Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, Centre of Excellence for Polysaccharide Research, Humboldtstraße 10, D-07743, Jena, Germany.
Laboratory of Fibre and Cellulose Technology, Åbo Akademi University, Porthansgatan 3, FI-20500, Turku, Finland.
Carbohydr Polym. 2018 Aug 1;193:45-53. doi: 10.1016/j.carbpol.2018.03.083. Epub 2018 Mar 26.
Xylan phenyl carbonate (XPC) derivatives were prepared and characterized comprehensively. By conversion of xylan with phenyl chloroformate either in dipolar aprotic solvents with LiCl or in an ionic liquid, XPC with degrees of substitution (DS) of up to 2.0, i.e., fully functionalized derivatives, could be obtained. The synthesis was studied with respect to the influence of different reaction parameters. It was found that the reaction medium as well as the type of starting xylan strongly affected the efficiency of the derivatization. The derivatives obtained were characterized by FT-IR- and NMR spectroscopy. Surprisingly, it was found that C-3 is the most reactive position in this particular reaction while substitution in position C-2 only occurred if the neighboring position C-3 already carried a phenyl carbonate group. XPC were found to form spherical nanoparticles (NP) of well-defined shape with diameters around 158 nm. These materials possess unique potential as activated NP for advanced applications.
木聚糖苯碳酸酯（XPC）衍生物被全面制备和表征。通过在有 LiCl 的偶极非质子溶剂中或在离子液体中用苯基氯甲酸酯对木聚糖进行转化，可以得到取代度（DS）高达 2.0，即完全官能化的衍生物。对不同反应参数的影响进行了合成研究。结果发现，反应介质以及起始木聚糖的类型强烈影响了衍生化的效率。通过傅里叶变换红外光谱（FT-IR）和核磁共振光谱（NMR）对得到的衍生物进行了表征。令人惊讶的是，发现 C-3 位是该特定反应中最具反应性的位置，而 C-2 位的取代仅在相邻的 C-3 位已经带有苯碳酸酯基团时才会发生。XPC 被发现形成具有约 158nm 直径的球形纳米粒子（NP），形状规则。这些材料作为用于高级应用的活化 NP 具有独特的潜力。
