MASS-SPECTROMETRIC STUDY ON ION-MOLECULE REACTIONS OF CF3-THERMAL ENERGIES( WITH MONOSUBSTITUTED BENZENES CARRYING A HYDROXY OR ALKOXY GROUP AT NEAR)

The gas-phase ion-molecule reactions of CF3+ with monosubstituted benz enes carrying a hydroxy or alkoxy group [PhX: X = OH, CH2OH, CH2CH2OH, CH(OH)CH3: OCH3, and OC2H5] have been studied at near-thermal energie s using an ion-beam apparatus. The major product channels are electrop hilic addition on the O-atom, followed by loss of CF3OH, for ROH (R=Ph , PhCH(2), PhCH(2)CH(2), PhCHCH(3)); while they are electrophilic addi tion to a ring and a substituent, followed by molecular eliminations s uch as HF, C2H4, and PhF, for PhOCH(3) and PhOC(2)H(5). As a minor pro duct channel, charge transfer is found for PhOH, PhOCH(3), and PhOC(2) H(5). The reaction mechanism is discussed based on product ion distrib utions and theoretical calculations of the potential energies of react ion pathways.