Alfa-Pyridoin Tautomerism - Reducing Difference Infrared Spectral Analysis

The existence of diol and oxidized diketoforms in chloroform of -pyridoin was established using reducing-difference IR-spectral analysis for non-polarized spectra interpretation. The linear-dichroic IR-spectral analysis of the compound, studied in nematic liquid crystal solution, showed stabilization of the diolic tautomer. Detailed vibrational assignment of the corresponding modes was carried out using reduced-difference procedure for polarized spectra interpretation. The experimental results were completed and enlarged with theoretical ab initio calculations.