Synthesis 2010(23): 4075-4081  
DOI: 10.1055/s-0030-1258289
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of 3-Heteroaryloxindoles through t-BuOCl-Mediated Oxidation of 3-Heteroarylindoles

Marco Baronia, Giordano Lesmab, Letizia Puleioa, Alessandro Sacchettic, Alessandra Silvani*b, Marco Zancheta
a Sanofi-Aventis, Centro Ricerche Sanofi-Midy, Via G. Sbodio 2, 20134 Milano, Italy
b Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, Via G. Venezian 21, 20133 Milano, Italy
Fax: +39(02)50314078; e-Mail: alessandra.silvani@unimi.it;
c Politecnico di Milano, Dipartimento di Chimica, Materiali ed Ingegneria Chimica ‘Giulio Natta’, Via Mancinelli 7, 20131 Milano, Italy
Further Information

Publication History

Received 23 July 2010
Publication Date:
07 October 2010 (online)

Abstract

The oxidation of 3-heteroarylindoles to the corresponding oxindoles with t-butyl hypochlorite has been investigated. Under carefully adjusted conditions, preparative scale of desired products can be achieved. Two competing pathways seem to contribute to the reaction mechanism, affording 3-heteroaryloxindoles bearing hydrogen or chlorine at C3, depending on stereoelectronic factors. The present methodology appears also generally applicable for the preparation of simple 3-aryloxindoles.

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We also included the preparation of compound 3c, which, strictly speaking, is not a heteroaryl derivative, but could serve to test the generality of the proposed methodology.