Concerted [4 + 2] and Stepwise (2 + 2) Cycloadditions of Tetrafluoroethylene with Butadiene: DFT and DLPNO-UCCSD(T) Explorations
Dennis Svatunek, Ryan P. Pemberton, Joel L. Mackey, Peng Liu, K. N. Houk
Abstract
groups in the 4 + 2 transition state. We have explored the full potential energy surface for the concerted and stepwise reactions of tetrafluoroethylene and butadiene with density functional theory, DFT (B3LYP and M06-2X), DLPNO-UCCSD(T), and CASSCF-NEVPT2 methods and with the distortion/interaction-activation strain model to explain the energetics of different pathways. The 2 + 2 cycloadduct is formed by an anti-transition state followed by two rotations and a final bond formation transition state. Energetics are compared to the reaction of maleic anhydride and ethylene.
Topics & Concepts
TetrafluoroethyleneChemistryCycloadditionTransition stateKinetic controlMaleic anhydrideComputational chemistryDensity functional theoryIsomerizationPotential energy surfaceKinetic energyPhotochemistryPhysical chemistryOrganic chemistryMoleculeCatalysisPhysicsQuantum mechanicsCopolymerPolymerOrganic Chemistry Cycloaddition ReactionsAdvanced Chemical Physics StudiesCatalysis and Oxidation Reactions