3141-27-3Relevant articles and documents
Synthesis of extended α,α'-oligo(silylthiophenes) by cerium(IV) oxidative coupling reactions
Mustafa, Ali H.,Shepherd, Michael K.
, p. 2743 - 2744 (1998)
Cerium(IV) oxidative dimerisations of 4,4'-bis(trimethylsilyl)-2,2':5',2''-terthiophene and the quaterthienyl analogue 1c gave the corresponding sexi- and octi-thiophenes; the latter have been used to prepare α-linked hexadecithiophene and tetracosithiophene derivatives.
Synthesis of bithiophenesilane dendrimer of the first generation
Ponomarenko,Muzafarov,Borshchev,Vodopyanov,Demchenko,Myakushev
, p. 684 - 690 (2005)
The synthesis of tris{5′-[methylbis(2-thienyl)silyl]2,2′- bithienyl-5-yl} methylsilane, a first-generation bithiophenesilane dendrimer, is described. The conditions of effective formation of methyltrithienylsilane were found; methyltris(5-bromo-2-thienyl)silane and a number of other monofunctional derivatives of methyltrithienylsilane were synthesized for the first time. The advantages and drawbacks of the Suzuki and Kumada reactions for the formation of bithienyl fragments in the synthesis of oligothienylsilane dendrimers are discussed.
The influence of an ethynyl spacer on the electronic properties in 2,5-ferrocenyl-substituted heterocycles Dedicated to Prof. Dr. Claude Lapinte for his outstanding contribution to organometallic chemistry especially to electron transfer studies.
Pfaff, Ulrike,Hildebrandt, Alexander,Korb, Marcus,Lang, Heinrich
, p. 2 - 9 (2015)
A series of binuclear complexes based on five-membered heterocycles featuring alkynyl ferrocenyl groups, 2,5-(FcCC)2-cC4H2E (E = NPh, 3a; S, 3b; O, 3c), has been synthesized using the Sonogashira C,C cross-coupling protocol. The molecular structures of 3a and 3c in the solid state are discussed. The influence of the ethynyl unit on the electronic and (spectro)electrochemical properties of these compounds is shown by cyclic voltammetry (CV), square wave voltammetry (SWV) and in situ UV-Vis-NIR and IR spectroscopy. The high ΔEp values (140-204 mV) of the single reversible redox events indicate that two individual oxidation processes take place in a close potential range. Nevertheless, the NIR measurements indicate weak and broad intervalence charge transfer (IVCT) absorptions for the mixed-valent monocationic species 3a-c+. Compared to 2,5-Fc2-cC4H2E (E = NPh, S, O) the absorptions for the IVCT transitions are shifted hypsochromically, showing that the charge transfer process is promoted at higher excitation energies, due to larger metal-metal distances in 3a-c. The occurrence of IVCT absorptions demonstrates that the 2,5-diethynylferrocenyl heterocycles are class II systems according to Robin and Day.
Donor-Acceptor-Donor Thienopyrazine-Based Dyes as NIR-Emitting AIEgens
Calamante, Massimo,Coppola, Carmen,Dessì, Alessio,Franchi, Daniele,Goti, Giulio,Mordini, Alessandro,Reginato, Gianna,Sinicropi, Adalgisa,Zani, Lorenzo
, p. 2655 - 2664 (2021/06/26)
Organic Near-Infrared luminophores have found broad application as functional materials, but the development of efficient NIR emitters is still a challenging goal. Here we report on a new class of thieno[3,4-b]pyrazine-based NIR emitting materials with Aggregation Induced Emission (AIE) properties. The dyes feature a donor–acceptor–donor (D?A?D) structure, with a thienopyrazine acceptor core connected to two triarylamine donor groups bearing a tetraphenylethylene (TPE) moiety. Fast and efficient synthesis allowed the modular preparation of three dyes of tunable absorption and emission profiles. These constructs were extensively characterized by spectroscopic studies in different solvents, which revealed intense light-harvesting ability and emissions in the deep-red and NIR region with large Stokes shift values. Remarkably, the dyes exhibited AIE properties, retaining emissive ability in the aggregate state, thus emerging as attractive materials for their potential application in the development of luminescent devices.
