Organic Letters
Letter
shift for methylenes of succinimide moiety on addition of
ACKNOWLEDGMENTS
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MsOH in CDCl at room temperature (2.80 ppm to 2.86
3
We thank the Indian Institute of Technology Madras (Project
No. CHY/16-17/840/RFIR/ANBA) for financial support.
M.C. thanks CSIR, New Delhi, for a fellowship.
ppm). A similar shift was observed when the mixture was
heated to 50 °C. Likewise, a large downfield shift of carbonyl
1
3
carbon (176.5 ppm to 177.8 ppm) was seen in C NMR at
variable temperatures on addition of MsOH to 6a in CDCl3.
These observations reveal that the carbonyl oxygen of
succinimide moiety in 6a is possibly protonated on the
addition of MsOH, which makes the resultant species highly
electron deficient. As a consequence, protonated succinimide
moiety acts as the best leaving group, and the arylthio moiety is
transferred to substrate 4 as an electrophile.
REFERENCES
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2
(
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been successfully demonstrated employing N-(arylthio)-
succinimides as electrophilic arylthio source and methanesul-
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groups and synthesis of diverse arylthio tethered benzoxazines
in good yield with quick reaction time are the merit of the
present reaction. The developed method was also successfully
extended to the oxyselenation of o-vinylanilides in the absence
of acid promoter. Furthermore, preliminary variable-temper-
ature NMR experiments were also studied to reveal the possible
activation of the succinimide moiety with MsOH.
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ASSOCIATED CONTENT
Supporting Information
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Experimental details, characterization data, and H and
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C NMR spectra of isolated compounds (PDF)
AUTHOR INFORMATION
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ORCID
Notes
The authors declare no competing financial interest.
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Org. Lett. XXXX, XXX, XXX−XXX