Monitoring the thermodynamically-controlled formation of diimide-based resin-attached rotaxanes by gel-phase HR MAS<sup>1</sup>H NMR spectroscopy
作者:Kathleen M. Mullen、Ken D. Johnstone、Matthew Webb、Nick Bampos、Jeremy K. M. Sanders、Maxwell J. Gunter
DOI:10.1039/b716325h
日期:——
The thermodynamically controlled self-assembly of rotaxane and pseudorotaxane systems consisting of (i) a naphthodiimide thread unit terminated at one end with a pyridine ligand, and covalently linked at the other to a gel-phase polystyrene resin support, (ii) a dinaphtho-crownether shuttle unit, and (iii) a ruthenium carbonyl metalloporphyrin stopper unit, is investigated by high resolution magic angle spinning proton (HR MAS 1H) NMR spectroscopy. The effects of variable concentration of the solution-phase components, the temperature, and added Li+ and Na+ ions are described, and the limitations of the technique are addressed. The dynamic behaviour is compared directly to the solution-phase analogues, where a bulky stopper group is substituted for the polystyrene resin bead.
热力学控制的轮烷和伪轮烷系统的自组装包括:(i) 一端以吡啶配体为末端的萘二亚胺线单元,另一端与凝胶相聚苯乙烯树脂支撑物共价连接、(iii) 一个钌羰基金属卟啉塞单元,通过高分辨率魔角旋转质子(HR MAS 1H)核磁共振光谱进行了研究。描述了溶液相成分浓度变化、温度以及添加的 Li+ 和 Na+ 离子的影响,并探讨了该技术的局限性。将其动态行为直接与溶液相类似物进行了比较,在溶液相类似物中,用一个大的塞子基团代替了聚苯乙烯树脂珠。