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Organic & Biomolecular Chemistry
Page 4 of 5
DOI: 10.1039/C8OB01321G
ARTICLE
Journal Name
In conclusion, we have demonstrated a new method for the
synthesis of quinolines from easily available enones and 2-
aminobenzyl alcohols by utilizing a commercially available
catalyst system. The mechanism investigation indicates it
undergoes a hydrogen-transfer coupling strategy that enables
the synthetic protocol in an atom- and step-economic fashion
together with the merits of broad substrate scope, mild
conditions, operational simplicity, no need for external
reducing reagents and water as the only by-product, which
offers a practical alternative to access quinoline derivatives.
Conflicts of interest
There are no conflicts to declare.
Scheme 6 Control experiments.
Acknowledgements
Based on metal-catalyzed TH mechanism reported in the
literatures16 and the above control experiments, a plausible
reaction pathway is proposed in Scheme 7. First, IrCp*Cl2 and
t-BuOK proceed a ligand exchange process to generate
We gratefully acknowledge the financial support by Nantong
University, the Natural Science Foundation of China (Grant
Nos. 81302628), the Project of “Jiangsu Six Peaks of Talent”
(2014-SWYY-044 and 2016-SWYY-CXTD-008), the Project of
“Jiangsu 333 high-level talents”, and also thank the testing
service provided by Analysis and Testing Center in Nantong
University.
complex
to give alkoxide
aminobenzaldehyde 1’ and metal hydride
undergoes coordination with and then experience
hydrometallation to afford intermediate . Subsequently, with
the alcoholysis of by alcohol , transfer hydrogenation
product ketone 2’ is produced, and alkoxide is regenerated
A
which upon reaction with 2-aminobenzyl alcohol
which followed by β-H elimination to form 2-
. Next, enone
1
B
C
2
C
E
E
1
Notes and references
B
to accomplish the catalytic cycle. Finally, the formed 2-
aminobenzaldehyde 1’ and ketone 2’ undergoes the classic
Friedländer annulation with the assist of t-BuOK to provide the
1
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3
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Conclusions
4 | J. Name., 2012, 00, 1-3
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