X-ray diffraction study on the aggregate structure of 5,10,15,20-tetra(4-sulfophenyl)porphinatopalladium(II)(4-) in aqueous solution
作者:Kazuteru Shinozaki、Kyoko Miwa、Haruhiko Yokoyama、Hideyo Matsuzawa
DOI:10.1039/ft9969201935
日期:——
The aggregate structure of 5,10,15,20-tetra(4-sulfophenyl)porphinatopalladium(II) ion (PdTPPS4–) in aqueous solution has been investigated in terms of the distance between the porphyrin monomers, by use of absorption spectroscopy, paramagnetic relaxation of NMR signals, and an isomorphic substitution method for X-ray diffraction of the solution. From absorption spectroscopy results it was concluded that the aggregate was regarded as a dimer arising from hydrophobic attraction between the porphyrin rings. Paramagnetic effects on the longitudinal relaxation time (T1) for 13C NMR of PdTPPS4– by the addition of 5,10,15,20-tetra(4-sulfophenyl)porphinatocopper(II)(CuTPPS4–) suggested that the paramagnetic centre was located along a C4-axis of PdTPPS4– in a PdTPPS4––CuTPPS4– dimer. The dimer of PdTPPS4– was determined to have a twisted face-to-face stacked structure (D4d) at a distance of 4.1 Å by the isomorphic substituted X-ray diffraction study on PdTPPS4– and CuTPPS4– solutions.
水溶液中5,10,15,20-四(4-磺酸苯基)卟啉合钯(II)离子(PdTPPS4–)的聚集体结构通过吸收光谱学、核磁共振信号的顺磁性弛豫以及溶液的同构取代X射线衍射方法,从卟啉单体之间的距离角度进行了研究。从吸收光谱学结果得出结论,聚集体被视为由卟啉环之间的疏水吸引力产生的二聚体。通过添加5,10,15,20-四(4-磺酸苯基)卟啉合铜(II)离子(CuTPPS4–)对PdTPPS4–的13C NMR纵向弛豫时间(T1)的顺磁性效应表明,顺磁中心位于PdTPPS4––CuTPPS4–二聚体中PdTPPS4–的C4轴上。通过同构取代的X射线衍射研究PdTPPS4–和CuTPPS4–溶液,确定PdTPPS4–的二聚体具有扭曲的面对面堆叠结构(D4d),距离为4.1 Å。