点击三唑桥连的N-杂环卡宾双金属化合物的合成及其催化性能

Due to excellent σ-donor properties, ease of synthesis, and variable steric bulk，N-heterocylic carbenes (NHCs) have become a very important class of ligands in organometallic chemistry and catalysis. Based on the rule of bimetallic cooperative action, we design and synthesis a series of triazole-bridged multi-dental N-heterocyclic carbene ligands. These ligands have been used for the modular preparation of a series of homo- and hetero-bimetallic N-heterocyclic carbene complexes. The obtained bimetallic N-heterocyclic carbene complexes have been used to test their catalytic activity on the one-pot tandem reaction of dihydroalkoxylation reaction, allylic alkylation/Pauson-Khand annulation reaction , and click/Sonogashira reaction. In the process, we studied the interrelation of molecule structure and metal-metal interaction and their influence on the catalytic performance. Moreover, we try to understand the cooperative action mechanism via separating and characterizing the reaction intermediate product and explore the structure-activity relationship. The implementation of this proposal will obtain a type of bimetallic catalyst of high activity, high selectivity, and stability.And a series of green organic synthesis method of one-pot tandem reaction will be established and developed. A new bimetallic synergetic catalysis model will be made up.This rerults have important scientific significance and great potential value in the field of organic synthesis.

本项目基于双金属协同催化的设计理念，从构造点击三唑桥连且具有强配位卡宾和弱配位氮、硫、膦或氧原子官能化的多齿N－杂环卡宾配体出发，设计合成具有金属-金属作用且性能稳定、活性高的双金属催化剂，构建点击三唑桥连的同核和异核双金属化合物的模板化制备技术，考察其对双氢化烷氧基化反应、烯丙基烷基化/Pauson-Khand反应和click/Sonogashira等一锅串联反应的催化活性，研究催化剂的结构和金属－金属间距对催化剂性能的影响，通过调变金属-金属间的距离和配体的结构，提高催化剂的活性及选择性，研究构效关系，探索反应机理。本项目的实施有望得到高活性、高选择性且稳定的双金属催化剂，建立和发展双氢烷基化反应、烯丙基烷基化/Pauson-Khand反应和click/Sonogashira一锅串联反应等绿色有机合成反应新方法，构建双金属协同催化模型,具有重要的科学意义和极大的潜在应用价值。

本项目围绕过渡金属氮杂环卡宾化合物的合成及其应用方面开展了工作，主要开展了以下几部分内容：（1）合成了一系列点击三唑官能化N－杂环卡宾配体前体即咪唑盐及其相应的银、铜、镍和铂氮杂环卡宾化合物，研究了多核铜卡宾化合物对叠氮化合物和炔类化合物间的环加成反应的催化作用，使用0.5mol%的双核铜化合物在室温下高效地实现环加成反应；发展了高效催化Suzuki偶联反应的三唑官能化非对称“NCN”钳型镍卡宾催化剂，通过调节配体的结构，制备了少见的羟基桥连的双核镍卡宾化合物，双核镍化合物具有较短的Ni-Ni距离，为研究双金属协同催化提供了新的模型；（2）设计并合成了两个异核多金属氮杂环卡宾Ag/Pt/Ag化合物，系统研究了其晶体结构和光物理化学性能，此类异核多金属的合成为制备自组装金属簇合物提供了新方法；（3）合成并结构表征了双酰胺官能化的双核镍和铜卡宾化合物；(4)在研究氮杂环卡宾和点击化学的基础上，研究了点击化学法在高分子材料改性的应用。