Abstract
Hitherto unreported 3-(aryloxyacetyl)-2,3-dihydrothieno[3,2-c][1]benzothiopyran-4-ones (4a-f) were synthesized in excellent yield by the application of the tandem [2,3] and [3,3] sigmatropic rearrangements of the 4-(4 -aryloxybut-2-ynylthio)[1]benzothiopyran-2-ones (3a-f). The substrates (3a-f) were synthesized by phase transfer catalyzed alkylation of previously unreported 4-mercaptothiopyran-2-ones with different 1-aryloxy-4-chlorobut-2-ynes.
Keywords: sigmatropic rearrangement, 4-mercaptothiopyran-2-ones, (aryloxyacetyl), dihydrothieno [3,2-c ] [1 ]benzothiopyran-4-ones