Optimization of catalyst enantioselectivity and activity using achiral and meso ligands.

摘要: The optimization of asymmetric catalysts for enantioselective synthesis has conventionally revolved around the and screening enantiopure ligands. In contrast, we have optimized an reaction by modification a series achiral Thus, employing (S)-3,3‘-diphenyl BINOL [(S)-Ph2-BINOL] diimine diamine activators in addition alkyl groups to benzaldehyde, observed enantiomeric excesses between 96% (R) 75% (S) 1-phenyl-1-propanol. Some ligands examined low-energy chiral conformations that can contribute environment catalyst. These include with meso backbones adopt conformations, become axially on coordination metal centers, form stereocenters pendant conformations. Additio...