Premium
Substituent effect on the 1 H NMR Spectra of trans aryl methyl oxiranes and arylpropenes
Author(s) -
Benassi R.,
Lazzeretti P.,
Moretti I.,
Taddei F.,
Torre G.
Publication year - 1973
Publication title -
organic magnetic resonance
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0030-4921
DOI - 10.1002/mrc.1270050809
Subject(s) - substituent , chemistry , aryl , chemical shift , ring (chemistry) , proton , solvent , solvent effects , nmr spectra database , spectral line , proton nmr , medicinal chemistry , stereochemistry , organic chemistry , alkyl , physics , quantum mechanics , astronomy
The 1 H NMR spectra of 1‐aryl‐2‐methyl oxiranes substituted in the phenyl ring and of the corresponding vinyl derivatives have been analysed. The substituent effect on oxiran protons seems mostly polar in character, as shown by correlations with substituent constants, solvent effects and the fact that perturbation decreases with increasing distance from the substituent. The comparison with the corresponding vinyl derivatives, in which conjugation effects are present, confirms this point. The results also seem to exclude the possibility of substituents causing significant changes on the preferred conformation of the phenyl ring. Ring current contributions on oxirane protons, evaluated by SCF procedure, show that their change with substituents is very small and does not represent a significant part of the change of proton chemical shift with substituents.