Dehydrogenation of 6-azaquinazoline derivatives. Formation of unexpected quinonediimine intermediates

Imre Huber, F. Fülöp, János Lázár, G. Bernáth, Gábor Tóth

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

2,6-Disubstituted 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one (6-azaquinazoline) derivatives 7a-e were synthesized from N-substituted 3-methoxycarbonyl-4-piperidones 5a, b and amidines 6a-c. Compounds 7a-d and the debenzylated derivatives 8a-c underwent dehydrogenation in xylene or in nitrobenzene in the presence of a palladium-carbon catalyst furnishing products 9a, b and d or 10a-c, respectively. It was found that the formation of the two types of products, 9 or 10, from the same molecules depends on the substituents at positions 2 and 6, and on the inert or oxidative character of the solvent used. The quinonediimine forms 9a, b can be considered to be intermediates of the transformation 7a, b→10a, b.

Original languageEnglish
Pages (from-to)157-162
Number of pages6
JournalJournal of the Chemical Society, Perkin Transactions 1
Issue number1
Publication statusPublished - 1992

Fingerprint

Dehydrogenation
Piperidones
Amidines
Derivatives
Xylenes
Palladium
Carbon
Catalysts
Molecules
nitrobenzene

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Dehydrogenation of 6-azaquinazoline derivatives. Formation of unexpected quinonediimine intermediates. / Huber, Imre; Fülöp, F.; Lázár, János; Bernáth, G.; Tóth, Gábor.

In: Journal of the Chemical Society, Perkin Transactions 1, No. 1, 1992, p. 157-162.

Research output: Contribution to journalArticle

@article{ab00cc7c6bff4a21b51f8fbf4960a4d4,
title = "Dehydrogenation of 6-azaquinazoline derivatives. Formation of unexpected quinonediimine intermediates",
abstract = "2,6-Disubstituted 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one (6-azaquinazoline) derivatives 7a-e were synthesized from N-substituted 3-methoxycarbonyl-4-piperidones 5a, b and amidines 6a-c. Compounds 7a-d and the debenzylated derivatives 8a-c underwent dehydrogenation in xylene or in nitrobenzene in the presence of a palladium-carbon catalyst furnishing products 9a, b and d or 10a-c, respectively. It was found that the formation of the two types of products, 9 or 10, from the same molecules depends on the substituents at positions 2 and 6, and on the inert or oxidative character of the solvent used. The quinonediimine forms 9a, b can be considered to be intermediates of the transformation 7a, b→10a, b.",
author = "Imre Huber and F. F{\"u}l{\"o}p and J{\'a}nos L{\'a}z{\'a}r and G. Bern{\'a}th and G{\'a}bor T{\'o}th",
year = "1992",
language = "English",
pages = "157--162",
journal = "Journal of the Chemical Society, Perkin Transactions 1",
issn = "1472-7781",
publisher = "Chemical Society",
number = "1",

}

TY - JOUR

T1 - Dehydrogenation of 6-azaquinazoline derivatives. Formation of unexpected quinonediimine intermediates

AU - Huber, Imre

AU - Fülöp, F.

AU - Lázár, János

AU - Bernáth, G.

AU - Tóth, Gábor

PY - 1992

Y1 - 1992

N2 - 2,6-Disubstituted 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one (6-azaquinazoline) derivatives 7a-e were synthesized from N-substituted 3-methoxycarbonyl-4-piperidones 5a, b and amidines 6a-c. Compounds 7a-d and the debenzylated derivatives 8a-c underwent dehydrogenation in xylene or in nitrobenzene in the presence of a palladium-carbon catalyst furnishing products 9a, b and d or 10a-c, respectively. It was found that the formation of the two types of products, 9 or 10, from the same molecules depends on the substituents at positions 2 and 6, and on the inert or oxidative character of the solvent used. The quinonediimine forms 9a, b can be considered to be intermediates of the transformation 7a, b→10a, b.

AB - 2,6-Disubstituted 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-4(3H)-one (6-azaquinazoline) derivatives 7a-e were synthesized from N-substituted 3-methoxycarbonyl-4-piperidones 5a, b and amidines 6a-c. Compounds 7a-d and the debenzylated derivatives 8a-c underwent dehydrogenation in xylene or in nitrobenzene in the presence of a palladium-carbon catalyst furnishing products 9a, b and d or 10a-c, respectively. It was found that the formation of the two types of products, 9 or 10, from the same molecules depends on the substituents at positions 2 and 6, and on the inert or oxidative character of the solvent used. The quinonediimine forms 9a, b can be considered to be intermediates of the transformation 7a, b→10a, b.

UR - http://www.scopus.com/inward/record.url?scp=37049067239&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=37049067239&partnerID=8YFLogxK

M3 - Article

SP - 157

EP - 162

JO - Journal of the Chemical Society, Perkin Transactions 1

JF - Journal of the Chemical Society, Perkin Transactions 1

SN - 1472-7781

IS - 1

ER -