One-Pot Synthesis of Deep Eutectic Solvents Containing Three-Dimensional Polymeric Materials with Excellent Catalytic Activity in the Knoevenagel Condensation Reaction

Abstract

Deep eutectic solvents (DESs)-containing three-dimensional (3D) porous organic polymers (termed TAM-BPA-ChCl/Ur, TAM-BPA-ChCl/Gly, and TAM-BPA-Bu4NBr/Im) were obtained via one-pot synthesis by using DESs as green reaction solvents for the first time. The DESs were confined into 3D extended structures during the synthetic process, as revealed by a series of techniques. The DESs-loaded polymeric materials were used to catalyze the Knoevenagel condensation of aldehydes and malononitrile and produced excellent yields at room temperature. As a typical example, the TAM-BPA-ChCl/Ur sample as a heterogeneous catalyst can be recovered easily and shows stable catalytic activity. This research presents a feasible method to prepare functional complex materials involving DESs and porous polymers.