2,2,3,3-Tetrafluoronickelacyclopentanes Generated via the Oxidative Cyclization of Tetrafluoroethylene and Simple Alkenes: A Key Intermediate in Nickel-Catalyzed C–C Bond-Forming Reactions

Oxidative cyclization of tetrafluoroethylene
(TFE) and ethylene
with Ni(0) resulted in the formation of a five-membered nickelacycle.
In the presence of PPh3 as an auxiliary ligand, the partially
fluorinated five-membered nickelacycle was isolated and the structure
was determined by X-ray analysis. This nickelacycle was found not
only to react stoichiometrically with enones to give a cross-trimerization
product but also to be a key reaction intermediate in the Ni(0)-catalyzed
cotrimerization of TFE and ethylene, leading to 5,5,6,6-tetrafluoro-1-hexene.