摘要 (硫)脲、亲核活化基与辅助基构成的手性双功能(硫)脲催化剂, 具有易于调控的结构和优异的催化性能, 因而, 双功能(硫)脲催化成为目前不对称有机催化的一个重要研究领域. 各类活化基的引入显著影响了该类催化剂的催化性能, 成为催化剂设计的主要考虑方向, 获得了广泛关注. 此外, 合适辅助基的引入也可调控与优化催化性能, 成为催化剂设计的一个重要补充方法. 然而, 到目前为止尚没有利用辅助基策略构建双功能(硫)脲催化剂的系统的综述. 从非手性辅助基与手性辅助基角度综述了双功能(硫)脲催化剂的设计与构建以及这些催化剂在系列不对称有机催化研究中的应用, 阐述了辅助基结构中的位阻、手性环境、电子效应、氢键给体等因素对催化性能的影响作用, 并对其今后的发展进行了展望. |
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Abstract：Chiral bifunctional (thio)ureas, which are made up of (thio)urea group, nucleophilic activation group and auxiliary, have attracted widespread attention in asymmetric organocatalysis research nowadays because of their easy control structure and excellent catalytic performance. The introduction of the activation group, which can greatly influence the catalytic performance of the catalyst, has become an important and concern research field for the catalyst design, while the introduction of suitable auxiliary can also be used to control and optimize catalytic performance, and become an important supplementary method. However, up to now, there is no systematical review exclusively on utilization of auxiliary strategy for the construction of chiral bifunctional (thio)ureas. In this paper, the research progress of the construction of chiral bifunctional (thio)ureas based on tunable achiral and chiral auxiliaries in recent years is reviewed. These catalysts can be successfully applied in a diverse variety of highly enantioselective transformations providing a wide range of versatile organic compounds. The influence of several factors in the auxiliaries, such as steric hindrance, chiral environment, electronic effect and hydrogen bond donor, on the catalytic performance is described. Besides, an outlook for future development of auxiliaries to construct bifunctional (thio)ureas is given. |