Tag: 200-300

Multicolor Self-Assembled Fluorene Co-Oligomers: From Molecules to the Solid State via White-Light-Emitting Organogels was written by Abbel, Robert;van der Weegen, Rob;Pisula, Wojciech;Surin, Mathieu;Leclere, Philippe;Lazzaroni, Roberto;Meijer, E. W.;Schenning, Albertus P. H. J.. And the article was included in Chemistry – A European Journal in 2009.Synthetic Route of C8H4Br2N2 This article mentions the following:

Five fluorene-based co-oligomers were prepared and the self-assembly was studied in a wide range of concentrations, from dilute solutions to the solid state. Subtle changes to the chem. structure, introduced to tune the emission colors over the entire visible range, induce strong differences in aggregation. Only two of the fluorescent co-oligomer derivatives self-assemble to form soluble fibrils from which fluorescent organogels emerge at higher concentrations In contrast, the other compounds form precipitates Mixed fluorescent co-oligomer systems exhibit partial energy transfer, which allows the creation of white-light-emitting gels. A mechanism for the hierarchical self-assembly of the fluorene oligomers is proposed based on exptl. results and mol. modeling calculations In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Synthetic Route of C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.Synthetic Route of C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

D-A-π-A featured sensitizers by modification of auxiliary acceptor for preventing “trade-off” effect was written by Zhu, Haibo;Liu, Bo;Liu, Jingchuan;Zhang, Weiwei;Zhu, Wei-Hong. And the article was included in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices in 2015.COA of Formula: C8H4Br2N2 This article mentions the following:

Four D-A-π-A motif organic sensitizers (IQ9, IQ10, IQ11, and IQ12) in the absence or presence of thiophene substituents grafted onto the auxiliary acceptor of a quinoxaline unit were developed for dye sensitized solar cells (DSSCsa). Upon changing the π-linker from benzene to thiophene, the photocurrent (J_sc) of IQ10 increases around 2-fold, and the photovoltage (V_oc) decreases by 52 mV compared to that of IQ9. It is attributed to the fact that compared with the benzene linker, the thiophene conjugated bridge in dye IQ10 induces a small twist in the mol. planarity, thus resulting in the high light-harvesting capability (beneficial to J_sc) and high charge recombination (unbeneficial to V_oc). To prevent this trade-off effect between photocurrent and photovoltage, the building block of 2,3-dithienylquinoxaline as an auxiliary unit is specifically incorporated, which brings forth several advantages such as distinctly extending the light-harvesting region, increasing molar absorption coefficients, and blocking the dye self-aggregation to reduce charge recombination. Remarkably, dye IQ12 exhibits a beneficial balance between J_sc (17.97 mA cm^-2) and V_oc (715 mV), along with a promising photovoltaic efficiency of 8.76%, much better than the corresponding dyes IQ9 (2.91%), IQ10 (7.75%) and IQ11 (6.56%). As demonstrated, the two twisted thiophene groups grafted onto the quinoxaline unit facilitate the resulting compact sensitizer layer to effectively overcome the charge recombination drawbacks in V_oc arising from the thiophene π-bridge linker, providing a rational mol. engineering to pursue the synergistic enhancement in the photocurrent and photovoltage for highly efficient organic sensitizers. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3COA of Formula: C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.COA of Formula: C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Toward a Rational Design of Poly(2,7-Carbazole) Derivatives for Solar Cells was written by Blouin, Nicolas;Michaud, Alexandre;Gendron, David;Wakim, Salem;Blair, Emily;Neagu-Plesu, Rodica;Belletete, Michel;Durocher, Gilles;Tao, Ye;Leclerc, Mario. And the article was included in Journal of the American Chemical Society in 2008.Category: pyrazines This article mentions the following:

From theor. models and calculations, several alternating polymeric structures were studied to develop optimized poly(2,7-carbazole) derivatives for solar cell applications. Selected low band gap alternating copolymers were obtained via a Suzuki coupling reaction. A good correlation between DFT theor. calculations performed on model compounds and the exptl. HOMO, LUMO, and band gap energies of the corresponding polymers was obtained. This study reveals that the alternating copolymer HOMO energy level is mainly fixed by the carbazole moiety, whereas the LUMO energy level is mainly related to the nature of the electron-withdrawing comonomer. However, solar cell performances are not solely driven by the energy levels of the materials. Clearly, the mol. weight and the overall organization of the polymers are other important key parameters to consider when developing new polymers for solar cells. Preliminary measurements revealed hole mobilities of ∼1 × 10^-3 cm²/V-s and a power conversion efficiency (PCE) up to 3.6%. Further improvements are anticipated through a rational design of new sym. low band gap poly(2,7-carbazole) derivatives In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Category: pyrazines).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Category: pyrazines

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electronic structure of small band gap oligomers based on cyclopentadithiophenes and acceptor units was written by Karsten, Bram P.;Bijleveld, Johannes C.;Viani, Lucas;Cornil, Jerome;Gierschner, Johannes;Janssen, Rene A. J.. And the article was included in Journal of Materials Chemistry in 2009.Related Products of 148231-12-3 This article mentions the following:

