A computational study on a strategy for isolating a stable cyclopentadienyl cation.

A computational study has been carried out to examine the feasibility of generating a simple monocyclic cyclopentadienyl cation that may be sufficiently stable to isolate and handle at ambient temperatures. Using judicious placement of electron-withdrawing groups (CF3) about the ring we have identified a derivative that may approach the stability of isolobal (and isolatable) borole rings, as evaluated by HOMO-LUMO and singlet-triplet gaps. These Cp(+) derivatives may therefore be an attractive target for synthetic isolation.