基于氟固萃取回收技术的氮杂卡宾金属络合物催化不对称反应研究

传统的手性氮杂卡宾金属络合物催化剂存在价格昂贵、用量大及不易回收的缺点。本项目拟应用氟固萃取技术，设计和制备一类新型氟标记手性氮杂卡宾金属络合物，实现在不对称合成中催化剂应用及其回收利用，为绿色不对称催化过程提供新的途径。主要研究内容包括：（1）制备具有不同手性中心的氟标记手性氮杂卡宾金属络合物催化剂，进行结构修饰，建立有效的合成方法和氟标记手段；（2）研究氟标记催化剂的不对称催化性能，确定催化剂结构、"氟尾"性质、配体等对催化剂活性和对映选择性的影响，总结结构与性能之间的关系；（3）系统研究氟固相萃取中的构效关系，建立一套比较完整的利用氟固相萃取技术回收氟标记手性氮杂卡宾金属络合物催化剂的方法。该项目的顺利实施，将无疑是对绿色不对称催化研究的重要发展和补充。

Traditional N-heterocyclic carbene metal complexes have drawbacks of high cost, high catalyst loading and difficult for recovery. Proposed in this project is the design and development of a new fluorous chiral N-heterocyclic carbene metal complexes, their application for asymmetric catalysis, and fluorous solid-phase extraction (F-SPE) for catalyst recovery. The specific aims are: (1) design and synthesis of fluorous-tagged chiral N-heterocyclic carbene metal complexes with different chiral centers, and development of efficient methods for attaching of fluorous tags; (2) investigation of the catalytic activity and enantioselectivity of fluorous chiral N-heterocyclic carbene metal complexes; find out the relationship between catalyst structure and their performance; (3) study the length and total fluorine content of fluorous tags for F-SPE recovery to develop an optimized and cost effective method for catalyst recovery. In a word, this ongoing study would be an important development and complement for the green asymmetric catalysis.