功能化氨基和二醇的连续化学选择性甲基化与超临界甲醇在固体酸和酸双功能催化剂上
Tomoharu Oku1, Yoshitaka Arita, Hideaki Tsuneki
1Graduate School of Science and Engineering and Frontier Collaborative Research Center Tokyo Institute of Technology and Joint Research Center for Supercritical Fluids, Japan Chemical Innovation Institute, O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
Journal of the American Chemical Society
|June 10, 2004
概括
超临界甲醇 (scCH(3) OH) 能够在固体催化剂上进行高度选择性的氨基酸甲基化. 一种Cs-P-Si混合氧化物催化剂实现了94%的N-甲基化选择性,证明了甲基化化合物的高效合成.
科学领域:
- 催化剂是一种催化剂.
- 化学工程是化学工程的重要组成部分.
- 有机合成 有机合成
背景情况:
- 选择性N-甲基化对于合成有价值的有机化合物至关重要.
- 超临界流体为增强的化学过程提供独特的反应环境.
研究的目的:
- 通过使用超临界甲醇 (scCH(3) OH) 来研究双功能胺的选择性N-甲基化.
- 在这个反应中评估各种固体酸和双功能催化剂的性能.
- 识别最有效的催化剂并了解反应机制.
主要方法:
- 使用超临界甲醇的连续流量,固定床反应堆实验.
- 常规固体酸 (H-mordenite,β-zeolite,无形-) 和双功能催化剂 (Cs-P-Si混合氧化物,-) 的测试.
- 使用神奇角度旋转NMR光谱和X射线衍射对Cs-P-Si催化剂的表征.
主要成果:
- 与传统方法相比,超临界甲醇显著提高了N-甲基化化学选择性.
- Cs-P-Si混合氧化物催化剂表现出卓越的性能,达到94%的N-甲基化选择性,在300°C和8.2MPa时的86%转换.
- 催化剂在合成N-甲基化氨基醇,二胺和O-甲基化乙烯糖醇方面表现出成功的应用.
- 氨基醇中的基团被发现对高反应性和选择性至关重要,这是由于潜在的绑定效应.
结论:
- Cs-P-Si混合氧化物催化剂,其弱酸配对位点,对于选择性脱水N-甲基化非常有效.
- 超临界甲醇是有效和选择性甲基化反应的有希望的介质.
- 反应物的结构特征,特别是基团的存在,在催化性能中起着重要作用.
相关概念视频
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