Ueda Masahiro, Kimura Masaki, Miyagawa Shinobu, Takaya Hikaru, Naito Masaya, Tokunaga Yuji
Department of Materials Science and Engineering Faculty of Engineering, University of Fukui Bunkyo, Fukui, 910-8507, Japan.
International Research Center for Elements Science Institute for Chemical Research, Kyoto University, Uji, 611-0011, Japan.
Chem Asian J. 2020 Jul 16;15(14):2212-2217. doi: 10.1002/asia.202000452. Epub 2020 Jun 22.
In this study we synthesized two- and four-armed porphyrins - bearing two carboxyl and four 2-aminoquinolino functionalities, respectively, at their meso positions - as a complementary hydrogen bonding pair for the self-assembly of a D -symmetric porphyrin trimer host. Two units of the two-armed porphyrin and one unit of the four-armed porphyrin self-assembled quantitatively into the D -symmetric porphyrin trimer, stabilized through ammidinium-carboxylate salt bridge formation, in CH Cl and CHCl . The porphyrin trimer host gradually bound two units of 1,3,5-trinitrobenzene between the pair of porphyrin units, forming a five-layer aromatic structure. At temperatures below -40 °C, the rates of association and dissociation of the complexes were slow on the NMR spectroscopic time scale, allowing the 1 : 1 and 1 : 2 complexes of the trimer host and trinitrobenzene guest(s) to be detected independently when using less than 2 eq of trinitrobenzene. Vis titration experiments revealed the values of K (2.1±0.4×10 M ) and K (2.2±0.06×10 M ) in CHCl at room temperature.
在本研究中，我们合成了两种中卟啉和四臂卟啉，它们在中位分别带有两个羧基和四个2-氨基喹啉官能团，作为用于自组装D对称卟啉三聚体主体的互补氢键对。两臂卟啉的两个单元和四臂卟啉的一个单元在CH₂Cl₂和CHCl₃中通过脒基 - 羧酸盐桥的形成定量自组装成D对称卟啉三聚体并得以稳定。卟啉三聚体主体在一对卟啉单元之间逐渐结合两个1,3,5 - 三硝基苯单元，形成五层芳香结构。在低于 - 40°C的温度下，配合物的缔合和解离速率在核磁共振光谱时间尺度上较慢，当使用少于2当量的三硝基苯时，可以独立检测到三聚体主体与三硝基苯客体的1:1和1:2配合物。可见滴定实验揭示了在室温下CHCl₃中K₁（2.1±0.4×10³ M⁻¹）和K₂（2.2±0.06×10⁴ M⁻²）的值。
