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Published on: June 10, 2021
Isocoumarin Ring Rearrangement Approach to π-Extended Dibenzothiophenes
Hikaru Yanai1, Nayuna Ishizaka1, Teru Kawazoe1
1School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo192-0392, Japan.
Abstract:
Sulfur-functionalized isocoumarins have been successfully converted into 1,2,3,4-tetrasubstituted naphthalenes through the addition of ketene silyl acetals and the subsequent skeletal rearrangement triggered by fluoride. The densely and consecutively substituted structures of the resulting naphthalene products have enabled further ring closure between adjacent substituents on the aromatic scaffolds to give several π-extended dibenzothiophenes.
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