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

Abstract

Ein Biopolymer zur Unterstützung: An Chitosan verankerte Kupfer(I)‐Komplexe verschiedener Phenanthrolin‐Liganden sind gute Katalysatoren für die Cycloaddition von Aziden mit terminalen Alkinen (siehe Schema; das SEM‐Bild zeigt die poröse Struktur des Katalysators). Diese heterogenen Katalysesysteme benötigen weder Basen noch Reduktionsmittel und können in Alkohol oder Wasser effizient eingesetzt werden.

Copper(I) iodide supported on modified cellulose‐based nano‐magnetite composite as a biodegradable catalyst for the synthesis of 1,2,3‐triazoles

“…So, immobilization of catalysts on suitable insoluble supports is one of the most reliable methods for improving the efficiency and recovery of catalysts and strongly recommended from the viewpoint of green chemistry . Zeolites, montmorillonite, polystyrene, chitosan and modified KIT‐5 are some of the notable supports that bring about the heterogeneous catalysis of regioselective, three‐component reactions of alkyl halides, sodium azide and terminal alkynes.…”

Magnetically recoverable chitosan-stabilised copper–iron oxide nanocomposite material as an efficient heterogeneous catalyst for azide–alkyne cycloaddition reactions

“…sodium ascorbate) or added directly as cuprous salts, usually with stabilizing ligands. [17][18][19][20][21][22] Recently, functionalized magnetic nanoparticles represent as feasible alternatives to conventional materials as robust, easily available, high-surface-area heterogeneous catalyst supports. But these catalytic systems sometimes require oxidative agents.…”

Increased Catalytic Activity of Surface‐Immobilized Palladium Complexes in the Fluorogenic Deprotection of an Alloc‐Derivatized Coumarin

“…[24][25][26] This elegant approach affords a powerful tool for rapidly monitoring and optimizing reaction conditions. [27][28][29] Silicon surfaces were first modified with a terpyridine-attached triethoxysilane and subsequently immersed in a solution of Pd to afford the catalytic surfaces [Si-terpy-Pd]. Reaction of 4'-(4-anilino)-2,2':6',2''-terpyridine 3 [30] and 3-isocyanatopropyl triethoxysilane (ICTES) in THF at reflux in presence of a catalytic amount of Et 3 N (Scheme 2) lead to the formation of triethoxysilane 4. .…”