GAS-PHASE ORGANOMETALLIC CHEMISTRY - REACTIONS OF AL+ WITH ALKYL-HALIDES

Gas-phase ion-molecule reactions of Al+ with several alkyl halides have been examined using an ion beam appratus. Relative product ion abundances are reported as a function of collision energy over the range 0.5-5 eV. Three types of reactions are observed: (1) halide transfer, (2) dehydrohalogenation, and (3) oxidation. Halide transfer from dichloroalkanes yields chloronium ions, which may eliminate HCl to give allyl cations. Dehydrohalogenation results in elimination of HX with Al+ remaining bound to either HX or the alkene which is concomitantly formed. The relative importance of the halide transfer and dehydrohalogenation products is dependent on the reaction thermodynamics and the collision energy. Reaction of Al+ with CH2ClCH2Cl leads to AlCl2+ and C2H4, a process in which the metal is formally oxidized from the +1 to the +3 state. © 1979.