Chemical modifications of phenoxy resin. Synthesis and1H NMR study of model compounds

The hydroxy group of phenoxy resin has been modified by etherification and esterification. The 1H NMR spectra of these products show large differences in the splitting patterns of the methylene protons according to the chemical nature of the substituent groups. Model compounds for phenoxy resin and derivatives, as well as some other glycerol derivatives, have been synthesized in order to study in more detail the signals of the CH2 group. The 1H NMR spectra of these compounds show two types of splitting. In some cases both protons absorb clearly as a doublet through accidental equivalence, while in other cases they are magnetically non-equivalent. This behaviour can be explained by non uniform conformer populations (JAX ≠ JBX) in some cases, but where JAX ≈ JBX it could not be explained without taking into account the molecular asymmetry.