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Molecular structure and the indirect spin–spin coupling constants in azulene—a proton NMR study in the nematic phase

✍ Scribed by S. Arumugam; A. C. Kunwar; C. L. Khetrapal

Publisher
John Wiley and Sons
Year
1981
Tongue
English
Weight
216 KB
Volume
17
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The proton NMR spectrum of azulene has been investigated in the nematic phase of a liquid crystal. Spectral analysis provided the direct dipole‐dipole coupling constants which were used to derive the structural information. It was found that the relative proton‐proton distances in the 7‐ and 5‐membered rings deviate significantly from those for regular heptagons and pentagons. Indirect spin‐spin couplings were also obtained. Many of the inter‐ring and long‐range couplings have magnitudes between 0.2–0.8 Hz.

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