Electrochromic properties of pyrene conductive polymers modified by chemical polymerization
Chang, Lijing,Hou, Yanjun,Li, Rui,Ma, Yang,Miao, Shoulei,Wang, Cheng,Xu, Haoran,Zhang, Yuhang
, p. 39291 - 39305 (2021/12/27)
Pyrene is composed of four benzene rings and has a unique planar melting ring structure. Pyrene is the smallest condensed polycyclic aromatic hydrocarbon, and its unique structural properties have been extensively studied. Pyrene has excellent properties such as thermal stability, high fluorescence quantum efficiency and high carrier mobility. This paper mainly used thiophene, EDOT and triphenylamine groups to enhance the pyrene based π-conjugated system and control the molecular accumulation of organic semiconductors, and improve their charge transport performances. Five kinds of polymer were synthesized and correspondingly characterized. The five kinds of pyrene conductive polymer had outstanding properties in terms of solubility, fluorescence intensity and thermal stability, good film-forming properties, stable electrochromic properties and high coloring efficiency. The coloration efficiency (CE) of PPYTP was as high as 277 cm2C?1, and the switching response time was short. The coloring time of PPYEDOT was 1.3 s and the bleaching time was 3.2 s. The lower impedance will also provide the possibility of such polymers being incorporated into electrochromic devices in the future. In short, the synthesized new pyrene conductive polymers will have wide application prospects in the field of electrochromic materials.
Role of Substituents at 3-position of Thienylethynyl Spacer on Electronic Properties in Diruthenium(II) Organometallic Wire-like Complexes
Roy, Sourav Saha,Chowdhury, Sabyasachi Roy,Mishra, Sabyashachi,Patra, Sanjib K.
supporting information, p. 3304 - 3313 (2020/09/09)
A series of organometallic complexes [Cl(dppe)2Ru?C≡C-(3-R?C4H2S)-C≡C?Ru(dppe)2Cl] (3-R-C4H2S=3-substituted thienyl moiety; R=?H, ?C2H5, ?C3H7, ?C4H9, ?C6H13, ?OMe, ?CN in 5 a–5 g respectively) have been synthesized by systematic variation of 3-substituents at the thienylethynyl bridging unit. The diruthenum(II) wire-like complexes (5 a–5 g) have been achieved by the reaction of thienylethynyl bridging units, HC≡C-(3-R-C4H2S)-C≡CH (4 a–4 g) with cis-[Ru(dppe)2Cl2]. The wire-like diruthenium(II) complexes undergo two consecutive electrochemical oxidation processes in the potential range of 0.0 - 0.8 V. Interestingly, the wave separation between the two redox waves is greatly influenced by the substituents at the 3-position of the thienylethynyl. Thus, the substitution on 3-position of the thienylethynyl bridging unit plays a pivotal role for tuning the electronic properties. To understand the electronic behavior, density functional theory (DFT) calculations of the selected diruthenium wire-like complexes (5 a–5 e) with different alkyl appendages are performed. The theoretical data demonstrate that incorporation of alkyl groups to the thienylethynyl entity leaves unsymmetrical spin densities, thus affecting the electronic properties. The voltammetric features of the other two Ru(II) alkynyl complexes 5 f and 5 g (with ?OMe and ?CN group respectively) show an apparent dependence on the electronic properties. The electronic properties in the redox conjugate, (5 a+) with Kc of 3.9×106 are further examined by UV-Vis-NIR and FTIR studies, showing optical responses in NIR region along with changes in “?Ru?C≡C?“ vibrational stretching frequency. The origin of the observed electronic transition has been assigned based on time-dependent DFT (TDDFT) calculations.
