Table 1.
Relative electronic and free energies (in kcal mol−1) of the cinchona alkaloid conformers determined from gas phase static computations or from the REMD simulations (DFTB3/3OB‐UFF) at 300 K. The geometries for computing the static DFTB3 energies are optimized at the same DFTB3 level. The BP86‐D results are taken from Ref. [132].
| DFTB3/3OB‐UFF | BP86‐D/TZP132 | ||
|---|---|---|---|
| (Static) Electronic energy | REMD free energy | Static free energy | |
| Anti‐open (1) | 1.3 | 0.00 | 0.6 |
| Syn‐open (4) | 0.0 | 1.57 | 0.0 |
| Anti‐closed (2) | 6.5 | 2.11 | 5.4 |
| 3 | 1.7 | 1.94 | – |