Restricted amide rotation with steric hindrance induced multiple conformations

Viswanathan V Krishnan, Salvador Vazquez, Kalyani Maitra, Santanu Maitra

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The C–N bond character is dependent directly upon the resonance-contributor structure population driven by the delocalized nitrogen lone-pair of electrons. In the case of N, N-dibenzyl-ortho-toluamide (o-DBET), the molecule adopts subpopulations of conformers with distinct NMR spectral features, particularly at low temperatures. This conformational adaptation is unique to o-DBET, while the corresponding meta- and para- forms do not show such behavior. Variable-temperature (VT) NMR, two-dimensional exchange spectroscopy (EXSY), and qualitative molecular modeling studies are used to demonstrate how multiple competing interactions such as restricted amide rotation and steric hindrance effects can lead to versatile molecular adaptations in the solution state.

Original languageEnglish (US)
Pages (from-to)148-151
Number of pages4
JournalChemical Physics Letters
Volume689
DOIs
StatePublished - Dec 1 2017

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Amides
amides
Conformations
Nuclear magnetic resonance
nuclear magnetic resonance
Molecular modeling
Nitrogen
Spectroscopy
nitrogen
Temperature
Molecules
Electrons
spectroscopy
molecules
electrons
interactions
temperature

Keywords

  • Chemical exchange
  • Dynamic NMR
  • Restricted amide rotation
  • Steric hindrance

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this

Restricted amide rotation with steric hindrance induced multiple conformations. / Krishnan, Viswanathan V; Vazquez, Salvador; Maitra, Kalyani; Maitra, Santanu.

In: Chemical Physics Letters, Vol. 689, 01.12.2017, p. 148-151.

Research output: Contribution to journalArticle

Krishnan, Viswanathan V ; Vazquez, Salvador ; Maitra, Kalyani ; Maitra, Santanu. / Restricted amide rotation with steric hindrance induced multiple conformations. In: Chemical Physics Letters. 2017 ; Vol. 689. pp. 148-151.
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