GAS-PHASE GENERATION OF TRIFLUOROMETHYL CYCLOPENTADIENIDES

Tetramethyltrifluoromethylcyclopentadienide 1a is unstable in solution but it can be readily generated in the gas phase. The proton affiniti es and fluoride binding energies of la and several other trifluorometh yl substituted cyclopentadienides are measured. The data is found to f it an additivity scheme, which suggests that pentakis(trifluoromethyl) cyclopentadiene is an exceptionally strong gas-phase acid, and indicat es that substituted trifluoromethylcyclopentadienides may be accessibl e in solution under the appropriate reaction conditions.