Functionalized Chitosan as a Green, Recyclable, Biopolymer-Supported Catalyst for the [3+2] Huisgen Cycloaddition
Functionalized Chitosan as a Green, Recyclable, Biopolymer-Supported Catalyst for the [3+2] Huisgen Cycloaddition
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DOI：
10.1002/anie.200901309
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发表时间：
2009-01-01
影响因子：
16.6
通讯作者：
Taran, Frederic
中科院分区：
文献类型：
--
作者：
Chtchigrovsky, Melanie;Primo, Ana;Taran, Frederic
Owing to increasing concern about environmental impact, tremendous effort has been made towards the development of new processes that minimize pollution in chemical synthesis. For this reason and others (catalyst removal, recovery, and recycling), heterogeneous catalysis is clearly on the rise, including in industry.[1] Of the many systems that have been developed over the past decades, metallic species supported on inorganic materials (eg SiO2, Al2O3) or on charcoal are the most common.[2] The immobilization of transition metals on polymer supports derived from petrochemicals (eg polystyrenes) has also been the focus of many efforts.[3] Recent developments for cleaner, sustainable chemistry are being driven by a shift from petrochemical-based feedstocks to biological materials. There is considerable interest in exploiting natural polymer macrostructures, and in particular those of polysaccharides, to create high-performance and environmentally friendly catalysts. Indeed, polysaccharides present many advantages that may stimulate their use as polymeric supports for catalysis: 1) They are present in enormous quantity on earth, 2) they contain many functionalities that can be used readily for the anchoring of organometallic species, 3) they contain many stereogenic centers, and 4) they are chemically stable but biodegradable.[4] Surprisingly, although there has been a worldwide realization that nature-derived polysaccharides can provide the raw materials needed for the production of numerous industrial consumer goods, their use as supports for catalysis is still in its infancy.Chitosan (Figure 1A) is a particularly attractive polysaccharide for application in catalysis [5] owing to the presence of readily functionalizable amino groups and its insolubility in organic solvents. A copolymer of β (1! 4)-2-amino-2-deoxyd-glucopyranose and 2-acetamido-2-deoxy-d-glucopyranose,
