Functionalized Chitosan as a Green, Recyclable, Biopolymer‐Supported Catalyst for the [3+2] Huisgen Cycloaddition

Abstract

Clean and green: Copper(I) complexes of phenanthroline‐based ligands anchored on the chitosan polymer are good catalysts for the “click” cycloaddition of azides with terminal alkynes (see scheme; the scanning electron microscopy image shows the porous structure of the catalyst). These heterogeneous catalytic systems do not require a base or reducing agent and operate in alcohol or water.

Ionic Liquids: The Synergistic Catalytic Effect in the Synthesis of Cyclic Carbonates

“…Chitosan (CS), one of the most abundant natural biopolymers with many -OH groups, was used to synthesize chemically supported ILS catalysts [84,[99][100][101][102][103][104]. A series of CS chemically supported 1-ethyl-3-methyl imidazolium halide catalysts (CS- [EMIm][X], X = Cl, Br) were investigated for the synthesis of cyclic carbonates [105].…”

Porous polymer particles—A comprehensive guide to synthesis, characterization, functionalization and applications

“…On the other hand, non-ionic porous resins are also used in catalysis [403][404]. The catalyst is either a covalently attached organic molecule [405] or a metal that is chelated to the resin thanks to the electron donating ligands [406][407][408][409][410]. Simple precipitation of the metal to the pores is also reported [411][412].…”

Chitosan as a Natural Polymer for Heterogeneous Catalysts Support: A Short Review on Its Applications

“…Chitosan exhibits great potential in chemical applications and is commonly used as a catalyst supporters to promote the efficiency of chemical reactions [5,18]. The presence of readily functionalizable hydroxyl and amino groups on the chitosan and its insolubility in organic solvents make it very attractive in the application [19,20]. Besides, chitosan can be easily modified chemically or physically to become a versatile supporting material [21].…”