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Synlett 2004(10): 1832-1834  
DOI: 10.1055/s-2004-829555
LETTER
© Georg Thieme Verlag Stuttgart · New York

Ytterbium Triflate Promoted Synthesis of Benzimidazole Derivatives

Massimo Curini*, Francesco Epifano, Francesca Montanari, Ornelio Rosati, Sara Taccone
Dipartimento di Chimica e Tecnologia del Farmaco - Sezione di Chimica Organica, Università di Perugia, Via del Liceo, 06123 Perugia, Italy
Fax: +39(075)5855116; e-Mail: curmax@unipg.it;
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Publikationsverlauf

Received 24 March 2004
Publikationsdatum:
15. Juli 2004 (online)

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Abstract

Differently substituted benzimidazoles have been synthesised in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of Yb(OTf)3 as catalyst. The method is applicable to aromatic, unsaturated and ­aliphatic aldehydes and to substituted o-phenylenediamines without significant differences.

Key words

aldehydes - benzimidazoles - catalysis - lanthanides

    References

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14

The reaction to yield compound 1 has been repeated three times, through the catalyst washed with CH2Cl2 and dried for 2 h at 70 °C with the following yields: 94%, 91%, and 91%.