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Journal of the American Chemical Society
that the cyloaddition has to occur from an unsaturated nitrile oxide
AUTHOR INFORMATION
intermediate incorporating a Z-double bond, as indicated in Scheme 2.
(13) Halcomb, R. L.; Danishefsky, S. J. J. Am. Chem. Soc. 1989, 111,
6661.
(14) Uno, H.; Terakawa, T.; Suzuki, H. Chem. Lett. 1989, 1079.
(15) When the reaction was stopped at 50% conversion the product
could be isolated in 35% yield, or 70% brsm.
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Corresponding Author
Notes
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The authors declare no competing financial interests.
(16) (a) Petasis, N. A.; Bzowej, E. I. J. Am. Chem. Soc. 1990, 112, 6392.
(b) Martínez, I.; Howell, A. R. Tetrahedron Lett. 2000, 41, 5607.
(17) (a) Abelman, M. M.; Oh, T.; Overman, L. E. J. Org. Chem. 1987, 52,
4130. (b) Madin, A.; O’Donnell, C. J.; Oh, T.; Old, D. W.; Overman, L. E.;
Sharp, M. J. J. Am. Chem. Soc. 2005, 127, 18054.
(18) We speculated that the ether bridge adjacent to the reactive C(7)
carbon might be able to govern the stereoselective approach of the aryl
nucleophile through coordination to the arylpalladium intermediate. For
recent examples of ethers as directing groups in palladium catalyzed
reactions see: (a) Li, G.; Leow, D.; Wan, L.; Yu, J.-Q. Angew. Chem. Int.
Ed. 2013, 52, 1245. (b) Jamieson, A. G.; Sutherland, A. Org. Biomol.
Chem. 2005, 3, 735.
(19) (a) Furlán, R. L. E.; Mata, E. G.; Mascaretti, O. A. Tetrahedron Lett.
1996, 37, 5229. (b) Nicolaou, K. C.; Nevalainen, M.; Zak, M.; Bulat, S.;
Bella, M.; Safina, B. S. Angew. Chem. Int. Ed. 2003, 42, 3418.
(20) (a) Gupta, V. K.; Tandon, S. G. J. Indian. Chem. Soc. 1969, 46, 831.
(b) Smissman, E. E.; Corbett, M. D. J. Org. Chem. 1972, 37, 1947.
(21) Trost, B. M.; Thiel, O. R.; Tsui, H.-Ch. J. Am. Chem. Soc. 2003, 125,
13155.
ACKNOWLEDGMENT
9
We dedicate this manuscript to Prof. Dr. Scott E. Denmark in
honor of his 60th birthday. We are grateful to Dr. B. Schweizer
and M. Solar for X-ray crystallographic analysis, and to Dr. M.-O.
Ebert, R. Arnold, R. Frankenstein and P. Zumbrunnen for NMR
measurements. S.D. acknowledges the Stipendienfonds
Schweizerische Chemische Industrie (SSCI).
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