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Synlett 2003(11): 1746-1748
DOI: 10.1055/s-2003-41436
LETTER
© Georg Thieme Verlag Stuttgart · New York

Molecular Sieve (MS 4A) Promoted Cyclocondensation of Hindered, Aromatic Nitrile Oxides and Cyclic Diketones under Mild Conditions

Tomoo Matsuura, Jeffrey W. Bode, Yoshifumi Hachisu, Keisuke Suzuki*
Department of Chemistry, Tokyo Institute of Technology and CREST, Japan Science and Technology Corporation, O-okayama, Meguro-ku, Tokyo 152-8551, Japan
Fax: +81(3)57342228; e-Mail: ksuzuki@chem.titech.ac.jp;
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Publication History

Received 6 June 2003
Publication Date:
22 September 2003 (online)

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Abstract

Molecular sieves (MS 4A) serve as efficient promoters for the cyclocondensation of stable, hindered nitrile oxides and a variety of cyclic diketones to afford fused isoxazoles in good yield. The operational simplicity and remarkably mild reaction conditions compliment our amine-promoted cyclocondensation conditions and demonstrate broad substrate scope.

Key words

cycloadditions - ketones - condensation - isoxazoles - molecular sieves

    References

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4

MS 4A have the general formula Na2O·Al2O3·xSiO2·yH2O.