strategy failed when trying to ...
