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Studies in the Helicene Series NMR. Evidence of ‘Helicene-like’ Conformations in the cis 1,2-Diarylethylenes. Part XVII

✍ Scribed by R. H. Martin; Nicole Defay; H. P. Figeys; K. Lê van; J. J. Ruelle; J. J. Schurter

Publisher
John Wiley and Sons
Year
1972
Tongue
German
Weight
242 KB
Volume
55
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

The cis and trans isomers of eight 1,2‐diarylethylenes, precursors of helicenes, have been studied by NMR. spectroscopy. The observed differences in chemical shifts, specific solvent effects and steric effects (bromo derivatives) can be explained by the contribution of ‘helicenelike’ conformers in the cis isomers.

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