Asymmetric hetero Diels-Alder reaction catalyzed by chromium complexes of heterogeneously hybridized salen/salan ligands

Various heterogeneously or homogeneously hybridized salen/salan ligands were synthesized, and study of hetero Diels-Alder reactions using their chromium complexes as catalysts revealed that a well-designed heterogeneously hybridized ligand serves as a chiral auxiliary as efficiently as the homogeneously hybridized ligand and its chromium complex has high catalytic activity.