上海交通大学Xuzhou Yan研究组取得一项新突破。他们的最新研究制备了微观和宏观都坚韧的低聚[2]索烃。2023年4月13日出版的《美国化学会杂志》发表了这项成果。

该研究组合成了一个低聚[2]索烃，展示出微观和宏观尺度都坚韧的机械属性。结构设计的主要特点是控制[2]索烃的金属配位核心的受力点，通过外力下金属配位键的解离和随之而来分子内的旋转、平移和延伸最大化分散能量。因此，在微观层面上，单分子力学光谱测量展示出，需要破碎动态键所需的力创纪录地达到588±233 pN。

在宏观层面上，他们的低聚[2]索烃表现为有报道的最坚韧索烃材料（15.2 vs 2.43 MJ / m³）。这些基本的发现不仅深化了具有全套动态属性的低聚[2]索烃的结构-特质关系的理解，还提供了一个制造高性能机械联锁索烃材料的指导原则。

据介绍，聚索烃是极具吸引力的拓扑架构，因其具备高自由度的构象和机械联锁大环的多种运动模式。然而，利用这些特有的结构和动态特性开发坚韧的索烃材料仍然是一个具有挑战性的目标。

附：英文原文

Title: Oligo[2]catenane That Is Robust at Both the Microscopic and Macroscopic Scales

Author: Ruixue Bai, Zhaoming Zhang, Weishuai Di, Xue Yang, Jun Zhao, Hao Ouyang, Guoquan Liu, Xinhai Zhang, Lin Cheng, Yi Cao, Wei Yu, Xuzhou Yan

Issue&Volume: April 13, 2023

Abstract: Polycatenanes are extremely attractive topological architectures on account of their high degrees of conformational freedom and multiple motion patterns of the mechanically interlocked macrocycles. However, exploitation of these peculiar structural and dynamic characteristics to develop robust catenane materials is still a challenging goal. Herein, we synthesize an oligo[2]catenane that showcases mechanically robust properties at both the microscopic and macroscopic scales. The key feature of the structural design is controlling the force-bearing points on the metal-coordinated core of the [2]catenane moiety that is able to maximize the energy dissipation of the oligo[2]catenane via dissociation of metal-coordination bonds and then activation of sequential intramolecular motions of circumrotation, translation, and elongation under an external force. As such, at the microscopic level, the single-molecule force spectroscopy measurement exhibits that the force to rupture dynamic bonds in the oligo[2]catenane reaches a record high of 588 ± 233 pN. At the macroscopic level, our oligo[2]catenane manifests itself as the toughest catenane material ever reported (15.2 vs 2.43 MJ/m3). These fundamental findings not only deepen the understanding of the structure-property relationship of poly[2]catenanes with a full set of dynamic features but also provide a guiding principle to fabricate high-performance mechanically interlocked catenane materials.

DOI: 10.1021/jacs.3c00221

Source: https://pubs.acs.org/doi/10.1021/jacs.3c00221