765-58-2Relevant academic research and scientific papers
Emission behavior of a symmetrical sexthiophene
Li, Xiaochuan,Zhang, Haiyang,Son, Young-A
, p. 240 - 248 (2017)
Detailed absorption and emission behavior were investigated for a sexthiophene molecule in solution, film, and solid. Only strong polarity solvent could result a notable influence on the quench of its fluorescence. In weak and medium polar environment, including in polymer matrix, highly emissive behavior was maintained and exhibit large Stokes shift. More important is its highly emissive in solid state due to the twisted molecular conformation. However, the bandwidth of solid emission (FWHM: 2149 cm?1) is similar to that of solution emission. The calculated frontier orbital based on TDDFT theory uncovered the underlying signal mechanism furtherly.
Thiophene Modulated BODIPY Dye as a Light Harvester
Li, Xiaochuan,Liao, Meifei,Sun, Jia,Heo, Gisu,Son, Young-A
, p. 127 - 136 (2019/08/20)
A new BODIPY dye with terthiophene branched is configured by Sonogashira coupling and fully characterized by NMR and MS. In general organic solvents, it emits typical green fluorescence ranging in 513-518 nm, like most BODIPY analogues. The terthiophene substitution is greatly improved and the emission peak does not sensitive to the polarity environment. More importantly, the terthiophene plays the role of antenna, harvesting the 340 nm’s excitation energy and transferring the energy to BODIPY efficiently. Even though the molar extinction coefficient in 340 nm is lower than that of maximum absorption, it can enlarge the pseudo Stoke’s shift to ～170 nm, well separating the excitation and emission. In film, the emission shifted to 562 nm due to the polymer chain dissipation part of the energy. It shifted further to 585 nm in solid. The branched terthiophene configures a twisted molecular conformation, which avoids the dye regular packing. Highly emission, excellent solubility and stability constitute the general character of the thiophene attached BIDIPY dye.
Environmentally benign indole-catalyzed position-selective halogenation of thioarenes and other aromatics
Shi, Yao,Ke, Zhihai,Yeung, Ying-Yeung
supporting information, p. 4448 - 4452 (2018/10/17)
Halogenated aromatic compounds are the cores of many pharmaceutical, agricultural and chemical products but they are commonly prepared using electrophilic halogenation reactions in non-green chlorinated solvents under harsh conditions. A separate problem happens in the aromatic halogenation of thioarenes because they readily undergo oxidative side-reactions. Herein we report an environmentally benign electrophilic bromination of aromatics using an indole-catalytic protocol, which is suitable for a wide range of substrates including thioarenes.
Photoswitchable π-Extended Dithienylethenes with an Attached Molecular Recognition Site
Bittner, Iris,Lüning, Ulrich
, p. 2592 - 2602 (2018/05/14)
Photoswitchable dithienylethenes 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 the imides were substituted by a Hamilton receptor allowing supramolecular binding of complementary guests such as barbiturates. Both, a stiff and a flexible connection between photoswitch and receptor was realized. The resulting photoswitches showed reversible switching over several cycles and were able to bind diethyl barbiturate with binding constants of > 104 m–1.
Synthesis of fungicidally active succinate dehydrogenase inhibitors with novel difluoromethylated heterocyclic acid moieties
Walter, Harald,Lamberth, Clemens,Corsi, Camilla
, p. 791 - 799 (2017/12/11)
Abstract: Novel fungicidally active succinate dehydrogenase inhibitors have been prepared, which either carry a difluoromethyl and methyl-bearing pyrazoline, pyrrole, or thiophene ring in the acid component, mimicking similar-substituted pyrazole carboxamides. As five-membered heterocyclic systems with such a special substitution pattern are barely known, unique synthesis routes had to be developed, which rely, e.g., on the van Leusen pyrrole synthesis and the halogen dance reaction. Synthesis and biological activity against selected Ascomycete pathogens of these difluoromethylated pyrazoline, pyrrole, and thiophene derivatives are reported.
