Ir and pmr spectra of 2-aryl-4-thiazolidinones. III. Stereochemical analysis of 2-aryl-3-(2-pyridyl)-4-thiazolidinones

The long-range coupling through the sulphur atom observed in a number of 2-aryl-3-(2-pyridyl)-4-thiazolidinones suggests that the C₂ proton and one of methylene protons are in a cis 1,3 diequatorial relationship. Some additional information concerning the preferred orientations of the substituents in this system are given from Eu(fod)₃, [tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dionato)]europium, induced shift data.