A combined exptl. and theor. study was carried out on a series of well-defined small band gap oligomers. The cyclopentadithiophene oligomers were prepared by Suzuki coupling of thiopheneboronic esters and dibromophenylquinoxaline compounds These oligomers comprise two terminal electron-rich cyclopentadithiophene units connected to six different electron deficient aromatic rings that allow tuning the optical band gap from 1.4 to 2.0 eV. The optical absorption of the ground state, triplet excited state, and radical cation was studied. The optical band gap correlates with the electrochem. oxidation and reduction potential and is further supported by quantum-chem. calculations at the d. functional theory (DFT) level. The optical absorption of the radical cations shows only little variations among the different oligomers, suggesting that the charge is mainly localized on the donor moieties. Triplet energy levels are generally low (<1.2 eV) and the singlet-triplet splitting remains significant when going to smaller band gaps. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Related Products of 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Related Products of 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

New quinoxaline derivatives as accepting units in donor-acceptor type low-band gap polymers for organic photovoltaic cells was written by Kim, Ji-Hoon;Song, Chang Eun;Kim, Hee Un;Kang, In-Nam;Shin, Won Suk;Park, Moo-Jin;Hwang, Do-Hoon. And the article was included in Journal of Polymer Science, Part A: Polymer Chemistry in 2013.Computed Properties of C8H4Br2N2 This article mentions the following:

A series of new donor-acceptor-type low-band-gap semiconducting polymers were synthesized as electron donors for organic photovoltaic cells. The polymers comprised quinoxaline derivatives as the acceptors and a benzodithiophene (BDT) derivative as the donors. 5,8-Dibromoquinoxaline (Qx), 8,11-dibromobenzo[a]phenazine (BPz), 10,13-dibromodibenzo[a,c]phenazine (DBPz), and 8,11-dibromo-5-(9H-carbazol-9-yl)benzo[a]phenazine (CBPz) were synthesized and polymerized with 2,6-bis(trimethyltin)-4,8-diethylhexyloxybenzo-[1,2-b;3,4-b]dithiophene (BDT) through Stille cross-coupling to produce four types of fully conjugated semiconducting polymers: PBDT-Qx, PBDT-BPz, PBDT-DBPz, and PBDT-CBPz, resp. Intramol. charge transfer between the electron donating and accepting units in the polymeric backbone induced a broad absorption from 300 to 800 nm. The optical band gap energies of the polymers were measured from their absorption onsets to be 1.54-1.80 eV depending on the polymer structure. Solution-processed field-effect transistors were fabricated to measure the hole mobilities of the polymers, and bulk hetero-junction photovoltaic devices were fabricated using the synthesized polymers as electron donors and fullerene derivatives as electron acceptors. One of these devices showed a high power conversion efficiency of 3.87% with an open-circuit voltage of 0.78 V, a short-circuit current of 9.68 mA/Cm², and a fill factor of 0.51 under air mass 1.5 global (AM 1.5 G) illumination conditions (100 mW/Cm²). © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Computed Properties of C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, α-hydroxyketone, α-methyl ketone. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Computed Properties of C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Molecular 5,8-π-extended quinoxaline derivatives as chromophores for photoluminescence applications was written by Aguiar, Leonardo de O.;Junior, Adalberto S. L.;Bechtold, Ivan H.;Curcio, Sergio Fernando;Cazati, Thiago;Alves, Tiago V.;Vieira, Andre Alexandre. And the article was included in Journal of Molecular Liquids in 2019.Reference of 148231-12-3 This article mentions the following:

The 5,8-π-extended quinoxaline derivatives are widely studied due to their well-known photophys. and electrochem. properties. In order to investigate the structure-property relationship, a novel series of fluorescent calamitic liquid crystals based on the quinoxaline heterocycle was successfully synthesized and characterized. The final mols. presented calamitic mesomorphism with nematic and smectic phases. These compounds displayed intense green photoluminescence under UV light excitation in solution and in the solid state. In chloroform solution, the fluorescence quantum yields (Φ_FL = 0.54-0.62) of the quinoxaline-based derivatives were significantly higher than those previously described for similar benzothiadiazoles. The maximum emission peaks were between 511 and 520 nm with singlet excited-state lifetimes in the nanosecond timescale. The solvatochromism studies showed a significant dependence of the emission on the polarity of the solvent. Doping of the quinoxalines with fullerene C₆₀ suggests a charge transfer process, this being dependent on the π-conjugate core. The energy band gaps predicted with DFT calculations are in excellent agreement with the exptl. data. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Reference of 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Reference of 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Surface self-assembly involving the interaction between S and N atoms was written by Wu, Tianhao;Xue, Na;Wang, Zhichao;Li, Jie;Li, Yaru;Huang, Wei;Shen, Qian;Hou, Shimin;Wang, Yongfeng. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2021.Quality Control of 5,8-Dibromoquinoxaline This article mentions the following:

