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Unusual deuterium isotope effects in 13C NMR spectra of trans-stilbene

✍ Scribed by Ziatko Meić; Dražen Vikić-topić; Hans Güsten

Publisher
John Wiley and Sons
Year
1984
Tongue
English
Weight
823 KB
Volume
22
Category
Article
ISSN
0749-1581

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✦ Synopsis

A detailed analysis of the -C NMR spectra of trans-stilbene and ten deuteriated trans-stilbenes has been undertaken. Some unusual deuterium isotope effects on carbon-hydrogen spin-spin coupling constants could not be explained by the ordinary primary and secondary isotope effects. The positive and negative changes of "J(CH) were interpreted in terms of a steric effect, the vibrational influence of the C-D bond and the para-effect induced by deuterium. In this respect, deuterium behaves as a real substituent with electronic properties different from those of hydrogen. The deuterium isotope effects on -C NMR chemical shifts and carbon-deuterium coupling constants have also been determined.

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