Construction of the Copper‐Functionalized Covalent Organic Framework Used as a Heterogeneous Catalyst for Click Reaction

Functional modification of the covalent organic frameworks (COFs) has become an efficient strategy to expand its applications in various fields. In this investigation, an imine linked T−D COF has been synthesized via solvothermal method using 2,4,6‐tris(4‐aminophenyl)pyridine (TAPP) and 2,6‐dihydroxynaphthalene‐1,5‐dicarbaldehyde (DHNDA) as building blocks. While synthesizing T‐D COF, hydroxyl groups are strategically introduced to the adjacent sites of −C=N− bonds in the framework. Such a special structure enables a strong coordination between the loaded copper metal ion and the hydroxyl groups together with imine bounds in the COF layered structure. The obtained copper‐containing COF, (Cu@T−D COF) hybrid material was used as an efficient heterogeneous catalyst for the alkyne‐azide click chemistry reactions and showed excellent catalytic activity in methanol/water medium. Furthermore, this Cu@T−D COF is stable and easily recycled and reused without loss of its catalytic activity. A highly efficient heterogeneous catalyst Cu@T−D COF was synthesized by strategic introduction of Cu(II) into the layer structure of T−D COF with functional hydroxyl groups and imine bounds, which exhibited excellent catalytic performance for click reaction of alkyne‐benzyl azide by combination of co‐catalyst of sodium ascorbate (NaAsc). In addition, the catalyst can be reused for at least four cycles without any change in catalytic activity.