104934-51-2Relevant academic research and scientific papers
Construction of giant porphyrin macrorings self-assembled from thiophenylene-linked bisporphyrins for light-harvesting antennae
Fujisawa, Kaori,Satake, Akiharu,Hirota, Shun,Kobuke, Yoshiaki
, p. 10735 - 10744 (2008)
As a model of bacterial photosynthetic light-harvesting antenna, a large number of porphyrin units were organized into barrel-shaped macrorings. Two imidazolylporphyrinatozinc(II) molecules were linked through either unsubstituted thiophenes or 3,4-dioctylthiophenes la and lb, respectively. These structures were spontaneously organized by complementary coordination of the imidazolyl to zinc and produced a series of self-assembled fluorescent polygonal macrorings under high dilution conditions. The ring size increased compared with previous m-phenylene examples. The size distribution was also controlled by the presence of octyl substituents. A wide distribution of macrorings from 7- to > 15-mer was obtained from la, whereas macrorings ranging from 7- to 11-mer with a maximum population focused at the 8-mer were formed with lb. The size distribution was governed by competition between entropy-favored, smaller-ring formation and the enthalpy-favored, less-strained larger macroring. The UV/Vis spectra showed a gradual redshift for the larger rings reflecting an increase in the transition dipole interactions.
Linear and nonlinear optical properties of a quadrupolar carbo-benzene and its benzenic parent: The carbo-merization effect
Barba-Barba, Rodrigo M.,Chammam, Marwa,Ramos-Ortiz, Gabriel,Listunov, Dymytrii,Velusamy, Jayaramakrishnan,Rodriguez, Mario,Carriles, Ramon,Silva, Carlos,Duhayon, Carine,Kauffmann, Brice,Maraval, Valérie,Chauvin, Remi
, (2021)
Herein, the optical properties of thiophene-functionalized quadrupolar carbo-benzenes and a benzenic parent, of generic structure Th–C[tbnd]C–[core]–C[tbnd]C–Th, Th = R2C4HS, are comparatively investigated. Beyond the previously unknown dioctylthienylethynylbenzene (core = p-C6H4, R = nOct), two bis-dialkylthienylethynyl-carbo-benzenes (core = C18Ph4, R = nOct, nBu) are envisaged for the unique “carbo-aromatic” character of the C18 macrocycle. The three targets were synthesized from the corresponding ethynylthiophenes in 47, 20 and 10% yield, respectively, then characterized by classical methods such as NMR spectroscopy, and X-ray crystallography for one of the carbo-benzenes. Regarding linear and nonlinear optical properties, our results show that the carbo-merization induces a significant shift to lower energies of the one-photon electronic excitations accompanied by an 8-fold increase of the molar extinction coefficient compared to the parent molecule. Intriguingly, these excitations lead to a broad band of photoluminescence comprising decay transitions of the type S1 → S0 but also of the type S2 → S0. This phenomenon of emission from higher excited states, which is contrary to Kasha's rule, is assigned to - or revealed by - a reduction of the internal conversion efficiency between S2 and S1. Two-photon induced transitions are also enhanced, the two-photon absorption cross-section (σ2PA) being in average five times larger for the carbo-benzenes than for their benzene parent in the wavelength range 650–950 nm, with a maximum of σ2PA = 1430 GM (1 GM = 10?50 cm4 s/photon). Beyond a moderate nonlinearity, this comparative study provides quantitative insights about the way carbo-merization or insertion of a π-conjugated macrocycle between chromophoric functions (here thiophene rings) can tune optical properties of organic molecules. The optical properties of the bis-dialkylthienylethynyl-carbo-benzenes are also discussed in regard of recent reports on organic chromophores based on other types of π-conjugated macrocyclic cores.