Controllable mol. self-assembly is vital for nanostructure construction. Here, three different self-assembling networks are realized by varying the chem. composition of the mol. building blocks of the same architecture. This is the first time that S···N electrostatic attraction has been employed to regulate surface self-assembly. All mol. structures are characterized using low-temperature scanning tunnelling microscopy. The d. functional theory calculations elaborate the structure formation mechanism. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Quality Control of 5,8-Dibromoquinoxaline).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Quality Control of 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Discovery of potent colony-stimulating factor 1 receptor inhibitors by replacement of hinge-binder moieties was written by Lee, Jung Wuk;Park, Jiwon;Kim, Jina;Kim, Jihyung;Choi, Changyu;Min, Kyung Hoon. And the article was included in European Journal of Medicinal Chemistry in 2021.HPLC of Formula: 1150566-27-0 This article mentions the following:

Tumor-associated macrophages (TAMs) are predominantly associated with tumor growth. Colony-stimulating factor 1 receptor (CSF1R) acts as a key regulator of TAM survival and differentiation and is a mol. target for cancer therapies. Herein, novel CSF1R inhibitors were identified through a replacement strategy for the hinge-binding moiety. The introduction of imidazo[1,2-a]pyridine I or pyrazolo[1,5-a]pyridine II as hinge binders led to 87% and 82% inhibition at 10 nM for CSF1R in the enzymic assay, with IC₅₀ values of 25 nM and 27 nM in MNFS60 cells, resp. These derivatives significantly inhibited CSF1R phosphorylation in cells. Author approach could be utilized as a strategy to discover novel kinase inhibitors. In the experiment, the researchers used many compounds, for example, Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0HPLC of Formula: 1150566-27-0).

Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.HPLC of Formula: 1150566-27-0

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Conjugated microporous polymers as heterogeneous photocatalysts for efficient degradation of a mustard-gas simulant was written by Zhi, Yongfeng;Yao, Zhengjie;Jiang, Wenbo;Xia, Hong;Shi, Zhan;Mu, Ying;Liu, Xiaoming. And the article was included in ACS Applied Materials & Interfaces in 2019.Name: 5,8-Dibromoquinoxaline This article mentions the following:

Compared with traditional metal-based photosensitizers, heterogeneous and organic photocatalysts with visible-light activity are more environmentally friendly and sustainable. The simultaneous introduction of electron-rich and electron-deficient units in donor-acceptor typed conjugated microporous polymer (CMP) photocatalysts can significantly enhance their visible-light harvesting and separation efficiency of photogenerated carriers. Here, two carbazole-based CMPs (CzBSe-CMP and CzBQn-CMP) were successfully constructed through a cost-effective process. They show inherent porosity with large Brunauer-Emmett-Teller surface area and excellent thermal and chem. stability. Their photoelec. properties, energy levels, optical band gaps, transient photocurrent response, and photocatalytic activity could be conveniently tailored through tuning the electron-deficient moiety in polymer networks. More importantly, CzBSe-CMP was found to be a superior solid photocatalyst for selective photo-oxidation of mustard gas simulant 2-chloroethyl Et sulfide into a nontoxic product by using mol. oxygen as a sustainable oxygen source under visible-light illumination. In addition, the obtained CMP-based photocatalysts also showed excellent recyclability and could be reutilized through adding more simulants or a simple separation procedure. The current contribution provides great application prospects for CMPs as metal-free, solid photocatalysts in organic transformation and environmental protection. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Name: 5,8-Dibromoquinoxaline).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Name: 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Fluorescence Modulation of Conjugated Polymer Nanoparticles Embedded in Poly(N-Isopropylacrylamide) Hydrogel was written by Namgung, Ho;Jo, Seonyoung;Lee, Taek Seung. And the article was included in Polymers (Basel, Switzerland) in 2021.Application In Synthesis of 5,8-Dibromoquinoxaline This article mentions the following:

A series of conjugated polymers (CPs) emitting red, green, and blue (RGB) fluorescence were synthesized via the Suzuki coupling polymerization Polymer dots (Pdots) were fabricated by the reprecipitation method from corresponding CPs, in which the Pdot surface was functionalized to have an allyl moiety. The CP backbones were based on the phenylene group, causing the Pdots to show identical UV-visible absorption at 350 nm, indicating that the same excitation wavelength could be used. The Pdots were covalently embedded in poly(N-isopropylacrylamide) (PNIPAM) hydrogel for further use as a thermoresponsive moiety in the polymer hydrogel. The polymer hydrogel with RGB emission colors could provide thermally reversible fluorescence changes. The size of the hydrogel varied with temperature change because of the PNIPAM’s shrinking and swelling. The swollen and contracted conformations of the Pdot-embedded PNIPAM enabled on-and-off fluorescence, resp. Fluorescence modulation with 20 to 80% of the hydrogel was possible via thermoreversibility. The fluorescent hydrogel could be a new fluorescence-tuning hybrid material that changes with temperature In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Application In Synthesis of 5,8-Dibromoquinoxaline).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Application In Synthesis of 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem