A Pd(II)‐Functionalized Covalent Organic Framework for Catalytic Conjugate Additions of Arylboronic Acids to β,β‐Disubstituted Enones

Abstract

Abstract A palladium(II)‐functionalized covalent organic framework (Pd@TpBpy COF) constructed from 1,3,5‐triformylphloroglucinol (Tp) and [2,2′‐bipyridine]‐5,5′‐diamine (Bpy) is reported as a recyclable catalyst for conjugate additions in aqueous media. Additions of an array of stereoelectronically diverse arylboronic acid nucleophiles to β,β‐disubstituted enones form a variety of ketones containing benzylic all‐carbon quaternary centers in up to 92 % isolated yield. Studies on the recyclability of Pd@TpBpy COF show this catalyst remains active through at least 7 cycles and shows superior stability to related MOF catalysts with bipyridine linker units.