可内部修饰的超分子仿生催化剂的构筑及其在有机合成中的应用

Chemists have been inspired by natural enzymes since their discovery. Supramolecular structures offer one way to mimic the basic working principle of enzymes due to their ability to encapsulate and stabilize guest molecules. Although studies using supramolecular structures as the catalysts are receiving increasing attention in recent years, supramolecular catalysis has not been widely used in organic synthesis as small-molecule catalysis. One of the most important reasons is that the construction of catalytically active supramolecular structures is still challenging. In this proposal, we will synthesize supramolecular cages featuring endohedral functional groups, which will be modified after the construction of the supramolecular structures. By applying the post-assembly modification strategy, we aim at two applications of the supramolecular structures constructed. For structures already possessing catalytic center, the cavity will be tailored to adapt suitable substrates by modifying the endohedral moieties. The preferential binding of certain substrate is expected to be translated into selectivity based on recognition of the substrate configuration. In other cases, catalytic active functional groups will be installed within the cavity via the modification of endohedral functional groups. This may provide a new way to combine supramolecular catalysis and small-molecule catalysis and will be used to construct molecular factory resembling multi-enzymatic systems. By performing the research proposed above, we may establish a new method to construct supramolecular catalysts and may provide new solutions to address the selectivity and efficiency issues encountered in organic synthesis.

超分子结构由于其包覆和稳定客体分子的能力被科学家们视为天然酶的潜在模拟物。近年来，虽然以超分子结构作为催化剂的研究受到了越来越多的关注，超分子催化却并未像小分子催化一样被广泛地运用到有机合成中。最重要的原因之一就是构筑具有催化活性的超分子结构仍具有较大的挑战性。本研究拟构建具有内部活性官能团的超分子结构作为平台，通过对超分子结构腔体的模块化修饰开展两方面的研究：一、通过对超分子催化剂腔体形状或大小的调控使其适应不同的底物，发展基于构型识别的选择性反应模式；二、通过在超分子结构的腔体内引入具有催化活性的基团，探索将超分子催化和小分子催化结合的新模式，并将所得的新型超分子催化剂用于构建类似天然多酶体系的连续反应“分子工厂”。通过上述的研究，我们有望发展一类具有一定普遍适用性的构筑超分子催化剂的新模式，为有机合成的选择性和效率问题提供新的解决方案。

超分子结构由于其包覆和稳定客体分子的能力被科学家们视为天然酶的潜在模拟物。近年来，虽然以超分子结构作为催化剂的研究受到了越来越多的关注，超分子催化却并未像小分子催化一样被广泛地运用到有机合成中。最重要的原因之一就是构筑具有催化活性的超分子结构仍具有较大的挑战性。天然酶的催化活性源于其腔体内大量的活性氨基酸残基。因此，在超分子结构的内部引入具有催化活性的基团是构建超分子仿生催化剂的关键。本研究以发展一种具有普适性的构建超分子仿生催化剂的策略为研究目标，开展了以下三方面的研究：（1）[Pd2(LA)2(LB)(LC)]型杂配体超分子笼的精准合成；（2）[Pd2(LA)2(LB)(LC)]型杂配体超分子笼的位点选择性内官能化；（3）内官能化杂配体超分子笼的初步主客体化学研究。通过上述研究，我们发展了一种“自下而上”地构建内官能化超分子主体结构的新方法，为仿生超分子催化剂的构建提供了一种具有一定普适性的新策略。. 在本项目的资助下，项目负责人作为通讯作者将研究成果发表于Angew. Chem. Int. Ed.期刊。培养博士生3名，硕士生2名。