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.