Organocatalytic chiral polymeric nanoparticles for asymmetric aldol reaction.

Chiral polymeric particles (CPPs) were studied extensively in recent years due to their importance in pharmaceutical applications. Here, nanosized CPPs were synthesized and applied as catalysts for direct asymmetric aldol reaction. The CPPs were prepared by miniemulsion or inverse miniemulsion based on various chiral amino acid derivatives and characterized by dynamic light scattering and scanning electron microscopy. The nanoparticles with spherical structure between 250 and 400 nm and high chiral surface area were used as catalysts in the aldol reaction at room temperature without additional solvent. l-tryptophan gave the highest enantiomeric excess, >86% with similar catalytic performance four times.