Organic Letters
Letter
Lewis base catalysis for direct Mannich reactions. Chem. Commun.
2011, 47, 2360−2362. (f) Boess, E.; Sureshkumar, D.; Sud, A.; Wirtz,
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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S
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C.; Fares, C.; Klussmann, M. Mechanistic Studies on a Cu-Catalyzed
Aerobic Oxidative Coupling Reaction with N-Phenyl Tetrahydroiso-
quinoline: Structure of Intermediates and the Role of Methanol As a
Solvent. J. Am. Chem. Soc. 2011, 133, 8106−8109. (g) Boess, E.;
Schmitz, C.; Klussmann, M. A Comparative Mechanistic Study of Cu-
Catalyzed Oxidative Coupling Reactions with N-Phenyltetrahydroi-
soquinoline. J. Am. Chem. Soc. 2012, 134, 5317−5325. (h) Ratnikov,
M. O.; Doyle, M. P. Mechanistic Investigation of Oxidative Mannich
Reaction with tert-Butyl Hydroperoxide. The Role of Transition Metal
Salt. J. Am. Chem. Soc. 2013, 135, 1549−1557.
(3) For reviews of amine functionalization by catalytic oxidation of
α-amino C−H bonds, see: (a) Murahashi, S.; Zhang, D. Ruthenium
catalyzed biomimetic oxidation in organic synthesis inspired by
cytochrome P-450. Chem. Soc. Rev. 2008, 37, 1490−1501. (b) Li, C.-J.
Cross-Dehydrogenative Coupling (CDC): Exploring C−C Bond
Formations beyond Functional Group Transformations. Acc. Chem.
Res. 2009, 42, 335−344. (c) Girard, S. A.; Knauber, T.; Li, C.-J. The
Cross-Dehydrogenative Coupling of Csp3−H Bonds: A Versatile
Strategy for C−C Bond Formations. Angew. Chem., Int. Ed. 2014, 53,
74−100.
Experimental procedures and spectral data for all new
AUTHOR INFORMATION
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Corresponding Author
ORCID
Author Contributions
†These authors contributed equally.
Notes
The authors declare no competing financial interest.
(4) For recent advances of oxidant-free Mannich-type reactions
through α-amino C−H functionalization, see: (a) Chen, W.; Seidel,
D. The Redox-Mannich Reaction. Org. Lett. 2014, 16, 3158−3161.
(b) Ma, L.; Seidel, D. Intramolecular Redox-Mannich Reactions:
Facile Access to the Tetrahydroprotoberberine Core. Chem. - Eur. J.
2015, 21, 12908−12913. (c) Chen, W.; Seidel, D. Redox-Annulation
of Cyclic Amines and β-Ketoaldehydes. Org. Lett. 2016, 18, 1024−
1027.
ACKNOWLEDGMENTS
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We are grateful for financial support from the National
Institutes of Health (No. GM-128695) and Boston College.
We are thankful to Professor Amir H. Hoveyda (Boston
College), Ms. Diana C. Fager (Boston College), and Mr.
Richard Y. Liu (MIT) for helpful discussions.
(5) (a) Chan, J. Z.; Yao, W.; Hastings, B. T.; Lok, C. K.; Wasa, M.
Direct Mannich-Type Reactions Promoted by Frustrated Lewis Acid/
Bronsted Base Catalysts. Angew. Chem., Int. Ed. 2016, 55, 13877−
13881. (b) Shang, M.; Cao, M.; Wang, Q.; Wasa, M. Enantioselective
Direct Mannich-Type Reaction Catalyzed by Frustrated Lewis Acid/
Brønsted Base Complexes. Angew. Chem., Int. Ed. 2017, 56, 13338−
13341.
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