Organic Letters
Letter
(13) Smiles rearrangement of 15, leading to 25, was also found to be
a serious problem in the reaction. Addition of water as a cosolvent
effectively inhibited the Smiles rearrangement of 15. For details, see
the Supporting Information. For Smiles rearrangement of 2- or 4-
nitrobenzenesulfonamides, see: (a) Knipe, A. C.; Sridhar, N.;
Loughran, A. J. Chem. Soc., Chem. Commun. 1976, 630. (b) Yilmaz,
I.; Shine, H. J. J. Labelled Compd. Radiopharm. 2006, 25, 1157.
(c) Pizzirani, D.; Kaya, T.; Clemons, P. A.; Schreiber, S. L. Org. Lett.
2010, 12, 2822.
ASSOCIATED CONTENT
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S
* Supporting Information
Experimental details and spectroscopic data. This material is
AUTHOR INFORMATION
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Corresponding Authors
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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(14) Kramer, G.; Detert, H.; Meier, H. Heterocycles 2009, 78, 2201.
̈
This work was financially supported by JSPS KAKENHI Grant
Nos. 20002004, 25221301, Platform for Drug Discovery,
Informatics, and Structural Life Science (MEXT), the
Sumitomo Foundation, and the Tokyo Biochemical Research
Foundation.
(15) Another explanation for the regioselectivity involves a 1,2-
hydride shift of oxocarbenium ion 26, leading to N-sulfonyliminium
ion 27, deprotonation of which gives 17.
REFERENCES
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(16) Conformational searches were carried out using the Conflex
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epoxide with 9.
1
(17) The structure of the product was confirmed by H and 13C
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(7) Yamamoto and co-workers reported the synthesis of N-glycidyl-p-
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(10) The optical purity of 13 was >99% ee, which was confirmed by
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