上海交通大学崔勇团队报道了共轭聚合物中的同手性富π共价有机框架实现手性印迹——受限聚合和从头开始的手性记忆。相关研究成果发表在2024年3月20日出版的《德国应用化学》。

光学活性π-共轭聚合物（OACPs）因其与生物螺旋的相似性和有趣的手性相关功能，而引起了越来越多的研究兴趣。传统的合成方法包括，通过复杂的有机合成用对映体侧取代基修饰非手性共轭聚合物结构。

该文中，研究人员报道了一种新的方法：通过在2D或3D手性共价有机框架（CCOFs）的纳米孔内非手性单体的超分子限制聚合，模板合成未取代的OACPs。研究发现，类似于非酶聚合酶链式反应（PCR）系统，富含手性π的纳米空间促进了原位对映体特异性聚合和自增殖，从而产生手性印迹。

堆叠的聚合物链在动力学上是惰性的，足以在从CCOFs释放后，甚至在高达200℃的温度下处理后记忆手性信息。分离的OACPs表现出强大的对映体识别能力，在分离外消旋氨基酸方面实现了高达85%的ee。这突出了利用CCOFs作为模板将光学活性超分子印迹到CPs中的潜力，为OACPs的合成进化和高级功能探索铺平了道路。

附：英文原文

Title: Homochiral π-Rich Covalent Organic Frameworks Enabled Chirality Imprinting in Conjugated Polymers: Confined Polymerization and Chiral Memory from Scratch

Author: Xiaofeng Zhang, Xinfa Chen, Shiguo Fu, Ziping Cao, Wei Gong, Yan Liu, Yong Cui

Issue&Volume: 2024-03-20

Abstract: Optically active π-conjugated polymers (OACPs) have garnered increasing research interest for their resemblance to biological helices and intriguing chirality-related functions. Traditional methods for synthesizing involve decorating achiral conjugated polymer architectures with enantiopure side substituents through complex organic synthesis. Here, we report a new approach: the templated synthesis of unsubstituted OACPs via supramolecularly confined polymerizations of achiral monomers within nanopores of 2D or 3D chiral covalent organic frameworks (CCOFs). We show that the chiral π-rich nanospaces facilitate the in situ enantiospecific polymerization and self-propagation, akin to nonenzymatic polymerase chain reaction (PCR) system, resulting in chiral imprinting. The stacked polymer chains are kinetically inert enough to memorize the chiral information after liberating from CCOFs, and even after treatment at temperature up to 200 oC. The isolated OACPs demonstrate robust enantiodiscrimination, achieving up to 85% ee in separating racemic amino acids. This underscores the potential of utilizing CCOFs as templates for supramolecularly imprinting optical activity into CPs, paving the way for synthetic evolution and advanced functional exploration of OACPs.

DOI: 10.1002/anie.202403878

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202403878