Covalent organic framework supported Pd(II)‐catalyzed conjugate additions of arylboronic acids to α,β‐unsaturated carboxylic acids

A palladium(II)‐coordinated covalent organic framework (Pd(II)@COF) was mechanochemically synthesized from [2,2′‐bipyridine]‐5,5′‐diamine (Bpy) and 1,3,5‐triformylphloroglucinol (Tp), which was demonstrated as a catalyst for conjugate addition of arylboronic acids to unreactive α,β‐unsaturated carboxylic acids in aqueous media (water/acetone = 1:1). Modest to good yields were obtained for most substrates, and studies on the catalyst recyclability showed that the heterogeneous catalyst gave >80% yields in the first 4 cycles. This research broadens the application of COFs supported catalysis and gave a new option for Pd(II)‐catalysis.