1.
Org Biomol Chem
; 13(45): 11026-38, 2015 Dec 07.
Article
in English
| MEDLINE
| ID: mdl-26393412
ABSTRACT
A systematic investigation of the influence of substitution at positions C-2 and C-3 on the azulenone skeleton, based on NMR characterisation, is discussed with particular focus on the impact of the steric and electronic characteristics of substituents on the position of the norcaradiene-cycloheptatriene (NCD-CHT) equilibrium. Variable temperature (VT) NMR studies, undertaken to enable the resolution of signals for the equilibrating valence tautomers revealed, in addition, interesting shifts in the equilibrium.