一种支持的,可切换和可回收的化催化剂
A J Sandee1, J N Reek, P C Kamer
1Institute of Molecular Chemistry, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands.
Journal of the American Chemical Society
|August 30, 2001
概括
这项研究在多酸盐支上固定了化催化剂,实现了对线性化的高选择性. 该系统可以在化,化和组合序列之间进行可逆切换,以实现高效的化学转换.
科学领域:
- 不同质的催化剂.
- 有机金属化学 有机金属化学
- 材料科学是一种材料科学.
背景情况:
- 均的水合成型催化剂具有高选择性,但存在分离困难.
- 将过渡金属复合物固定在固体支上是将同质催化剂优势与异质系统优势相结合的关键策略.
- 开发强大且可回收的催化系统对于可持续的化学合成至关重要.
研究的目的:
- 将一个同质的水合甲基化催化剂与多酸盐支器共振地结合起来,以提高可回收性和选择性.
- 为了研究固定复合物的催化性能在化和化反应中.
- 通过调整反应条件,探索切换催化系统在不同反应模式 (化,化,合) 之间的可能性.
主要方法:
- 通过sol-gel工艺制备固定催化剂,并将-素复合物与二氧化进行共价定.
- 使用固态NMR (31P,29Si MAS NMR),FT-IR和X射线光电子光谱学进行固定催化剂的表征.
- 在各种条件下 (CO/H2,单独的H2,醇的存在) 评估1 octene的化和化中的催化活性和选择性.
主要成果:
- 固定催化剂对线性化物 (94.6%) 具有很高的选择性,线性与分支的比率为65.
- 作为一种二次产物,化物到1-nonanol的意外化发生了.
- 该系统表现出可调节的行为,作为选择性基化催化剂 (X),化催化剂 (Y) 或双重基化/化催化剂 (Z),具有可逆切换和保留性能.
结论:
- 将复合物的共价固定在多酸盐支上,产生一种高度选择性和可回收的甲基化催化剂.
- 固定系统提供了前所未有的控制,允许通过简单地操纵反应条件,在不同的催化模式 (化,化,合) 之间进行可逆切换.
- 这种多功能催化系统为从基中选择性合成化物和酒精提供了可持续的方法.
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