Photoswitchable π-Extended Dithienylethenes with an Attached Molecular Recognition Site
作者:Iris Bittner、Ulrich Lüning
DOI:10.1002/ejoc.201800101
日期:2018.6.7
Photoswitchabledithienylethenes have been extended in positions 5 and 5′ with π‐systems resulting in absorptions of light with longer wavelengths when electrocyclization and ‐reversion are carried out. The extended π‐systems also improve conductivities potentially. cis‐Orientation of the thienyl rings was accomplished by integrating the central double bond into maleic imides. The nitrogen atoms of
可光开关的二噻吩基乙烯在π系统中在5和5'位处扩展,导致在进行电环化和还原时吸收具有更长波长的光。扩展的π系统还可以潜在地提高电导率。噻吩基环的顺式取向是通过将中心双键整合到顺丁烯二酰亚胺中实现的。酰亚胺的氮原子被汉密尔顿受体取代,从而使互补宾客(如巴比妥酸盐)发生超分子结合。实现了光电开关和接收器之间的刚性和柔性连接。所得的光开关在多个循环中显示出可逆转换,并且能够以> 10 4 m –1的结合常数结合巴比妥酸二乙酯。
Determination of Binding Constants of Hydrogen-Bonded Complexes by ITC, NMR CIS, and NMR Diffusion Experiments
amides. The association constants were determined by (1)H NMR titrations monitoring chemically induced shifts (CIS values), by (1)H NMRdiffusionexperiments, and by isothermal titration calorimetry (ITC), giving K(ass) values in chloroform at 298 K between 33 x 10(3) and 100 x 10(3) M(-1).
巴比妥和各种酰基氨基吡啶基间苯二甲酰胺(汉密尔顿受体)之间的主客体复合物形成已被定量确定。描述了九种间苯二甲酰胺的合成。它们的结构在中心间苯二甲酸单元上的取代模式和酰基残基的性质上有所不同。证明乙基己酰基衍生物比戊酰基酰胺更易溶解。缔合常数由 (1) H NMR 滴定监测化学诱导位移 (CIS 值)、(1) H NMR 扩散实验和等温滴定量热法 (ITC) 确定,在 298 K 的氯仿中给出 K(ass) 值介于 33 x 10(3) 和 100 x 10(3) M(-1) 之间。