SUBSTITUTED 1H-IMIDAZO[4,5-B]PYRIDIN-2(3H)-ONES AND THEIR USE AS GLUN2B RECEPTOR MODULATORS
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Page/Page column 134, (2018/04/23)
Substituted 1 H-imidazo[4,5-b]pyridin-2(3H)-ones as NR2B receptor ligands. Such compounds may be used in NR2B receptor modulation and in pharmaceutical compositions and methods for the treatment of disease states, disorders, and conditions mediated by NR2B receptor activity.
A BODIPY-based highly emissive dye with thiophene-based branch harvesting the light
Li, Xiaochuan,Han, Yujie,Kim, Myeong Jin,Son, Young-A
, p. 157 - 164 (2018/06/11)
A novel BODIPY-based dye with highly emissive character was configured by Sonogashira coupling and routinely characterized by NMR and MS technology. The emission of dye was investigated in solution/film/solid and shows intensive emission. In solution, the emission peak appeared around 510?nm with little influence by the polar environment. The terthiophene plays an effective antenna effect, harvesting the light and transferring the energy to BODIPY. The pseudo Stoke's shift enlarged to ～170?nm in solution. In film, the emission peak shifted to 563?nm in polycarbonate matrix. And it shifted further to 585?nm in solid due to the highly twisted structure, which avoided closely regular-tight packing. The dye rendered an intense fluorescence, good optothermal stability, and high fluorescence quantum yield (0.55). The solid emission showed highly red emission with Commission Internationale de L'Eclairage (CIE) coordinates of (X = 0.69, Y = 0.31). Thus, the synthesized dye is idea candidate for emitting materials.
Design, syntheses and photochromic properties of dithienylcyclopentene optical molecular switches
Yu, Chuanming,Hu, Bingcheng,Liu, Cheng,Li, Jiting
, (2016/12/22)
A kind of basal diarylethene through an easy synthetic procedure was synthesized and characterized, and a Suzuki coupling reaction was frequently operated to obtain the diarylethenes derivatives with some vivid functional groups like bromo, amido and pyridine. Two methods for derivatives of these switches contain porphyrins were described. All of their spectroscopic and photochromic properties were studied and intercompared. It is indicated that the difference in electron densities of the π-conjugated system of the closed forms has effects upon the absorption maxima in visible region of UV–Vis spectra. Dithienylcyclopentenes linked to porphyrins could emit luminescence substantially that display potentials to be used in the applications of nondestructive readout upon binary data storage and smart materials.
Functionalization of photochromic dithienylmaleimides
Wutz,Falenczyk,Kuzmanovic,K?nig
, p. 18075 - 18086 (2015/03/04)
Photochromic dithienylmaleimides are well known molecular switches, but for applications the suitable functionalization of the photochromic scaffold is required. We report here synthetic routes to dithienylmaleimides, which are functionalized at three different positions: at each of the thiophene moieties and the maleimide nitrogen. A Perkin-type condensation of two thiophene precursors is used as the key step to assemble the maleimide core, which allows the synthesis of non-symmetrically substituted dithienylmaleimides, such as photochromic amino acids. A different approach to the maleimide core is provided by the reaction of a dithienylmaleic anhydride with amines or hydrazides leading to maleimide protected dithienylmaleimides and photochromic labeled natural amino acids. The photochromic properties of the new photoswitches were investigated showing reversible photochromism in polar organic solvents. This journal is
π-complexation in nickel-catalyzed cross-coupling reactions
Sontag, S. Kyle,Bilbrey, Jenna A.,Huddleston, N. Eric,Sheppard, Gareth R.,Allen, Wesley D.,Locklin, Jason
, p. 1836 - 1841 (2014/03/21)
The kinetic isotope effect (KIE) is used to experimentally elucidate the first irreversible step in oxidative addition reactions of a zerovalent nickel catalyst to a set of haloarene substrates. Halogenated o-methylbenzene, dimethoxybenzene, and thiophene derivatives undergo intramolecular oxidative addition through irreversible π-complexation. Density functional theory computations at the B3LYP-D3/TZ2P-LANL2TZ(f)-LANL08d level predict η2-bound π-complexes are generally stable relative to a solvated catalyst plus free substrate and that ring-walking of the Ni(0) catalyst and intramolecular oxidative addition are facile in these intermediates.
