| Abstract: | The appearance potentials for [C11H9]+ from 1, e.g. 2-(chloromethyl)-naphthaline and 1-chloro-phenyl-(5)-penten-(2)-yne-(4), and for [C9H7]+ from indene, phenyl-propyne and phenyl-(5) penten-(2)-yne-(4)-ol-(1), have been correlated with thermochemical data to obtain the enthalpy of formation of the fragment-ions. A comparison between these enthalpies of formation and the values of enthalpy of hypothetical model structures shows that the [C11H9]+ ion is probably best represented as a benztropylium-ion and the [C9H7]+ ion as an ethynyl-tropylium-ion or as a phenylcyclopropenyl-cation. Open chain structures can be eliminated in all cases investigated. |
