Organic Letters
Letter
Table 3. Assembly of Isoindolinones, Oxazolidinone, and
Dihydroquinazolinone Catalyzed by Al(OTf)3
AUTHOR INFORMATION
Corresponding Authors
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a
Author Contributions
§These authors contributed equally.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was financially supported by the National Natural
Science Foundation of China (NSFC No. 81102322), PUMC
Youth Fund (No. 3332013072), and the Fundamental Research
Funds for the Central Universities.
REFERENCES
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(1) (a) Brickner, S. J.; Barbachyn, M. R.; Hutchinson, D. K.;
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a
Reaction conditions: All reactions were performed at reflux for 1−4 h
with 1.0 mmol of 1a, 0.5 equiv of Al(OTf)3, and 2.0 equiv of Et3SiH in
5.0 mL of dry acetonitrile. Yield of isolated product.
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Figure 2. X-ray crystal structure of compound 20b.
In conclusion, we have developed an efficient and verstaile
Al(OTf)3-catalyzed cascade cyclization and ionic hydrogenation
method for N-substituted lactams preparation. The reaction is
applicable to a wide range of substrates with various functional
groups to afford the corresponding pyrrolidinones, piperidones,
and structure related heterocycles in moderate to good yields.
The ease of preparation of the nitrogen substituted precursors,
the mild reaction conditions, and the efficiency of this reaction
that enable cyclization and hydrogenation to be attainable in
one step make this protocol an attractive methodology in
organic synthesis.
ASSOCIATED CONTENT
* Supporting Information
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S
Experimental procedures and characterization data for all
compounds and X-ray crystal structure data (CIF) for
compound 20b. This material is available free of charge via
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dx.doi.org/10.1021/ol403173x | Org. Lett. 2014, 16, 190−192