新加坡国立大学吴继善团队的一项最新研究利用Friedländer合成得到了1,6-蒽唑啉连接的π共轭大环和二维聚合物。2021年9月25日出版的《德国应用化学》杂志发表了这项成果。

该团队报道了一个通过酸介导的Friedländer合成的1,6-蒽唑啉(AZ)连接的晶体二维聚合物AZP 。研究人员首先通过两个模型反应验证了该方法的可行性，然后合成了三个AZ基大环MCn (n=5-7)，其中主要分离产物为六方MC6。有利的宏观循环形成在很大程度上可归因于Friedländer合成的动态特点，包括亚胺缩合和醛醇缩合。

通过实验和模拟，团队验证了AZP的结构和结晶度。大环和聚合物的骨架由全sp2杂化的C/N原子组成，具有π共轭和电活性。他们的研究提供了一种合理的方法，通过组合不同的动态共价化学来获得动态稳定的二维晶体聚合物。

据了解，由于合成方法的限制，π共轭晶体二维聚合物的合成仍未得到广泛的探索。

附：英文原文

Title: 1,6-Anthrazoline-linked π-Conjugated Macrocycles and Two-dimensional Polymer via Friedländer Synthesis

Author: Jun Zhu, Shaofei Wu, Xudong Hou, Jishan Wu

Issue&Volume: 2021-09-25

Abstract: Synthesis of π-conjugated crystalline two-dimensional (2D) polymers remains largely unexplored due to limited synthetic methodology. Herein, we report the preparation of a 1,6-anthrazoline (AZ)-linked crystalline 2D polymer  AZP  via acid mediated Friedlnder synthesis. The feasibility was examined first by two model reactions, followed by synthesis of three AZ-based macrocycles  MCn  (n=5-7), in which hexagonal  MC6  was isolated as the major product. The favorable macrocycle formation could be largely attributed to the dynamic feature of Friedlnder synthesis, which involves both imine condensation and aldol condensation. The structure and crystallinity of  AZP  were confirmed by experiments and simulation. The skeletons of the macrocycles and polymer consist of all-sp2  hybridized C/N atoms and are thus π-conjugated and electro-active. Our studies provide a rational way to access kinetically stable 2D crystalline polymers by combination of different dynamic covalent chemistries.

DOI: 10.1002/anie.202112409

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202112409