Mechanistic and kinetic study on the ozonolysis of 2,4-hexadienedial

Abstract

The formation and unimolecular reactions of primary ozonides and carbonyl oxides arising from the O3-initiated reactions of 2,4-hexadienedial (HDE) have been investigated using the density functional theory and ab initio method. The activation energies of O3 cycloaddition to the >C=C C=O bonds of HDE for the formation primary ozonides (POZ1 and POZ2) are 4.79 and 21.37 kcal mol−1, respectively, implying that the initial O3 to the >C=C C=C C=O bonds of HDE more difficult than to >C=C C=O bond of formaldehyde. The largest rate constants of OH formation and dioxirane formation in the unimolecular reactions of carbonyl oxides are 6.13 × 10−4 and 7.93 × 10−1 s−1 at 300 K, respectively. The dioxirane is main product in the unimolecular reaction of the carbonyl oxides arising from the O3-initiated reaction of HDE.