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Synthesis 2003(11): 1671-1678
DOI: 10.1055/s-2003-40884
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of 2-Aryl-1-hydroxyazaindoles and 2-Arylazaindoles via Oxidation of o-Hydroxyaminostyrylpyridines

Daniel Kuzmich*, Carol Mulrooney
Boehringer-Ingelheim Pharmaceuticals, Inc., Department of Medicinal Chemistry, Ridgefield, Connecticut 06877-0368, USA
Fax: +1(203)7916072; e-Mail: dkuzmich@rdg.boehringer-ingelheim.com;
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Publication History

Received 22 May 2003
Publication Date:
25 July 2003 (online)

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Abstract

2-Aryl-1-hydroxyazaindoles (pyrrolopyridin-1-ols) are prepared via an oxidation/cyclization of o-hydroxyaminostyrylpyridines with DDQ. Reduction of the N-OH bond affords the corresponding 2-arylazaindoles (1H-pyrrolopyridines). The scope of the cyclization is explored via (i) the condensation of 4-methyl-3-nitropyridine with various aryl aldehydes to afford 2-aryl substituted 6-azaindoles and, (ii) the synthesis of 2-phenyl-4-, 5- and 7-azaindoles.

Key words

azaindoles - 1N-hydroxy azaindoles - cyclization - oxidation - 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) - pyrrolopyridines

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