Department of Chemistry, Marquette University, Milwaukee, Wisconsin, 53201-1881, USA.
Chemistry. 2018 Nov 27;24(66):17439-17443. doi: 10.1002/chem.201804245. Epub 2018 Oct 30.
Calixarenes have found widespread application as building blocks for the design and synthesis of functional materials in host-guest chemistry. The ongoing desire to develop a detailed understanding of the nature of NO bonding to multichromophoric π-stacked assemblies led us to develop an electron-rich methoxy derivative of calix[4]arene (3), which we show exists as a single conformer in solution at ambient temperature. Here, we examine the redox properties of this derivative, generate its cation radical (3 ) using robust chemical oxidants, and determine the relative efficacy of its NO binding in comparison with model calixarenes. We find that 3/3 is a remarkable receptor for NO /NO, with unprecedented binding efficacy. The availability of precise experimental structures of this calixarene derivative and its NO complex, obtained by X-ray crystallography, is critically important both for developing novel functional NO biosensors, and understanding the role of stacked aromatic donors in efficient NO binding, which may have relevance to biological NO transport.
冠醚在主客体化学中作为设计和合成功能材料的构建块得到了广泛的应用。为了深入了解 NO 与多生色π-堆叠组装体的结合性质，我们开发了一种电子富有的甲氧基取代杯[4]芳烃（3），我们证明它在环境温度下以单一构象存在于溶液中。在这里，我们研究了该衍生物的氧化还原性质，使用强大的化学氧化剂生成其阳离子自由基（3+），并确定其与模型杯芳烃相比的 NO 结合的相对效力。我们发现 3/3+是一种用于 NO/NO 的显著受体，具有前所未有的结合效力。通过 X 射线晶体学获得的这种杯芳烃衍生物及其 NO 配合物的精确实验结构的可用性对于开发新型功能 NO 生物传感器以及理解堆叠芳香供体在有效 NO 结合中的作用至关重要，这可能与生物 NO 运输有关。
