154566-69-5Relevant articles and documents
Reversible photochromism of novel silver(I) coordination complexes with 1,2-bis(2′-methyl-5′-(2″-pyridyl)-3′-thienyl)perfluorocyclopentene in crystalline phase
Munakata, Megumu,Han, Jing,Nabei, Atsuhiro,Kuroda-Sowa, Takayoshi,Maekawa, Masahiko,Suenaga, Yusaku,Gunjima, Nozomu
, p. 4281 - 4288 (2006)
Three novel silver(I) complexes with 1,2-bis(2-methyl-5′-(2″-pyridyl)-3′-thienyl)perfluorocyclopentene (BM-2-PTP) were synthesized by the reaction of Ag(CF3SO3) or Ag(CF3COO) with BM-2-PTP in benzene at different temperatures. The structures of these metal complexes were revealed by X-ray crystallographic analyses and the correlation between crystal structures and photochromic performance was discussed. In complexes 1 and 2, silver(I) is three-coordinated to two nitrogens from distinct ligand molecules as well as one oxygen from anions to form a 1-D polymeric structure. On the other hand, complex 3 contains two crystallographic independent Ag(I) with different coordination environments, and the adjacent BM-2-PTP molecules are connected by Ag-CF3CO2-Ag chains to afford a 1-D double chain structure. The difference in structures of three complexes shows the interesting anionic effect on coordination and the subtleness of crystal engineering. It is noted that complex 3 underwent reversible photochromic reaction in crystalline state despite the unfavorable framework to the rotation of thiophene groups.
Packing Structure Effects on the Slow Magnetic Relaxation Pathways of Dysprosium (III) Complexes
Kamila, Mritunjoy,Cosquer, Goulven,Breedlove, Brian K.,Yamashita, Masahiro
, p. 595 - 603 (2017)
Three complexes, [Dy{5-(5-methylthiophen-2-yl)-2,2- bipyridine}(hfac)3] (6), [Dy{5-(4-bromo-5-methylthiophen-2- yl)-2,2-bipyridine}(hfac)3] (7) and [Dy{5-(4-ethynyl-5-methylthio- phen-2-yl)-2,2-bipyridine}(hfac)3] (8) (hfac = hexafluoroacetylacetate), were synthesized to investigate the effects of substituents on the ligand far from the metal ion on the magnetic properties of the dysprosium ion. 7 crystallized in two polymorphs (P21/n for 7a and P21/a for 7b), whereas 6 and 8 crystallized in one polymorph (P21/n and P21/a, respectively). All of the complexes have columnar structures, and in 6 and 7a, there are stacking interactions between neighboring aromatic rings in contrast to compounds 7b and 8, which do not show such interactions. Every complex underwent slow magnetic relaxation with a single relaxation time, except for complex 7a, for which there were two relaxation times. In order to clarify the role of distal substitution and crystal packing, the magnetic properties were studied in solution, where all of the complexes show single relaxation times.
Development of Red-Shifted and Fluorogenic Nucleoside and Oligonucleotide Diarylethene Photoswitches
Kolmar, Theresa,Becker, Antonia,Pfretzschner, Ronja A.,Lelke, Alina,J?schke, Andres
supporting information, p. 17386 - 17394 (2021/10/20)
The reversible modulation of fluorescence signals by light is of high interest for applications in super-resolution microscopy, especially on the DNA level. In this article we describe the systematic variation of the core structure in nucleoside-based diarylethenes (DAEs), in order to generate intrinsically fluorescent photochromes. The introduction of aromatic bridging units resulted in a bathochromic shift of the visible absorption maximum of the closed-ring form, but caused reduced thermal stability and switching efficiency. The replacement of the thiophene aryl unit by thiazol improved the thermal stability, whereas the introduction of a benzothiophene unit led to inherent and modulatable turn-off fluorescence. This feature was further optimized by introducing a fluorescent indole nucleobase into the DAE core, resulting in an effective photoswitch with a fluorescence quantum yield of 0.0166 and a fluorescence turn-off factor of 3.2. The site-specific incorporation into an oligonucleotide resulted in fluorescence-switchable DNA with high cyclization quantum yields and switching efficiency, which may facilitate future applications.
Switchable Mesomeric Betaines Derived from Pyridinium-Phenolates and Bis(thienyl)ethane
Adams, J?rg,Dahle, Sebastian,Hübner, Eike G.,Lederle, Felix,Maus-Friedrichs, Wolfgang,Nagorny, Sven,Schmidt, Andreas,Udachin, Viktor,Weingartz, Thea
, p. 3178 - 3189 (2021/07/02)
Syntheses of push–pull substituted non-symmetric bis(thienyl)ethenes (BTEs) possessing a central perfluorocyclopentene core are described. The substituent effects of anisole, phenole, and phenolate as well as pyridine, pyridinium, and N-methylpyridinium substituents, joined through their 3- or 4-positions to the central BTE core, respectively, cover the range from very strongly electron-donating [σ(4-phenolate)=?1.00] to extremely strongly electron-withdrawing [σ(pyridinium-4-yl)=+2.57] in the title mesomeric betaines. The different isomers possessing 4-yl/4-yl, 4-yl/3-yl and 3-yl/3-yl substituents represent different combinations of conjugated and cross-conjugated partial structures and cause different spectroscopic properties. In addition, through-space conjugation between the 2- and 2′-position of the thiophenes can be observed which circumvents the charge-separation of through-bond cross-conjugation. The BTE possessing the push–pull chromophore consisting of 3-anisole and 4-pyridinium substituents (24) displays the best extinction coefficients within the series of compounds described here (?=33.8/15.7 L/mol ? cm), while the mesomeric betaine possessing an N-methylpyridinium-4-yl and a 4-phenolate substituent (29) displays considerable bathochromic shifts to λmax=724 nm in its closed form.
Photochromic dithienylethenes characterized by: In situ irradiation NMR-spectroscopy and electrochemically induced responsiveness on gold substrates
Von Irmer, Jonas,Frie?, Florian,Herold, Dominik,Kind, Jonas,Thiele, Christina M.,Gallei, Markus
supporting information, p. 14088 - 14097 (2019/12/02)
Photochromic compounds comprising small molecules and polymers have been shown to be of great interest in the field of stimuli-responsive materials for applications as sensors and (nano-) devices. In this regard dithienylethenes (DTEs) have been proven to be especially valuable because of their tolerance to chemicals and their good stability making them tunable and reversibly switchable between an open and a closed structure featuring different optical properties. By utilizing a potent in situ irradiation NMR spectroscopy approach, it is possible to determine the photochromic switching capability of two DTE derivatives in solution leading to crucial information about the structures, the equilibria of the chemical ring-opening and closing of the DTEs as well as the longtime stability of these molecular switches. In particular the perfluorinated thioether bearing compound shows remarkable stability with little fatigue related to the irreversibly cyclized byproduct known for DTEs. The thioether-bearing DTEs can be deprotected and used for immobilization on gold substrates which are characterized by water contact angle measurements prior to and after DTE functionalization. Finally, the electrochemically induced switching capability of the perhydro DTE is investigated by cyclic voltammetry proving its fast, quantitative and reversible cyclization. We envisage these materials for applications as sensors and optical switching devices.