用于不对称的水合成型的固定 bisdiazaphospholane 催化剂
Tyler T Adint1, Clark R Landis
1Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison Wisconsin 53706, United States.
Journal of the American Chemical Society
|April 19, 2014
概括
由 bis-3,4-diazaphospholanes (BDPs) 衍生出的不移的不对称水合催化剂具有高选择性和活性,与同质催化剂相比. 这些可回收的催化剂在批量和流量系统中提供了极佳的性能,并且在批量和流量系统中出水量最小.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
背景情况:
- 同质催化剂具有很高的选择性,但存在分离挑战.
- 催化剂的固定对于可回收性和可持续性至关重要.
- 双-3,4-酸 (BDPs) 是在不对称催化中有效的配体.
研究的目的:
- 开发和评估固定不对称的甲基化 (iAHF) 催化剂.
- 为了比较固定BDP催化剂与其同质对应物的性能.
- 为了评估固定化化催化剂的可回收性和浸出性.
主要方法:
- 通过碳酸功能化,对乙烯酸 bis-3,4-diazaphospholanes (BDPs) 与珠子和二氧化支物的共价附着.
- 通过将绑定的BDP暴露在Rh ((acac) ((CO) 2.
- 在批量和流量条件下对亲基拉基的不对称基化中的催化剂性能评估.
主要成果:
- 在Tentagel树脂上的固定催化剂表现出高的区域选择性和反选择性,与同质催化剂相比.
- 经负载校正后,催化剂活性接近同质类型的催化剂活性.
- 在批量反应堆和流动反应堆中观察到出色的可回收性和最小的泄漏.
- 与结合的催化剂表现出降低的反选择性.
结论:
- 基于BDP的固定催化剂对不对称的水合甲基化有效,具有高选择性和活性.
- 触角支持的催化剂为同质系统提供了可回收和可持续的替代方案,最小的金属出.
- 对于支持的催化剂来说,需要进一步优化,以提高反选择性.
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