Asymmetric Transformations Using Resin-Bound Chiral Catalysts and Auxiliaries

3 ASYMMETRIC TRANSFORMATIONS USING RESIN-BOUND CHIRAL CATALYSTS AND AUXILIARIES 

In another approach, a chiral auxiliary can be fixed to solid-supported substrate and help direct the stereoselectivity of the asymmetric reactions to provide enantiopure molecules. In this chapter, we present some representative examples of resin-bound catalysts and chiral auxiliaries in asymmetric synthesis. For detailed reviews about the polymer-bound chiral ligands used in conjunction with metals and metalloids in asymmetric catalysis, chiral organic catalysts attached to polymer supports, and chiral auxiliaries on solid support, readers are referred to Refs 6 and 7. 

1 Catalytic Asymmetric Synthesis with Resin-Bound Chirai Cataiysts 

The asymmetric transformation for aldol reaction was carried out for the reactions of benzaldehyde and 4-nitrobenzaldehyde with acetone in the presence of dendritic and 

93-99%. Again, in this case too, the catalysts employed could be recycled several times without any loss of activity. 

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