Organic Letters
Letter
paper is particularly supported by “Aim for the Top University
Plan” of the National Chiao Tung University.
Scheme 5. Synthesis of Benzothiadiazine-Fused
Isocoumarins 23 and Naphthalene 24
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In conclusion, we have discovered a novel one-pot, two-step
domino reaction for the scaffold-fused synthesis of benzimida-
zothiadiazine dioxides. This is the first report of the synthesis of
unique regioisomers through the [3 + 3] approach where the
influence of reaction conditions on the regioselective formation
of a product is addressed. This challenge has been achieved
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ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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S
Spectroscopic data (1H and 13C NMR, HRMS) of
essential representative intermediates 12−19 and final
compounds 8a−j, 10a−j, 21a−n, 22a,b, 23a−j, and 24a
AUTHOR INFORMATION
Corresponding Author
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Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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We thank the Ministry of Science and Technology, Taiwan, for
financial assistance and the authorities of the National Chiao
Tung University for providing the laboratory facilities. This
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