Nuclear Magnetic Resonance Studies of Sulfur Compounds. II. The Substituent Effect on Geminal Coupling Constants and on Magnetic Nonequivalence of the Methylene Protons of Sulfoxides.

Abstract

Nuclear magnetic resonance spectra were obtained for a number of sulfoxides, whose methylene protons are magnetically nonequivalent. The coupling constants between these protons depend on the electronic properties of the substituent adjacent to the coupling protons. The substituent effect on magnetic nonequivalence was also studied and it is demonstrated that the electronic properties of the substituent constitute an important factor responsible for the magnitude of magnetic nonequivalence.