Premium
NMR studies on bridged polycyclic compounds: Spin system transitions due to induced solvent shifts
Author(s) -
Ramey Kermit C.,
Moriarty Robert M.,
Gopal Harsh,
Adams Timothy
Publication year - 1969
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.1270010203
Subject(s) - chemistry , bicyclic molecule , heptane , solvent , methylene , octane , chemical shift , decane , resonance (particle physics) , lactone , solvent effects , stereochemistry , computational chemistry , medicinal chemistry , organic chemistry , physics , particle physics
An NMR study of some bridged bicyclo and tricyclo compounds yielded unusual spectra with respect to solvent effects and virtual coupling. As is the general case for most large polycyclic systems a complete analysis of the spectrum is not possible and the structural details derived from NMR are based on a partial analysis of the spectrum. If the accessible resonances correspond to protons adjacent to methylene groups, the resonance patterns and the chemical shifts may be strongly dependent upon solvent. For 6‐ endo ‐hydroxy, bicyclo[2.2.1]heptane‐2, endo ‐carboxylic acid lactone (1), 6‐ endo ‐hydroxy, 2‐ exo ‐methyl‐bicyclo[2.2.2]octane‐2‐ endo ‐carboxylic acid lactone (2), and exo ‐3,4, exo ‐8,9‐diepoxy, endo ‐tricyclo[5,2,1,0 2,6 ]decane (3), resonances for each fall in this class and the change induced by solvent are attributed to virtual coupling as well as a change in the overall splitting pattern.