New Insight into Chiroptical Properties of 1,2-Diols Cyclic Sulfites.

The present work examines the relationship between the structure and chiroptical properties of cyclic sulfites utilizing the electronic circular dichroism (CD) and time-dependent density functional theory (TD-DFT). For some of the model compounds the study was additionally supported by the X-ray diffraction analysis. A comparison of the experimental and simulated CD spectra gave a reasonable interpretation of the Cotton effects observed in the 200−220 nm spectral range. The study revealed a high sensitivity of the CD spectra with regard to the configuration at the sulfur atom as well as the conformation of the ring bearing the sulfite chromophore. The results demonstrated that such a combined treatment enabled the determination of absolute configuration with a high degree of confidence.