Porous aromatic framework (PAF-1) as hyperstable platform for enantioselective organocatalysis

High density of phenyl rings makes PAF-1 have robust structure and highly lipophilic pore, which make it very suitable for organocatalysis. However, there is no report about using PAF-1 as platform for enantioselective organocatalysis. In this paper, using PAF-1 as the platform, a chiral prolinamide catalytic site was introduced onto the framework of PAF-1 via a series of stepwise post-synthetic modifications, obtaining a novel PAF-supported chiral catalyst named PAF-1-NHPro. Then its enantioselective catalytic performance was studied by subjecting it to catalyze the model Aldol reaction between p-nitrobenzaldehyde and cyclohexanone. PAF-1-NHPro showed good diastereoselectivity and enantioselectivity with excellent and easy recyclability.