Nuclear magnetic resonance studies of solvent effect on the molecular structure of some aryl and alkyl ethers

Abstract

The nuclear magnetic resonance spectra of several substituted benzyl ethers containing a center of asymmetry reveals that in certain solvents the methylene protons of the ether are magnetically nonequivalent. Further investigation shows that the magnitude of this effect is related to the dielectric constant of the solvent. From this information a structure for the molecule in solution is postulated, and the observed magnetic nonequivalence of the protons is explained on the basis of steric and electronic effects.