美国佛罗里达大学教授Adam S. Veige团队报道了环聚乙炔的合成。相关研究成果于2021年6月3日发表于国际顶尖学术期刊《Nature Chemistry》。

本文介绍了通过均相钨催化乙炔聚合的环聚乙炔（c-PA）或[∞]环烯的合成。由于其独特的环状结构和拓扑结构，即使在94℃合成，c-PA含有99%以上的反式双键。高活性和低催化剂负载允许合成暂时可溶的c-PA，从而打开了在溶液中衍生聚合物的机会。循环拓扑结构的绝对证据来自于可溶性c-PA生成的衍生物的原子力显微镜图像。

现在可以获得其循环形式，通过初步的表征研究来阐明与传统合成的线性聚乙炔相比的拓扑差异。合成c-PA的一个优点是直接合成反式-反式异构体。c-PA具有低缺陷浓度、低孤子浓度和相对较高的共轭长度等特征。高效催化能够快速合成有光泽的c-PA柔性薄膜，并且当掺杂I2时，它们具有高导电性（398(±76) Ω1cm1）。

附：英文原文

Title: Cyclic polyacetylene

Author: Zhihui Miao, Stella A. Gonsales, Christian Ehm, Frederic Mentink-Vigier, Clifford R. Bowers, Brent S. Sumerlin, Adam S. Veige

Issue&Volume: 2021-06-03

Abstract: Here we demonstrate the synthesis of cyclic polyacetylene (c-PA), or [∞]annulene, via homogeneous tungsten-catalysed polymerization of acetylene. Unique to the cyclic structure and evidence for its topology, the c-PA contains >99% trans double bonds, even when synthesized at 94°C. High activity with low catalyst loadings allows for the synthesis of temporarily soluble c-PA, thus opening the opportunity to derivatize the polymer in solution. Absolute evidence for the cyclic topology comes from atomic force microscopy images of bottlebrush derivatives generated from soluble c-PA. Now available in its cyclic form, initial characterization studies are presented to elucidate the topological differences compared with traditionally synthesized linear polyacetylene. One advantage to the synthesis of c-PA is the direct synthesis of the trans–transoid isomer. Low defect concentrations, low soliton concentration, and relatively high conjugation lengths are characteristics of c-PA. Efficient catalysis permits the rapid synthesis of lustrous flexible thin films of c-PA, and when doped with I2, they are highly conductive (398 (±76) Ω1cm1).

DOI: 10.1038/s41557-021-00713-2

Source: https://www.nature.com/articles/s41557-021-00713-2