Click post-synthetic modification of metal-organic frameworks for asymmetric aldol catalysis

The reaction of dimethyl 5-(prop-2-ynyloxy)isophthalic acid, meso-alpha, and beta-di (4-pyridyl) glycol with ZnCl2 in a methanol aqueous solution affords MOF Zn-DPPG. The enantiomeric Zn-Fun1 and Zn-Fun2 were obtained through a strategy of in situ click reactions of Zn-DPPG with two opposite chiral adducts. With the L- or D-proline chiral functionality, the two Zn-Funs exhibited remarkable catalytic activities in the relative asymmetric aldol reactions, leading to the formation of opposite enantiomorphs, respectively. (C) 2013 Published by Elsevier B.V.