Dithiophene based X-shaped bolaamphiphiles: Liquid crystals with single wall honeycombs and geometric frustration
Gao, Hongfei,Ye, Yafei,Kong, Leiyang,Cheng, Xiaohong,Prehm, Marko,Ebert, Helgard,Tschierske, Carsten
, p. 10921 - 10931,11 (2012)
A series of 5,5′-diphenyl-2,2′-dithiophene based X-shaped polyphiles with two long lateral alkyl chains and terminal glycerol groups was synthesized and the liquid crystalline phases formed by these compounds were investigated by polarizing microscopy, DSC and XRD. These compounds form square (p4mm and p4gm) and hexagonal (p6mm) columnar LC phases. In these mesophases the molecules organize into polygonal honeycombs where the π-conjugated cores form the walls, fused at the edges by the hydrogen bonding networks between the glycerol units and filled by the lateral alkyl chains. By elongation of these chains, a series of polygonal honeycomb phases with a "single wall" structure, ranging from triangular via square and pentagonal to hexagonal was observed. Most triangular honeycombs appear to be defective and can be considered as mixtures of triangular cylinders with orientationally randomized rhombic cylinders. The transition from this improper triangular honeycomb to the square honeycomb takes place via a disordered isotropic phase. Addition of water to this isotropic phase gives rise to a true triangular honeycomb LC phase. Replacing one of the long lateral chains by a small methyl group leads to honeycombs formed by double walls instead of single walls. UV investigations indicate π-stacking of the aromatic cores organized in the honeycomb walls, which is of interest for the potential application of these materials in self assembled arrays of organic electronic material. This journal is
Suzuki-Miyaura coupling catalyzed by a Ni(II) PNP pincer complex: Scope and mechanistic insights
Madera, Justin,Slattery, Megan,Arman, Hadi D.,Tonzetich, Zachary J.
, (2020)
The nickel(II) pincer complex, [NiCl(PhPNP)] (PhPNP = anion of 2,5-bis(diphenylphosphinomethyl)pyrrole), has been employed as a precatalyst for the Suzuki-Miyaura cross-coupling reaction of aryl halides and boronic acids. Both electron-rich and electron-deficient aromatic bromides were found to undergo coupling with boronic acids in modest yield at elevated temperature in the presence of K3PO4·H2O. Preliminary mechanistic studies of the reaction identified a novel species formulated as the boronate complex, [Ni(OB{OH}{2-tolyl})(PhPNP)], which most likely represents a catalyst deactivation pathway. The productive catalytic cycle was found to be most consistent with a Ni(I)/Ni(III) process where the boronic acid serves as both reductant and nucleophile in the presence of base.
The Discovery of Citral-Like Thiophenes in Fried Chicken
Cannon, Robert J.,Curto, Nicole L.,Esposito, Cynthia M.,Payne, Richard K.,Janczuk, Adam J.,Agyemang, David O.,Cai, Tingwei,Tang, Xiao-Qing,Chen, Michael Z.
, p. 5690 - 5699 (2017)
The isomers of 3,7-dimethyl-2,6-octadienal, more commonly known together as citral, are two of the most notable natural compounds in the flavor and fragrance industry. However, both isomers are inherently unstable, limiting their potential use in various applications. To identify molecules in nature that can impart the fresh lemon character of citral while demonstrating stability under acidic and thermal conditions has been a major challenge and goal for the flavor and fragrance industry. In the study of fried chicken, several alkyl thiophenecarbaldehydes were identified by gas chromatography-mass spectrometry and gas chromatography-olfactometry that provided a similar citral-like aroma. The potential mechanism of formation in fried chicken is discussed. Furthermore, in order to explore the organoleptic properties of this structural backbone, a total of 35 thiophenecarbaldehyde derivatives were synthesized or purchased for evaluation by odor and taste. Certain organoleptic trends were observed as the length of the alkyl or alkenyl chain increased or when the chain was moved to different positions on the thiophene backbone. The 3-substituted alkyl thiophenecarbaldehydes, specifically 3-butyl-2-thiophenecarbaldehyde and 3-(3-methylbut-2-en-1-yl)-2-thiophenecarbaldehyde, exhibited strong citrus and citral-like notes. Several alkyl thiophenecarbaldehydes were tested in high acid stability trials (4 °C vs 38 °C) and outperformed citral both in terms of maintaining freshness over time and minimizing off-notes. Additional measurements were completed to calculate the odor thresholds for a select group of thiophenecarbaldehydes, which were found to be between 4.7-215.0 ng/L in air.
