The photochemical reactions of two isotopically labeled vinyl acetates (vinyl carbon-13 and deuterated) in inert gas matrices were investigated using FTIR analysis. The infrared spectrum of each monomer at various concentrations was studied in the following inert gas solids: argon, nitrogen, and krypton. The vinyl acetate-inert gas combinations were then exposed to UV radiation in order to promote photolysis. Each IR spectrum was analyzed for pre- and post-photolysis absorbances and the assignment of peaks was compared to theoretical assigning proposed structures. The purpose of these experiments was to determine the conformation of vinyl acetate in the gas phase and to identify its photoproducts using the isotopically labeled compounds. The cis-trans conformer was determined to be prevalent by comparing the frequencies and intensities of the experimental vinyl acetate to the theoretical calculated structure. Analysis of the spectra indicated the formation of water, carbon monoxide, ketene, carbon dioxide, methane, acetaldehyde, methyl, and nitrous oxide (only in the nitrogen matrix) as photoproducts of both vinyl 13C2 acetate and vinyl acetate-d6. The most predominant peaks found in all gas matrices were those from carbon monoxide, carbon dioxide, ketene, and acetaldehyde. Vinyl acetate appeared to break down to acetyl and vinoxy with hydrogen abstraction from the vinoxy to form acetaldehyde and ketene. The nitrous oxide was formed by the donation of an oxygen atom from the vinoxy radical to the nitrogen molecule.
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