Use to effect regiospecific control

The use of fluorine atom for achieving regiospecific control over the ring closures of tertiary bicyclic cations is demonstrated. The rearrangement of fluorine-synthesized cyclopentenols are studied to establish the stereochemistry of their tetrasubstituted fluoro alkene bonds. Results show that the fluorine atom is capable of controlling the regiochemistry to produce a stable product with a 6-membered ring.