Conformational complexity in seven-membered cyclic triazepinone/open hydrazones. 1. 1D and 2D variable temperature NMR study

Kalevi Pihlaja, Mario F. Simeonov, F. Fülöp

Research output: Contribution to journalArticle

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Abstract

The stereochemistry and conformational behavior of a series of 22 2- methyl-2-alkyl(phenyl, aryl)-4-N-methyl-1,2,3,4-tetrahydro-5H-1,3,4- benzotriazepin-5-ones and their open-chain hydrazone tautomers in various solvents were studied by 1D and 2D NMR techniques in the temperature range from 193 K to 410 K. Molecular rearrangements involving interconversions of the ring and open-chain forms (the latter via amide bond and Z/E C=N double bond isomerization), pseudorotation of the ring forms, and N-inversion processes with different rates on the NMR time scale took place, leading to the observation of average and deceptively simple 1H and 13C NMR spectra for most of them at room temperature.

Original languageEnglish
Pages (from-to)5080-5088
Number of pages9
JournalJournal of Organic Chemistry
Volume62
Issue number15
DOIs
Publication statusPublished - Jul 25 1997

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Hydrazones
Nuclear magnetic resonance
Stereochemistry
Isomerization
Amides
Temperature
triazepinone

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Conformational complexity in seven-membered cyclic triazepinone/open hydrazones. 1. 1D and 2D variable temperature NMR study. / Pihlaja, Kalevi; Simeonov, Mario F.; Fülöp, F.

In: Journal of Organic Chemistry, Vol. 62, No. 15, 25.07.1997, p. 5080-5088.

Research output: Contribution to journalArticle

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