Synthesis of chiral functionalized UiO-66-NH2@SiO2 and use of its domain-limiting effect for separating small enantiomers.

Abstract

Herein, to overcome the challenges of enantiomerically separating small chiral molecules, UiO-66-NH2@SiO2 was synthesized and samples of it were functionalized using a simple post-synthetic modification strategy with (+)-diacetyl-L-tartaric anhydride (DATA) and dibenzoyl-(+)-tartaric acid (DBTA), respectively. Then, based on the domain-limiting effect from the regular micropore structure of the included metal organic frameworks, the obtained UiO-66-DATA@SiO2 and UiO-66-DBTA@SiO2 each exhibited enhanced stereoselectivity for small enantiomers and successfully achieved the separation of α-amino acid and small alkaline enantiomers. This study has provided a new concept for the design and synthesis of chiral materials for separating small-molecule enantiomers.