在基催化剂组合物上的糖寡合化
Nina V Vlasenko1, Olena I Yanushevska2, Olga Z Didenko1
1LV Pysarzhevskii Institute of Physical Chemistry, National Academy of Sciences of Ukraine, Prosp. Nauky 31, 03028, Kyiv, Ukraine.
Chemistry (Weinheim an der Bergstrasse, Germany)
|November 14, 2023
概括
硫酸 (TiO2-S) 有效地催化糖醇寡合,形成各种糖化物. 然而,添加碳纳米管降低了转化,但增强了对短链甘油的选择性.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 糖的寡合化对于生产有价值的化学物质至关重要.
- 基于二氧化 (TiO2) 的材料被探索为潜在的催化剂.
- 了解催化剂修饰对糖醇转化的影响是必不可少的.
研究的目的:
- 研究基于TiO2的催化剂,包括硫酸和含碳纳米管的复合材料,用于糖的寡合化.
- 评估硫和碳纳米管修饰对TiO2酸和催化性能的影响.
- 为了阐明这些催化剂上糖醇激活的机制.
主要方法:
- 合成和表征TiO2,硫化TiO2 (TiO2-S) 和TiO2-碳纳米管复合材料.
- 使用这些催化剂进行了甘油寡合化反应.
- 减弱总反射率里埃变换红外光谱法 (ATR-FTIR) 用于研究糖醇激活.
主要成果:
- 只有硫酸 (TiO2-S) 显示出显著的活性,由于强大的基位,达到高达58.7%的糖醇转化.
- TiO2-S催化了糖的形成,形成具有线性和非线性结构的五糖.
- 将碳纳米管纳入催化剂减少了甘转化 (至10.5%),但缩小了产品谱,增加了短链甘的选择性 (72%的二甲甘,21%的三甲甘) 并仅形成线性结构.
结论:
- 硫酸是糖寡合化的有效催化剂,产生一系列的糖.
- 碳纳米管的添加改变了对短链,线性甘的选择性,但减少了整体转化.
- 硫酸的强基位的存在是其在糖寡合化中的催化活性的关键.
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