Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States.
J Org Chem. 2021 Sep 3;86(17):12024-12033. doi: 10.1021/acs.joc.1c01385. Epub 2021 Aug 19.
Nucleotide-induced conformational changes in motor proteins are key to many important cell functions. Inspired by this biological behavior, we report a simple chemically fueled system that exhibits carbodiimide-induced geometry changes. Bridging via transient anhydride formation leads to a significant reduction of the twist about the biaryl bond of substituted diphenic acids, giving a simple molecular clamp. The kinetics are well-described by a simple mechanism, allowing structure-property effects to be determined. The kinetic parameters can be used to derive important characteristics of the system such as the efficiencies (anhydride yields), maximum anhydride concentrations, and overall lifetimes. Transient diphenic anhydrides tolerate steric hindrance ortho to the biaryl bond but are significantly affected by electronic effects, with electron-deficient substituents giving lower yields, peak conversions, and lifetimes. The results provide useful guidelines for the design of functional systems incorporating diphenic acid units.
核苷酸诱导的运动蛋白构象变化是许多重要细胞功能的关键。受此生物行为的启发，我们报告了一种简单的化学燃料系统，该系统表现出碳二亚胺诱导的几何形状变化。通过瞬态酸酐形成桥接导致取代二苯并酸的联苯键的扭转显著减小，形成简单的分子夹。动力学很好地用一个简单的机制来描述，允许确定结构-性能的影响。动力学参数可用于得出系统的重要特性，如效率（酸酐产率）、最大酸酐浓度和整体寿命。瞬态二苯并酸酐可以容忍联苯键邻位的空间位阻，但会受到电子效应的显著影响，缺电子取代基会导致产率、峰值转化率和寿命降低。这些结果为设计包含二苯并酸单元的功能系统提供了有用的指导。
