新型手性卡宾烯烃配体在不对称烯烃复分解反应中的应用

Olefin metathesis is one of the most important reactions to construct carbon-carbon double bonds. In contrast to the great progress being achieved in this area, asymmetric olefin metathesis is still less developed. Some important issues await to be resolved, such as the sensitity of Mo-based catalyst to moisture and oxygen, the high catalyst loadings of Ru-based catalysts, the distinct substrate-to-catalyst dependency, the limited quantity of Ru-based catalyst and so on. So design and synthesis of novel catalysts is an extremely important direction in asymmetric olefin metathesis research. The applier envisage to combine carbene moiety and olefin moiety together skillfully, to design and synthesis a novel type of chiral carbene-olefin ligands. We will apply the Ru-complex of the novel ligand in asymmetric ring-closing metathesis, to find out the influence on the catalyst to the reactivity and enantioselectivity, in order to further modifying the structure of the ligands to find an excellent catalytic system. Then the catalyst will be applied in asymmetric ring-opening cross-metathesis and asymmetric cross-metathesis, aiming to expanding the types of asymmetric olefin metathesis reactions and the scopes of the substrates, reducing the catalyst loadings, and developing a highly efficient and highly enantioselective catalytic system. This program is of great importance in solving the great issues in asymmetric olefin metathesis reactions, and developing novel chiral carbene-olefin ligands with the independent intellectual property.

烯烃复分解反应是一类构建碳碳双键的重要反应，尽管已经取得了令人瞩目的成就，但不对称烯烃复分解反应仍面临很多问题亟待解决，如目前两类催化剂中，钼催化剂对水和空气比较敏感，而钌催化剂用量较大，底物的适用性差，催化剂种类数量有限等。因此新型催化剂的设计合成是不对称烯烃复分解反应研究及其重要的研究方向。申请人拟将卡宾单元与烯烃单元进行巧妙结合，设计、合成一类新型的手性卡宾烯烃配体，通过研究其与钌形成的络合物在不对称的关环复分解反应中的应用，考察催化剂对反应活性和对映选择性的影响，从而对配体结构进行进一步的调整，以期发展优秀的催化剂体系，并将其应用于开环-交换烯烃复分解反应和不对称交换复分解反应，拓展不对称烯烃复分解反应的反应类型以及底物的适用性，降低催化剂用量，发展高效高选择性的催化体系。该项目对于解决不对称烯烃复分解反应中的重要科学问题，开发具有自主知识产权的手性配体及催化剂具有重要的科学意义。