Preparation and characterization of ester functionalized poly(3-alkylthiophene)s
Lee,Kim,Rhee
, p. 31 - 38 (1994)
Soluble ester group substituted polythiophenes and copolymers of substituted polythiophenes with 3-octylthiophene were prepared. The decreased conductivities and blue shifts were observed for the substituted polythiophenes. These results indicate the shortening of conjugating length due to the steric repulsion of the ester substituent.
Design, Synthesis, and Control of Conducting Polymer Architectures: Structurally Homogeneous Poly(3-alkylthiophenes)
McCullough, Richard D.,Lowe, Renae D.,Jayaraman, Manikandan,Anderson, Deborah L.
, p. 904 - 912 (1993)
The full details of a facile synthesis of structurally homogeneous poly(3-alkylthiophenes) (PAT's) is presented.In three steps from 3-bromothiophene, PAT's can be made with complete regiochemical control.We define structurally homogenous as a regiochemically well-defined polymer structure that in our case contains almost exclusively head-to-tail couplings (HT-HT) (2,5-couplings between adjacent thiophene rings).By analysis of the NMR data, our poly(n-butylthiophene) (5a) contains 93percent HT-HT couplings, 98percent of the desired regiochemistry is found in poly(n-hexylthiophene) (5b), 97percent in poly(n-octylthiophene), (5c), and 95percent in poly(n-dodecylthiophene), (5d).Quenching studies on reactive intermediates and 13C NMR data also demonstrate the regiochemical purity of these materials.These PAT's show lower energy absorption maximum shifts of up to 14 nm in solution, 46 nm in the solid state, and other intense lower energy peaks with shifts of up to 129 nm (609 nm) from PAT's prepared by the usual methods.All of these data are indicative of longer mean conjugation lengths.Molecular mechanics and ab initio calculations were performed on model trimers of 3-n-alkylthiophenes and show the relationship between regiochemistry of the trimer and its resultant conformations.The results of these calculations are related to the resultant electrical conductivity in these materials.These poly(3-alkylthiophenes) provide for the first time well-defined structures for the investigation of structure-property relationships in this class of electronic and photonic materials.
Controlling blend film morphology by varying alkyl side chain in highly coplanar donor-acceptor copolymers for photovoltaic application
Li, Yaowen,Chen, Yujin,Liu, Xing,Wang, Zhong,Yang, Xiaoming,Tu, Yingfeng,Zhu, Xiulin
, p. 6370 - 6381 (2011)
A series of varied length alkyl substituted donor-acceptor (D-A) conjugated copolymers with benzo[1,2-b:4,5-b′]dithiophene (BDT) as donor and thiophene rings attached to both sides of the benzothiadiazole (TBT) moieties as acceptors were designed and synthesized. The optical and electrochemical properties showed that the absorption spectrum, the band gaps, and the energy levels of the copolymers were not affected by the varied substituted alkyls, and all these copolymers showed low band gaps around 1.75 eV. In addition, the morphologies of the blend film between copolymers and PCBM can be fine-tuned by increasing the length of substituted alkyl of the copolymers, changing from pea-like aggregation to interpenetrating network to grain-like aggregation. Bulk heterojunction photovoltaic devices were fabricated by using the copolymers as donors and (6,6)-phenyl C61-butyric acid methyl ester (PC 61BM) or (6,6)-phenyl C71-butyric acid methyl ester (PC71BM) as acceptors. The optimized photovoltaic performances showed the stable open-circuit voltage (Voc) in the range of 0.68 to 0.74 eV, and dramatically increasing short circuit current density (Jsc) by optimizing the blending morphologies of copolymer and PCBM films. The optimized photovoltaic performance with a Voc of 0.70 V, J sc of 7.19 mA/cm2, a fill factor (FF) of 0.52, and a power conversion efficiency (PCE) of 2.88%, was obtained by the copolymer PBDT-TBT-C8 (PBDT-TBT-C8:PC61BM, 1:3 w/w, in CB solution). This is due to its low band gap and interpenetrating network morphology of PBDT-TBT-C8:PC 61BM blend film. The photovoltaic device based on PBDT-TBT-C8:PC 71BM showed a Jsc of 8.6 mA/cm2 and a PCE of 3.15%.
