PHOTOOXIDATION OF CINNAMALDEHYDE IN METHANOL - PRODUCT ANALYSIS AND EVOLVING FACTOR-ANALYSIS OF UV SPECTRA

The photooxidation of cinnamaldehyde in methanol was studied by GC/MS, TLC, and UV absorption spectroscopy in the lambda = 200-350 nm region. TLC indicates four components of the reaction mixtures. These components were identified by GC/MS as trans- and cis-cinnamaldehyde and trans- and cis-dimethyl acetal of cinnamaldehyde. Set of the UV absorption spectra of the photooxidation reaction mixtures was analyzed by the Evolving Factor Analysis. Three spectra of components were isolated and the compositions of the reaction mixtures were determined. The isolated spectra correspond to trans- and cis-cinnamaldehyde and dimethyl acetal of cinnamaldehyde. On the basis of the determined compositions of reaction mixtures Principal Components Regression calibration model of the UV spectra set was developed.