Asymmetric Histidine-Catalyzed Cross-Aldol Reactions of Enolizable Aldehydes: Access to Defined Configured Quaternary Stereogenic Centers

摘要

Organocatalysis has emerged within the past decade as the third pillar of asymmetric catalysis in addition to metal and enzyme catalysis. Several long-standing problems of asymmetric aldol addition have been solved via organocatalysis. One important example is the direct catalytic asymmetric cross-aldol addition between enolizable aldehydes, which has been realized through the use of proline, derivatives of proline, and chiral imidazolidinones.