Organic Letters
Letter
(6) (a) Davies, P. W.; Cremonesi, A.; Dumitrescu, L. Angew. Chem.,
Int. Ed. 2011, 50, 8931. (b) Chatzopoulou, E.; Davies, P. W. Chem.
Commun. 2013, 46, 8617.
ASSOCIATED CONTENT
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S
* Supporting Information
(7) Examples of nucleophilic nitrenoids in gold-catalyzed intra-
molecular reactions: (a) Gorin, D. J.; Davis, N. R.; Toste, F. D. J. Am.
Chem. Soc. 2005, 127, 11260. (b) Hiroya, K.; Matsumoto, S.;
Ashikawa, M.; Ogiwara, K.; Sakamoto, T. Org. Lett. 2006, 8, 5349.
(c) Shapiro, N. D.; Toste, F. D. J. Am. Chem. Soc. 2007, 129, 4160.
(d) Huo, Z.; Yamamoto, Y. Tetrahedron Lett. 2009, 50, 3651.
(e) Wetzel, A.; Gagosz, F. Angew. Chem., Int. Ed. 2011, 50, 7354.
(f) Lu, B.; Luo, Y.; Liu, L.; Ye, L.; Wang, Y.; Zhang, L. Angew. Chem.,
Int. Ed. 2011, 50, 8358. (g) Xiao, Y.; Zhang, L. Org. Lett. 2012, 14,
4662. (h) Tokimizu, Y.; Oishi, S.; Fujii, N.; Ohno, H. Org. Lett. 2014,
16, 3138.
Survey of reaction conditions, experimental procedures and
characterization, spectral data for all new compounds, NOE
experiments for 3a, and the data for single-crystal X-ray
diffraction of 19 and 23 (CIF). This material is available free
AUTHOR INFORMATION
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Corresponding Author
Notes
(8) Intermolecular tosylnitrene addition to ynamides: Li, C.; Zhang,
L. Org. Lett. 2011, 13, 1738.
(9) (a) Burgos, C.; Delgado, F.; Garcia-Navio, J. L.; Izquierdo, M.
L.; Alvarez-Builla, J. Tetrahedron 1995, 31, 8649. (b) Reyes, M. J.;
Burgos, C.; Izquierdo, M. L.; Alvarez-Builla, J. Tetrahedron 2004, 60,
1093. (c) Cordoba, M.; Reyes, M. J.; Castillo, R.; Izquierdo, M. L.;
́
Alvarez-Builla, J. Tetrahedron 2008, 64, 1351.
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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The authors thank Dr. Louise Male (University of
Birmingham) for X-ray crystallography and Dr. Fernando
(10) Selected reviews of π-acid catalysis: (a) Hashmi, A. S. K. Chem.
Rev. 2007, 107, 3180. (b) Furstner, A.; Davies, P. W. Angew. Chem.,
̈
́
Sanchez-Cantalejo (University of Birmingham) and Joshua
Int. Ed. 2007, 46, 3410. (c) Lopez, F.; Mascarenas, J. L. Beilstein J.
́
̃
Priest (University of Birmingham) for the preparation of
ynamides 1e and 1(f,l,m) respectively. The University of
Birmingham is gratefully acknowledged for a studentship to
M.G. The facilities used in this research were part supported
through Birmingham Science City AM2 by Advantage West
Midlands and the European Regional Development Fund.
Org. Chem. 2011, 7, 1075. (d) Garayalde, D.; Nevado, C. ACS Catal.
2012, 2, 1462.
(11) A stepwise mechanism where pyridine is eliminated as a
distinct step prior to cyclization can be envisaged but is considered
less likely. See ref 6 and related mechanisms in: (a) Kramer, S.;
Skrydstrup, T. Angew. Chem., Int. Ed. 2012, 51, 4681. (b) Huang, X.;
Peng, B.; Luparia, M.; Gomes, L. F. R.; Veiros, L. F.; Maulide, N.
Angew. Chem., Int. Ed. 2012, 51, 8886.
REFERENCES
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(16) The regiochemistry of 3a was confirmed by NOE coupling; see
SI. Full characterization of the minor product has been hampered by
coelution with 3a though MS data confirm it to be an isomer.
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mmol, 609 mg) was run with a reduced catalyst loading (Au-2, 2 mol
%, 22.1 mg) giving 3q (0.99 g, 61%) after 6 h (see SI).
(20) CCDC 1018314 and 1018315 contain the supplementary
crystallographic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via www.
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