Organic Thin-film Solar Cells Using Benzotrithiophene Derivatives Bearing Acceptor Units as Non-Fullerene Acceptors
Matsumoto, Kouichi,Yamashita, Kazuhiro,Sakoda, Yuuki,Ezoe, Hinata,Tanaka, Yuki,Okazaki, Tatsuya,Ohkita, Misaki,Tanaka, Senku,Aoki, Yuki,Kiriya, Daisuke,Kashimura, Shigenori,Maekawa, Masahiko,Kuroda-Sowa, Takayoshi,Okubo, Takashi
, p. 4620 - 4629 (2021/09/10)
New star-shaped non-fullerene acceptors (5Z,5′Z,5′′Z)-5,5′,5′′-((benzo[1,2-b : 3,4-b′ : 5,6-b′′]trithiophene-2,5,8-triyltris(4-octylthiophene-5,2-diyl))tris(methaneylylidene))tris(3-octyl-2-thioxothiazolidin-4-one) (1: BTT-OT-ORD) and 2,2′,2′′-((5Z,5′Z,5′′Z)-((benzo[1,2-b : 3,4-b′ : 5,6-b′′]trithiophene-2,5,8-triyltris(4-octylthiophene-5,2-diyl))tris(methaneylylidene))tris(3-octyl-4-oxothiazolidine-5,2-diylidene))trimalononitrile (2: BTT-OT-OTZDM) with a benzotrithiophene core, alkyl-thiophen units, and acceptor units were designed and synthesized. The HOMO-LUMO levels of 1 and 2 were determined by photoemission spectroscopy and UV-Vis absorption spectroscopy. Binary blend and ternary blend bulk heterojunction (BHJ) organic solar cells with non-fullerene acceptors 1 and 2 were fabricated with the inverted device structures of glass/ITO/ZnO/active_layer/MoO3/Ag. Both binary blend BHJ solar cells with 1 and 2 show lower JSC and larger VOC values than P3HT : PCBM solar cells. On the other hand, ternary blend BHJ organic solar cells, including 10 % of 1, exhibited a larger power conversion efficiency than P3HT : PCBM solar cells because the JSC value was largely improved.
Thiophene-benzothiadiazole based donor–acceptor–donor (D-A-D) bolaamphiphiles, self-assembly and photophysical properties
Chang, Qing,Cheng, Xiaohong,Ding, Wei,Ma, Tao,Zhang, Lin
, (2021/11/03)
Bolaamphiphilies with D-A-D type π-conjugated rigid cores composed by thiophenes as donors (D) and benzothiadiazole (BTD) as central acceptor (A) have been synthesised. Their self-assemblies and photophysical properties were investigated by polarising optical microscope, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. Such compounds can self-assemble into honeycomb cylinder mesophases with Colhex?/p6mm and Colsqu/p4mm lattices in their pure states as well as organogels with different morphologies in organic solvents. Their absorption spectra cover nearly the entire visible light range and their band gaps are relatively low. Tetrathiophene BTD based bolaamphilphiles (BT4/n) with higher D/A ratios than the bisthiophene BTD bolaamphilphiles (BT2/n) can self-assemble into more ordered nanostructures in both bulk states and solution. Both the absorption and emission peaks of BT4/n are strongly red shifted. The influence of the molecular conformation, the conjugated core length, as well as the D/A ratio on the self-assemble and photophysical characteristics of such D-A-D bolaamphiphiles are discussed.
