Laboratoire de Chimie des Substances Naturelles, Université de Limoges, 123 Avenue Albert Thomas, 87060 Limoges, France.
Carbohydr Res. 2012 Jul 15;356:247-51. doi: 10.1016/j.carres.2011.10.028. Epub 2011 Oct 25.
This work deals with a novel and simple approach of cellulose reticulation using the Huisgen 1,3-dipolar cycloaddition, also known as a 'click chemistry' reaction, catalysed by copper and developed by Sharpless. This reaction is carried out by the addition of a true alkyne and an azide to form a triazole ring connecting the two polysaccharide chains. The addition of two different functions will allow us to control the crosslinking reaction, to avoid intra-chain reactions and thus to promote the creation of an enhanced three-dimensional network. Azidodeoxycellulose was obtained with a DS of 1.5 from tosyl cellulose. The propargylation reaction in aqueous media leading to propargylcellulose with a DS of 1.3. CuAAC reaction was performed between azidodeoxycellulose and propargylcellulose in a DMSO/H(2)O system using CuSO(4), 5H(2)O/sodium ascorbate as catalytic system. The modified cellulose products were analysed by infrared, NMR and X-ray photoelectron spectroscopies and resulting material was analysed using scanning electron microscopy (SEM).
这项工作涉及使用 Huisgen 1,3-偶极环加成反应(也称为“点击化学”反应)对纤维素进行新型简单的交联处理,该反应由 Sharpless 开发并由铜催化。该反应通过添加真正的炔烃和叠氮化物形成连接两个多糖链的三唑环来进行。添加两种不同的官能团将允许我们控制交联反应,避免链内反应,从而促进增强的三维网络的形成。从对甲苯磺酰纤维素获得取代度为 1.5 的叠氮纤维素。在水介质中进行炔丙基化反应,得到取代度为 1.3 的炔丙基纤维素。在 DMSO/H2O 体系中,使用 CuSO4、5H2O/抗坏血酸钠作为催化体系,在叠氮纤维素和炔丙基纤维素之间进行 CuAAC 反应。通过红外、NMR 和 X 射线光电子能谱分析改性纤维素产物,并用扫描电子显微镜(SEM)分析所得材料。