Computational NMR as Useful Tool for Predicting Structure and Stereochemistry of Four-Membered Sulfur Heterocycles

We report a computational NMR study of stereochemically challenging thietane 1-oxides. Comparison of calculated and experimental data allows to assign structure and stereochemistry to the examined molecules. Computations included full conformational analysis of each thietane, DFT geometry optimizations and GIAO NMR calculations. Among the possible stereoisomers, only the computed structures with the correct stereochemistry were found to fit experimental NMR spectroscopic data. Computational analysis provide useful information on the conformational ring preference not easy to disclose by conventional structural analysis.