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Proton-coupled carbon-13 NMR spectra of butadienes

✍ Scribed by Robin K. Harris; Soon Ng; Alan Connelly

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
434 KB
Volume
29
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Proton‐coupled ^13^C NMR spectra were obtained for three methyl‐substituted butadienes, namely 2‐methylbuta‐1,3‐diene, trans‐2‐methylpenta‐1,3‐diene and 2,4‐dimethylpenta‐1,3‐diene. The second‐order spectra were analysed by computer, using some new ^1^H NMR data, and the resulting chemical shifts and coupling constants are reported. The parameters are related to conjugation (and, in turn, to conformation) of the compounds, and to the influence of σ and π pathways for coupling.

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