An exploratory study on the oxo-enol tautomerization of selected dioxopiperazines and their sulphur-containing analogues

O. Farkas, A. Perczel, Gyula Szókàn, M. Hollósi, Márton Kajtár

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The ring structures of selected dioxopiperazines and their sulphur-containing analogues undergo remarkable geometry changes during enolization as established by semiempirical (AM1) and non-empirical (HF/3-21G) MO computations. The dienols attempt to lose their "pseudo-anti-aromatic" or "anti-aromatoid" character by three plausible mechanisms: (i) changing the CX bond length; (ii) changing the NH out-of-plane angle; (iii) changing the planarity/non-planarity of the six-membered ring. The effectiveness of these three mechanisms is discussed for cyclo(Gly-Gly), cyclo(Ala-Ala), cyclo(Pro-Pro) and their dithio derivatives cyclo(Glyt-Glyt, cyclo(Alat-Alat), cyclo(Prot-Prot).

Original languageEnglish
Pages (from-to)131-148
Number of pages18
JournalJournal of Molecular Structure: THEOCHEM
Volume286
Issue numberC
DOIs
Publication statusPublished - Oct 29 1993

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Bond length
Sulfur
sulfur
analogs
Derivatives
Geometry
ring structures
rings
geometry
2,5-dioxopiperazine
cyclo(prolylprolyl)
cyclo(alanylalanyl)

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Computational Theory and Mathematics
  • Atomic and Molecular Physics, and Optics

Cite this

An exploratory study on the oxo-enol tautomerization of selected dioxopiperazines and their sulphur-containing analogues. / Farkas, O.; Perczel, A.; Szókàn, Gyula; Hollósi, M.; Kajtár, Márton.

In: Journal of Molecular Structure: THEOCHEM, Vol. 286, No. C, 29.10.1993, p. 131-148.

Research output: Contribution to journalArticle

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