Selected ion flow tube studies of the reactions of H_3O~+, NO~+ and O_2~+ with some chloroalkanes and chloroalkenes

摘要

We describe the results of a selected ion flow tube study of the reactions of H_3O~+, NO~+ and O_2~+ with the chloromethanes CH_3Cl, CH_2Cl_2, CHCl_3, and CCl_4, the chloroethanes CH_2ClCH_2Cl, CH_3CHCl_2, CH_3CCl_3, and CHCl_2CHCl_2, and the chloroethylenes CHClCCl_2 and C_2Cl_4. The H_3O~+ reactions with these molecules, M, are mostly rapid but unusually varied, the most evident processes being direct proton transfer producing MH~+ ions, ion/molecule association producing H_3O~+.M ions, HCl elimination from the protonated molecule producing (M-Cl)~+ ions, and even incorporation of H_2O into the ion with the elimination of one or two HCl molecules. The NO~+ reactions are generally slow and proceed largely via ion/molecule association producing NO~+.M ions. Only one of the reactions, that of CH_3CCl_3, is fast and proceeds via Cl~- transfer producing CH_3CCl_2~+ and an NOCl molecule. The O_2~+ reactions are apparently all fast and proceed via charge transfer producing the parent cations M~+ and via dissociative charge transfer with the elimination of Cl atoms and HCl molecules. In only one of these O_2~+ reactions (that with CHCl_2CHCl_2) is the carbon-carbon bond broken.