Nitrogen bridgehead compounds. Part 76 Synthesis and stereochemistry of ethyl 9‐benzylidene‐6,7,8,9‐tetrahydro‐2‐oxo‐2H‐ and 4‐oxo‐4H‐pyrido[1,2‐a]pyrimidine‐3‐carboxylates and their homologues

Judit Sipos, Benjamin Podányi, I. Hermecz, Levente Pusztay, Gábor Tóth, László Szilágyi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Ethyl 4‐oxo‐6,7,8,9‐tetrahydro‐4H‐pyrido[1,2‐a]pyrimidine‐3‐carboxylates 1–4, their piperidine ring homologues 5–6 and their 2‐oxo isomers 7–9 were reacted with benzaldehyde. At low temperature, kinetically stable addition products were formed. Thermodynamically stable condensation products were obtained at higher temperature, which were also formed when the addition products were refluxed in benzene. The 9‐benzyl derivatives were prepared by the hydrogenation of the condensation products over Pd/C. The stereochemical features of the new compounds were determined via 1H and 13C nmr chemical shift and coupling constant analysis and NOE measurements.

Original languageEnglish
Pages (from-to)1061-1068
Number of pages8
JournalJournal of Heterocyclic Chemistry
Volume26
Issue number4
DOIs
Publication statusPublished - 1989

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Nitrogen Compounds
Stereochemistry
Condensation
Chemical shift
Benzene
Isomers
Hydrogenation
Derivatives
Temperature
benzaldehyde
piperidine

ASJC Scopus subject areas

  • Organic Chemistry

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Nitrogen bridgehead compounds. Part 76 Synthesis and stereochemistry of ethyl 9‐benzylidene‐6,7,8,9‐tetrahydro‐2‐oxo‐2H‐ and 4‐oxo‐4H‐pyrido[1,2‐a]pyrimidine‐3‐carboxylates and their homologues. / Sipos, Judit; Podányi, Benjamin; Hermecz, I.; Pusztay, Levente; Tóth, Gábor; Szilágyi, László.

In: Journal of Heterocyclic Chemistry, Vol. 26, No. 4, 1989, p. 1061-1068.

Research output: Contribution to journalArticle

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