A reexamination of the molecular mechanism of the Diels–Alder reaction between tetrafluoroethene and cyclopentadiene

DFT calculation results shed a new light on the mechanism of cycloaddition reaction between tetrafluoroethene and cyclopentadiene. The unique influence of fluorine atoms on the ethylene derivative molecule causes the [2 + 2] cycloaddition process to take place according to a stepwise, biradical mechanism. At the same time, the competitive and independent path leads to a one-step (and not a two-step, as was once thought) cycloaddition reaction leading to a [2 + 4] cycloadduct.