Atmospheric photooxidation of diterbutil malonate

WALTER PELÁEZ; FABIO E. MALANCA; DIANA P. HENAO A.

Santiago

Congreso; 25th InterAmerican Photochemical Society Meeting (25th IAPS Meeting); 2016

IAPS (InterAmerican Photochemical Society)

Malonic acid diesters are widely used in the chemical industry as intermediates for the synthesis of a variety of organic chemicals and as the building blocks of different processes in which malonates are used as intermediates, such as pharmaceuticals, agrochemicals, vitamins, fragrances, and dyes. To improve our knowledge of the atmospheric chemistry of malonic acid diesters, we report here the kinetic results of the chlorine-atom-initiated oxidation of di-tert-butyl malonate (DTBM), which allow as determine their photooxidation mechanism.The rate constant of the reaction between DTBM and chlorine atoms was measured relative to cyclohexane and pentane. Photolysis were performed in a photo-reactor using black lamps. Control experiments were performed in the dark for different periods of time in order to discount the among of DTBM that will disappeared by dark reactions. The identification and quantification of reactants and products were performed by infrared spectroscopy. All the experiments were carried out in gas phase. Theoretical calculations were carried out using Gaussian 09 to corroborate the main path of the mechanism reactions.The identification of products and the kinetics analysis lead to the conclusion that chlorine atoms attack the DTBM mainly in the methyl group.The theoretical calculations explain the formation of the products of fotooxidation and agree with the experimental quantification of the main path of the mechanism reactions.