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Synlett 2018; 29(14): 1892-1896
DOI: 10.1055/s-0037-1610502
letter
© Georg Thieme Verlag Stuttgart · New York

Efficient Synthesis of Indole Derivatives Containing the Tetrazole Moeity Utilizing an Ugi-Azide Post-Transformation Strategy

Ali Nikbakht
a   Peptide Chemistry Research Center, K. N. Toosi University of Technology, P. O. Box 15875-4416, Tehran, Iran   Email: balalaie@kntu.ac.ir
,
Saeed Balalaie  *
a   Peptide Chemistry Research Center, K. N. Toosi University of Technology, P. O. Box 15875-4416, Tehran, Iran   Email: balalaie@kntu.ac.ir
b   Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
,
Fatemeh Baghestani
a   Peptide Chemistry Research Center, K. N. Toosi University of Technology, P. O. Box 15875-4416, Tehran, Iran   Email: balalaie@kntu.ac.ir
,
Frank Rominger
c   Organisch-Chemisches Institut der Universitaet Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
› Author AffiliationsWe thank the National Institute for Medical Research Development (NIMAD, Project No. 963388) for financial support.
Further Information

Publication History

Received: 04 April 2018

Accepted after revision: 29 June 2018

Publication Date:
26 July 2018 (online)

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Dedicated to Prof. Bernhard Breit on the occasion of his birthday

Abstract

An efficient strategy has been developed for the synthesis of indole derivatives containing the tetrazole moiety using a AuCl3-catalyzed cyclization reaction. The precursors of the cycloadduct were easily prepared by an Ugi-azide 4-CR in methanol at room temperature. The merit of this protocol lies in its operational simplicity, readily available starting materials, high yields of product, and good functional group tolerance.

Key words

Ugi-azide post-transformation strategy - metal catalyzed alkyne cyclization - heterocyclization - indole - tetrazole

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1610502.
  • Supporting Information
 

  • References and Notes

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