Organic Letters
Letter
Notes
nitrile products, the tetrahydro-β-carboline 3r-B was smoothly
obtained by applying the reduction of 3r and the Pictet−
Spengler cyclization sequence. Furthermore, the δ-disubstituted
ε-caprolactam 3w-B can be efficiently synthesized via selective
hydrogenation of 3w and an intramolecular condensation
reaction procedure (Scheme 3b).
When measuring the selectivity outcome of the reaction, we
were surprised to observe that our transformation features an
enantioselective potential (eq 1). For example, when analyzing
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was financially supported by the Recruitment
Program of Global Experts and the startup funding from
Shanghai Jiao Tong University. We thank Dr. Bastien Cacherat
(SIOC, Shanghai) for critical proofreading of this manuscript.
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ASSOCIATED CONTENT
* Supporting Information
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The Supporting Information is available free of charge at
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AUTHOR INFORMATION
Corresponding Author
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Xianjie Fang − Shanghai Jiao Tong University, Shanghai,
(9) Yanagisawa, A.; Nezu, T.; Mohri, S.-i. Org. Lett. 2009, 11, 5286−
5289.
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Organic Synthesis: Building Blocks and Fine Chemicals; Beller, M., Bolm,
C., Eds.; Wiley-VCH: Weinheim, Germany, 2008; Chapter 2.5.
Other Authors
Yidan Xing − Shanghai Jiao Tong University, Shanghai,
People’s Republic of China
Rongrong Yu − Shanghai Jiao Tong University, Shanghai,
People’s Republic of China
(b) Bini, L.; Mu
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