基于优势手性片段策略的配体设计及在烯烃不对称氢芳基化反应和聚合反应中的应用

Asymmetric catalysis has become extremely important as the demand for multi-level chiral compounds, including chiral small molecules and chiral polymers, has increasingly grown. Although asymmetric catalysis has been developed for nearly 50 years, the number of privileged chiral ligands is limited, especially the strategies for designing chiral ligands are very few, and new strategies need to be developed. Meanwhile，as energy crisis and environment protection become principal concerns, it’s of great significance to develop new strategies to convert abundant feedstocks from fossil resources and biomass sources (such as olefins and aromatics) to high value chiral products without by-products. Metal-catalyzed asymmetric hydroarylation and polyhydroarylation of simple olefins based on aromatic C-H activation are ideal reactions, since it’s free of byproducts and has 100% atom-economy, excellent step-economy and redox-economy. The asymmetric hydroarylation reactions developed to date, however, are limited to special substrates. Moreover, the selectivity of the reactions is moderate, and the corresponding asymmetric copolymerization is unknown. This project will focus on the core scientific issues of the precise construction of optically active molecules. Through the development of a new strategy for ligand design based on privileged chiral fragment approach, we aim to develop a series of new privileged chiral ligands, expand the substrate scope and improve the regioselectivity and stereoselectivity for asymmetric hydroarylation and polymerization of olefins, and eventually to provide an efficient and practical strategy for the precise construction of multi-level chiral materials.

随着人们对多层次手性物质(包括手性小分子和手性聚合物等)需求的日益增长，不对称催化变得愈发重要。虽然不对称催化已经发展了近五十年，但是优势手性配体数量有限，尤其是设计手性配体的策略很少，有待发展新策略。同时，由于能源、环境问题的日益严峻，对化石资源和生物质来源的廉价大宗原料(例如烯烃和芳烃)进行无副产物的高效不对称转化，具有重要意义。基于芳烃C-H活化的简单烯烃的不对称氢芳基化反应和聚合反应，则是实现化工原料高附加值化的理想反应。但是，目前该类反应底物范围极其有限、选择性不高，不对称聚合的例子还未见报道。本项目将针对单一镜像异构体的精准构筑这一核心科学问题，发展基于优势手性片段的配体设计新策略，合成系列新型优势手性配体，应用于烯烃的不对称氢芳基化反应和聚合反应的研究，希望实现底物范围的拓展和区域、立体选择性的有效控制，为多层次手性物质的精准构筑提供高效、经济的新策略。

本项目针对单一镜像异构体的精准构筑这一核心科学问题，提出了基于优势手性片段的配体设计新策略，发展了ANIPE和SIPE类新型优势氮杂环卡宾配体，实现了3类金属卡宾催化的烯烃分子内不对称氢芳基化反应、2类分子间烯烃氢芳基化反应、3类简单原料（包括酮、芳基卤代物和胺等）的不对称芳基化反应，高效高选择性合成了手性吡啶、多氟芳烃、叔醇、苯胺和联芳基等化合物；基于发展的新卡宾配体和催化体系，实现了3类镍催化的聚合反应，创制了手性聚叔醇、含氟无支化聚合物和含氟共轭聚合物。研究从配体设计新策略的发展，到新型手性卡宾配体的设计和在多类氢芳基化和芳基化反应中的应用，最后结合金属卡宾催化和高分子合成，实现了多层次手性物质（包括小分子和高分子）的高效高选择性合成。项目取得了系列原创成果，实现了研究目标。所发展的配体设计新策略和新配体，将可能为手性物质科学的发展做出进一步贡献。项目共发表论文21篇（包括J. Am. Chem. Soc. 4篇和Angew. Chem. Int. Ed. 3篇），申请中国发明专利2件，申请PCT1件，培养研究生9名，完成了预定研究任务。