Ion-molecule reactions of substituted cyclopropanes by ion cyclotron resonance spectroscopy

Abstract

The gas phase ion chemistry of cyclopropane and a variety of its monosubstituted derivatives (c-C/sub 3/H/sub 5/X, with X = H, Cl, NH/sub 2/, CN, OH, and COCH/sub 3/) has been investigated utilizing ion cyclotron resonance techniques. Reactions of ions with cyclopropane involve most prominently formation of a reaction intermediate from which loss of ethylene and to a lesser extent loss of methyl or ethyl radical occurs. The ion chemistry of substituted cyclopropanes is dominated entirely by the substituent and is markedly different from cyclopropane. In addition to the increased prominence of the protonated parent ion and its corresponding association products, loss of neutrals HX (e.g., HCl) from reaction intermediates becomes significant. Ion-molecule reaction rate constants are extracted and compared for the important reaction pathways of each of the cyclopropanes examined. 26 references, 6 figures, 3 tables.