Self-Assembly of Radially π-Extended Tetrathiafulvalene Tetramers for Visible and Near Infrared Electrochromic Nanofiber
作者:Masashi Hasegawa、Masahiko Iyoda
DOI:10.1246/bcsj.20190283
日期:2020.1.15
The self-assembly and electrochromic nanofiber formation of radially π-extended tetrathiafulvalene (TTF) tetramers anchored to 1,2,4,5-tetraethynylbenzene were investigated. The tetramer with SBu-substituents underwent self-assembly in solution. Cationic species of the tetramer, obtained by chemical oxidation with Fe(ClO4)3, exhibited a marked electrochromism in the solution. Their electronic spectra revealed absorption bands corresponding to intermolecular mixed-valence aggregation based on (TTF//TTF)•+, and π-aggregation based on (TTF•+//TTF•+) due to the strong molecular association in the cationic species. Furthermore, the tetramer formed an entangled nanoscale fibrous material from CHCl3–hexane. Electrochemical oxidation of the nanofiber on an indium tin oxide electrode revealed a repeatable redox profile. The nanofiber displayed remarkable electrochromic behavior: the color of the fiber changed from purple (neutral) to brown/brownish green (dication and trication) and green (tetracation). These color changes of the nanofiber are similar to those in solution, and the electronic spectra of the oxidized nanofibers reflected the stacked TTF units in the cationic nanofibers.
hexakis(oligothienylethynyl)benzene with C6 symmetry shows solvatochromic fluorescence with a marked redshift in emission. Furthermore, the star‐shaped molecule shows a fairly large two‐photon absorption property. Interestingly, the molecule forms fluorescent fibrous materials from hexane, DMF, and isopropyl alcohol owing to its disc‐like structure (see graphic).
cyclic voltammetry (CV), which revealed the presumed multielectron redox properties. Compound 4b exhibited a one-step, two-electron reduction wave upon CV, which revealed the formation of the dianion stabilized by two 6-azulenylethynyl substituents under electrochemical reduction conditions. Four 6-azulenylethynyl substituents on a benzene ring in a 1,2,4,5 relationship increased the electron-accepting properties
Synthesis and Properties of Mono-, Bis-, Tris-, and Tetrakis[1,1,4,4-tetracyano-2-(1-azulenyl)-1,3-butadien-3-yl] Chromophores Connected to a Benzene Ring by Phenylethynyl- and 2-Thienylethynyl Spacers
Mono-, bis-, tris-, and tetrakis[(1-azulenylethynyl)phenylethynyl- and (1-azulenylethynyl)-2-thienylethynyl]benzenes have been prepared by Pd-catalyzed alkynylation of iodobenzene derivatives or 2-...
NMR spectroscopies and Mössbauer spectrometry. The experimental data show that 1 behaves as a class II mixed‐valence complex with the positive charges preferentially disposed on antipodal positions. This new molecule can be regarded as a potential molecular prototype of quantumdotcellularautomata.
通过三个序列获得了前所未有的四铁指示[Cp *(dppe)FeC≡C‐} 4-μ(1,2,4,5-C 6 H 2)](PF 6)2(1) 1,2,4,5-四乙炔基苯,Cp *(dppe)FeCl(Cp * = C 5 Me 5,dppe = 1,2-双(二苯基膦基)乙烷),KO t Bu和六氟磷酸铯的反应。以77%的收率分离出的目标分子的循环伏安图,显示出四个分离良好且可逆的氧化还原事件,表明1相对于歧化是热力学稳定的(K c> 10 6)。四核药物用XRD在单晶,IR和NMR光谱以及Mössbauer光谱上表征1。实验数据表明1表现为II类混合价复合物,其中正电荷优先置于对映体位置。这种新分子可以被认为是量子点细胞自动机的潜在分子原型。