Table 3. Relative energies of the eight diastereomeric transition states for the benzoin condensation with catalyst 3.
Transition-state geometry* |
|||||
---|---|---|---|---|---|
Catalyst | Enolamine | Enolamine face | Aldehyde face | Product configuration | ΔGrel, kcal/mol† |
R | E | si | si [TS5]‡ | R | 0 |
R | E | si | re [TS6]‡ | S | 1.8 |
R | E | re | re | S | 4.9 |
R | Z | re | si | R | 7.3 |
R | Z | re | re | S | 7.9 |
R | E | re | si | R | 8.2 |
R | Z | si | si | R | 10.3 |
R | Z | si | re | S | 11.4 |
See Data Set 1 for figures of structures and Cartesian coordinates.
Relative energies obtained by single-point B3LYP/6-31G(d) calculations.
Depicted in Fig. 7.