Reactivity and regioselectivity of hydroxyl radical addition to halogenated ethenes

A detailed study was conducted to investigate the reaction mechanisms and regioselectivity of ethene, fluoroethene and chloroethene reactions with hydroxyl (OH) radicals. Four stationary points were found along the MEP and geometries were optimized while vibrational frequencies were calculated at the UMP2/6-311+G(2d.p) level of theory. Structures of pre-reaction complexes determined at the reactant side of the MEP are characterized by the weak interaction between the hydrogen atom the OH radical and the pi electron density.