Incorporation of Ir(C^N)2(N^N)-NiCl2 in a (N^N)-covalent organic framework for transcendent dual catalysis in photochemical cross-coupling synthesis

Abstract

A quinoline-based covalent organic framework (N^N)-Q-COF was constructed with chemically stable networks and (N^N)-sites. Its coordination bond with Ir(C^N)₂(N^N) units generated new entities with exciting photophysical properties; particularly, the incorporation of a coumarin ligand greatly elevated its properties to a higher level. The further anchoring of NiCl₂ produced structures merging both photoredox and organometallic catalysts, resulting in excellent photocatalytic activities in C–S and C–N cross-coupling synthesis. The organic integration of Ir(C^N)₂(N^N), NiCl₂, and COFs and the advantages of COF networks were responsible for this transcendent dual catalysis. The chemical stability of Q-COFs and the coordination anchoring of Ir(C^N)₂(N^N) and NiCl₂ enabled its recycling and reuse with no reduction in catalytic performance.