Origin of (pi)-Facial Diastereoselection in Hydride Reduction of Piperidones. The Importance of Ground-State Effects

The exterior frontier orbital extension model (the EFOE Model) strongly suggested that the ground-state conformation (steric effects) and the anisotropic frontier orbital (LUMO) extension over (pi)-faces may be the origin of the (pi)-facial diastereoselection in hydride reductions of substituted piperidones.