Aryl rotation PES of tris(pentafluorophenyl)borane

Click on ellipse to view 3D structure in popup window (run JSmol)
image/svg+xml kcal/mol 25 - 20 - 15 - 10 - 5 - 0 - 0.00 kcal M-propeller0.00 kcal 0.00 kcal P-propeller0.00 kcal 6.73 kcal TS26.73 kcal 14.95 kcal TS314.95 kcal 27.49 kcal TS127.49 kcal

Energy (DFT/PBE/L1) without thermochemical, dispersion and solvent corrections.
TS1, TS2 and TS3 are one-, two- and three-ring-flip transition states between M- and P-propellers (Mislow terminology).
TS1 is not quite correct, it has two imaginary frequencies. Zero-ring-flip TS did not work, but, obviously, its energy is much higher.

cf. https://doi.org/10.1002/anie.201704097 (блин, какая халтура в расчетной части! посчитали только TS3, да и то коряво)

Dihedrals 5-2-1-3, 6-3-1-4 and 7-4-1-2 when moving along the IRCs

image/svg+xml -150 -120 -90 -60 -30 0 30 M-propeller P-propeller TS Dihedral one-ring-flip two-ring-flip three-ring-flip

14.01.2020