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2
(
ASSOCIATED CONTENT
Supporting Information
■
*
S
M.; Nachtsheim, B. J.; Ieawsuwan, W.; Atodiresei, I. Angew. Chem., Int.
Ed. 2011, 50, 6706. (b) Terada, M. Synthesis 2010, 1929. (c) Kampen,
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Experimental procedures, compound characterization, NMR
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(
d) Terada, M. Chem. Commun. 2008, 4097. (e) Akiyama, T. Chem.
Rev. 2007, 107, 5744.
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AUTHOR INFORMATION
(
12) Cooperative effects between carboxylic acids and phosphoric
Notes
acids in organocatalysis have been described (a) Monaco, M. R.;
Poladura, B.; Diaz de Los Bernardos, M.; Leutzsch, M.; Goddard, R.;
List, B. Angew. Chem., Int. Ed. 2014, 53, 7063. (b) Li, G.; Antilla, J. C.
Org. Lett. 2009, 11, 1075. (c) Rueping, M.; Azap, C. Angew. Chem., Int.
Ed. 2006, 45, 7832. (d) Akiyama, T.; Tamura, Y.; Itoh, J.; Morita, H.;
Fuchibe, K. Synlett 2006, 141. (e) Rueping, M.; Sugiono, E.; Schoepke,
F. R. Synlett 2007, 1441.
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
Generous support by the Max-Planck-Society and the European
Research Council (Advanced Grant “High Performance Lewis
Acid Organocatalysis, HIPOCAT”) is gratefully acknowledged.
We also thank the members of our NMR, MS, and
crystallography departments for their support.
(13) CCDC Deposit Nos. 1029412 and 1029413 for 3e and 3h; see
also SI.
(
14) For examples of the use of interrupted Fischer indole
intermediates in synthesis from Garg group, see (a) Boal, B. W.;
Schammel, A. W.; Garg, N. K. Org. Lett. 2009, 11, 3458. (b) Schammel,
A. W.; Boal, B. W.; Zu, L.; Mesganaw, T.; Garg, N. K. Tetrahedron
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Biomol. Chem. 2011, 9, 5476. (e) Schammel, A. W.; Chiou, G.; Garg,
N. K. J. Org. Chem. 2012, 77, 725. (f) Schammel, A. W.; Chiou, G.;
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