Geometry optimizations and electronic energy calculations used the M06-2X density functional, in conjunction with the TZVP basis set or using the MN15 density functional in combination with the def2-TZVP basis set. For Zr, a relativistic effective core potential of 28 electrons was used for description of the core electrons. Polarizable continuum model calculations were employed by the integral equation formalism variant (IEFPCM).22 Stationary points were confirmed as minima or transition structures by harmonic vibrational frequency calculations using Gaussian 16. Quasi-harmonic corrections to the entropy 18a and enthalpy 18b employed a cut-off frequency of 100 cm -1 and the reduced translational entropy in solution was calculated by the method described by Whitesides and co-workers. All corrections were implemented using the Goodvibes script. A molarity of 9.40 M and a molecular volume of 138.4 Å 3 were used for toluene.