Development of a novel Bronsted acid UiO-66 metal-organic framework catalyst by postsynthetic modification and its application in catalysis

A novel Bronsted acid derived metal-organic framework (MOF) has been developed to serve as an efficient heterogeneous catalyst for the acetalization and Morita-Baylis-Hillman reaction. Aromatic sulfonic acid groups were successfully incorporated to the framework of UiO-66 by post-synthetic modifications using commercially available anhydridic reagents. The UiO-66-RArSO3H Bronsted acid catalyst was fully characterized using SEM, PXRD, FTIR, TGA and N-2 adsorption/desorption isotherms. Furthermore, efficient acetalization and Morita-Baylis-Hillman reactions were evaluated to demonstrate the high catalytic performance of the UiO-66-RArSO3H catalyst. The UiO-66-RArSO3H catalyst is compatible with a variety of substituted substrates and can be recycled five times without a compromise in the yield or selectivity.