Mass-Spectrometric Study on Ion-Molecule Reactions of CF3+ with PhX at Near-Thermal Energy

Article abstract of DOI:10.1246/bcsj.68.3497

The gas-phase ion-molecule reactions of CF3⁺ with benzene, toluene, ethylbenzene, styrene, and ethynylbenzene have been studied at near-thermal energy using an ion-beam apparatus.The major product channels are electrophilic addition followed by HF elimination for benzene (93.4+/-2.2percent), toluene (84.3+/-2.4percent) and ethynylbenzene (76.9+/-0.9percent).The dominant product channels for ethylbenzene are electrophilic addition followed by C2H4 and C2H4+HF eliminations (78.9+/-4.7percent), while those for styrene are electrophilic addition followed by one or two HF eliminations and C2H2F2 elimination (91.7+/-0.4percent).Only ethynylbenzene gives an initial adduct ion with a small branching ratio of 6.2+/-0.4percent.As minor product channels, hydride transfer occurs for benzene (6.6+/-2.2percent) and toluene (7.8+/-1.5percent), and charge transfer takes place for toluene (7.9+/-2.0percent), styrene (8.3+/-1.4percent), and ethynylbenzene (6.2+/-0.4percent).The reaction mechanisms are discussed on the basis of product ion distributions and semi-empirical calculations of potential energies of reaction pathways.