Invited for this month's cover are Iwona and Jean‐François Nierengarten from the University of Strasbourg. The cover picture shows the structure of a [2]rotaxane building block bearing 3,5‐bis(trifluoromethyl) benzenesulfonate (BTBS) stoppers. The BTBS moieties of this compound are good leaving groups allowing to perform stopper exchange by treatment with different nucleophiles to afford the corresponding rotaxanes with ester, ether or thioether stoppers. Read the full text of their Full Paper at 10.1002/open.202000035.

中文翻译：

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塞子交换策略面向多样性的支柱[5]芳烃-[2]轮烷的制备

斯特拉斯堡大学的Iwona和Jean-FrançoisNierengarten邀请了本月的封面。封面图片显示了带有3,5-双（三氟甲基）苯磺酸盐（BTBS）塞子的[2]轮烷结构单元的结构。该化合物的BTBS部分是良好的离去基团，允许通过用不同的亲核试剂处理进行塞子交换，以提供具有酯，醚或硫醚塞子的相应的轮烷。阅读其论文全文，网址为10.1002 / open.202000035。