Synthesis and characterization of poly(tetramethylsilarylenesiloxane) derivatives with oligothiophene based moiety
Nishizawa, Ibuki,Ajito, Hiroki,Gonmori, Yuzuki,Katoh, Ryuzi,Ichikawa, Tsukasa,Nemoto, Nobukatsu
, p. 93 - 101 (2019/02/15)
Poly(tetramethylsilarylenesiloxane) derivatives (P1T-P4T, P4TC) that contained thiophene (1T), oligothiophenes such as dithiophene (2T), terthiophene (3T), quaterthiophene (4T), or 2,6-di(2-thienyl)-4,4-diphenylcyclopentadithiophene (4TC) as the main chain components were synthesized via polycondensation reaction of the corresponding disilanol monomers (M1T-M4T, M4TC). The obtained polymers other than P4T that contained quaterthiophene units exhibited the good solubility in common organic solvents, such as toluene, chloroform, tetrahydrofuran and so on. The glass transition temperature (Tg) and melting temperature (Tm) of the obtained polymers regarding P1T-P4T were increased with the extension of the thiophene rings of the monomeric unit as deduced from the results of the differential scanning calorimetry (DSC). On the other hand, the Tm was not observed for P4TC that was composed of 2,6-di(2-thienyl)-4,4-diphenylcyclopentadithiophene units. P2T that was composed of dithiophene units exhibited the highest temperature at 5% weight loss (Td5) of 467 °C in all present polymers. The bathochromic and hyperchromic effects in the absorption spectra as well as the improvement of fluorescence quantum yield were observed by the introduction of dimethylsilyl group onto the present oligothiophene derivatives. These effects became unremarkable accompanying the elongation of the thiophene rings of the monomeric units; however, 4TC exhibited a more significant change by the introduction of the dimethylsilyl group than the other oligothiophenes derivatives, indicating that the introduction of the cardo-structure was effective in the improvement of the optical properties. M4TC and P4TC exhibited the fluorescence wavelength around 500 nm and the highest fluorescence quantum yield of the present series of poly(tetramethylsilarylenesiloxane) derivatives, i.e., 0.40, plausibly because the free rotation between thiophene rings in oligothiophene inhibited by the cardo-structures and the bulky diphenyl groups at 4-position of cyclopentadithiophene moiety suppressed the nonradiative transition.
Regioselective Halogenation of Arenes and Heterocycles in Hexafluoroisopropanol
Tang, Ren-Jin,Milcent, Thierry,Crousse, Benoit
, p. 930 - 938 (2018/01/28)
Regioselective halogenation of arenes and heterocycles with N-halosuccinimides in fluorinated alcohols is disclosed. Under mild condition reactions, a wide diversity of halogenated arenes are obtained in good yields with high regioselectivity. Additionally, the versatility of the method is demonstrated by the development of one-pot sequential halogenation and halogenation-Suzuki cross-coupling reactions.
Green halogenation reactions for (hetero)aromatic ring systems in alcohol, water, or no solvent
Kajorinne, Jessie K.,Steers, Jennifer C.M.,Merchant, Marnie E.,MacKinnon, Craig D.
, p. 1087 - 1091 (2018/11/25)
A new method of brominating aromatic and heteroaromatic ring systems is investigated. The combination of hydrobromic acid as the halogen source, hydrogen peroxide as the oxidant, and ethanol, water, or no solvent are evaluated as greener conditions than those that have been previously published. The new conditions give high yields and good regioselectivity for a variety of substrates when the ring is activated by electron-donating groups or heteroatoms. Phenols, anisole, thiophenes, and pyrrole give comparable or superior results when compared to a traditional bromination by N-bromosuccinimide in tetrahydrofuran. Other nitrogen-containing heterocycles do not react under the conditions because they are protonated and hence deactivated; similarly, substrates with electron-withdrawing groups are not brominated. The reaction is very tolerant of a variety of functional groups.
TRIPHENYLAMINE COMPOUNDS, POLYMERS MADE THEREFROM AND ELECTROCHROMIC DEVICE COMPRISING THE SAME
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Paragraph 0173; 0176-0179, (2018/05/03)
The present invention relates to a triphenylamine compound, to a polymer thereof and to an electrochromic device comprising the same, and specifically, to a triphenylamine compound represented by the chemical formula (1), to a polymer thereof and to an electrochromic device comprising the same. In the chemical formula (1), R, R1, R2, R3, R4, and R5 are as defined in claim 1. The present invention also provides a triphenylamine-based polymer capable of forming a thin film having uniform surface and exhibiting excellent reversibility in the electrochromic characteristics.COPYRIGHT KIPO 2018
