Tag: M.W=300-350

Wang, Zhiming published the artcileHighly π-extended polymers based on phenanthro-pyrazine: Synthesis, characterization, theoretical calculation and photovoltaic properties, Formula: C4Br2N2O4S, the publication is Polymer (2013), 54(22), 6191-6199, database is CAplus.

Two novel narrow bandgap conjugated polymers containing phenanthro-pyrazine unit have been successfully synthesized by the Stille coupling reaction. Comparing to the common polymers containing dithiophen-quinoxaline or dithiophen-thieno[3,4-b]pyrazine moiety, the conjugation degree of these new polymers is extended through the direction perpendicular to the main chain by introducing phenanthrene-9,10-dione to maintain a rigid conjugated bridge. The obtained polymers exhibit solution-processing ability, high thermal stabilities, broad visible absorption bands and narrow optical bandgaps. Theor. studies disclose that the P2 exhibits wholly coplanar conformation in 1-D and 2-D direction, and the PCE value is 6-folded higher than P1 under the same photovoltaic measurement condition.

Polymer published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C13H26N2, Formula: C4Br2N2O4S.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Galli, Diana published the artcileSuppressing the Surface Recombination and Tuning the Open-Circuit Voltage of Polymer/Fullerene Solar Cells by Implementing an Aggregative Ternary Compound, Safety of 2,5-Dibromo-3,4-dinitrothiophene, the publication is ACS Applied Materials & Interfaces (2018), 10(34), 28803-28811, database is CAplus and MEDLINE.

The authors present a novel small mol. based on dithienylthienothiadiazole units (named SM1) acting as an efficient component in ternary blend organic solar cells to modify the hole extraction at the interface. The SM1 suppresses the surface recombination and enhances the open-circuit voltage (V_oc). By introducing SM1 in a host system composed of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C₆₁-butyric acid Me ester (PCBM), the authors obtained V_oc values of up to 0.75 V and fill factors larger than 70% for the ternary blends. As a consequence, the power conversion efficiency is improved by ∼30% compared to P3HT:PCBM binary devices. External quantum efficiency and absorption spectra in the near-IR region do not show any contribution of SM1 in dried films. Instead, the addition of the small mol. improves the V_oc by reducing the surface recombination losses. To shed light on the recombination processes, the authors carried out Fourier-transform photocurrent spectroscopy and impedance spectroscopy measurements. The ternary concept can also have functionalities other than photosensitization and can even act as a morphol.-directing agent or an interface modifier.

ACS Applied Materials & Interfaces published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, Safety of 2,5-Dibromo-3,4-dinitrothiophene.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Zhong, Yongliang published the artcileFunctionalized Polyesters via Stereoselective Electrochemical Ring-Opening Polymerization of O-Carboxyanhydrides, Recommanded Product: Cobalt(II) dibromo(1,2-dimethoxyethane), the publication is ACS Macro Letters (2020), 9(8), 1114-1118, database is CAplus and MEDLINE.

Ring-opening polymerization is used to prepare polyesters with precisely controlled mol. weights, mol. weight distributions, and tacticities. Herein, we report a Co/Zn catalytic system that can be activated by an elec. current to mediate efficient ring-opening polymerization of enantiopure O-carboxyanhydrides, allowing for the synthesis of isotactic functionalized polyesters with high mol. weights (>140 kDa) and narrow mol. weight distributions (M_w/M_n < 1.1). We also demonstrate that these catalysts can be used for stereoselective ring-opening polymerization of racemic O-carboxyanhydrides to synthesize syndiotactic or stereoblock copolymers with different glass transition temperatures compared with their atactic counterparts.

ACS Macro Letters published new progress about 18346-57-1. 18346-57-1 belongs to bromides-buliding-blocks, auxiliary class Cobalt, name is Cobalt(II) dibromo(1,2-dimethoxyethane), and the molecular formula is C18H10F3NO3S2, Recommanded Product: Cobalt(II) dibromo(1,2-dimethoxyethane).

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Li, Penglei published the artcileDual functions of a novel low-gap polymer for near infra-red photovoltaics and light-emitting diodes, Safety of 2,5-Dibromo-3,4-dinitrothiophene, the publication is Chemical Communications (Cambridge, United Kingdom) (2011), 47(31), 8820-8822, database is CAplus and MEDLINE.

We have synthesized and characterized a new low-gap conjugated polymer, with a broad absorption profile. In blends with a C₇₀ derivative we demonstrate power conversion efficiencies of 0.76%. We show electroluminescence from the polymer peaking at 956 nm, and quantum efficiency of 0.02% in a blend.

Chemical Communications (Cambridge, United Kingdom) published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, Safety of 2,5-Dibromo-3,4-dinitrothiophene.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Zoombelt, Arjan P. published the artcileSynthesis and photovoltaic performance of a series of small band gap polymers, Recommanded Product: 2,5-Dibromo-3,4-dinitrothiophene, the publication is Journal of Materials Chemistry (2009), 19(30), 5336-5342, database is CAplus.

A series of four small band gap polymers have been synthesized and have been incorporated into bulk heterojunction solar cells. The polymers were prepared via Yamamoto coupling and consist of alternating electron-rich dithiophene and electron-deficient bisquinoxaline or thienopyrazine units. In the thin solid films the optical band gaps vary from 1.38 eV for the bisquinoxaline to 1.21 eV for thienopyrazine containing polymers. All polymers provide a photovoltaic response when blended with a methanofullerene as electron acceptor in the near-IR region up to the optical band gap. The best cells reach an efficiency of 1.5% under estimated standard solar light conditions (air-mass 1.5G, 100 mW/cm²).

Journal of Materials Chemistry published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C9H9BrO2, Recommanded Product: 2,5-Dibromo-3,4-dinitrothiophene.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Wiechmann, Sascha published the artcileSydnone anions and abnormal N-heterocyclic carbenes of O-ethylsydnones. Characterizations, calculations and catalyses, Category: bromides-buliding-blocks, the publication is Chemical Communications (Cambridge, United Kingdom) (2014), 50(80), 11822-11824, database is CAplus and MEDLINE.

Deprotonated sydnones, which can be represented as anionic N-heterocyclic carbenes, were prepared as Li adducts and compared with deprotonated O-ethylsydnones (5-ethoxy-1,2,3-oxadiazol-4-ylidenes) which belong to the class of abnormal NHCs. The Pd complexes of the sydnone anions (x-ray anal.) and of the O-ethylsydnone carbenes proved to be efficient catalysts in aryl couplings of thiophenes.

Chemical Communications (Cambridge, United Kingdom) published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C11H8O3, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Abdo, Nabiha I. published the artcilePalladium-Catalyzed Direct C-H Arylation of Thieno[3,4-b]pyrazines: Synthesis of Advanced Oligomeric and Polymeric Materials, COA of Formula: C4Br2N2O4S, the publication is European Journal of Organic Chemistry (2012), 2012(28), 5540-5551, S5540/1-S5540/37, database is CAplus.

The first examples are reported of an efficient direct regioselective direct C-H arylation of thieno[3,4-b]pyrazine (TP) and its 2,3-di-Me derivative with bromoalkylthiophenes (BATs), under Heck exptl. conditions using Pd(OAc)₂/Bu₄NBr as the catalytic system, giving rise to a variety of valuable aryl-substituted thienopyrazines. The obtained results suggested that the 2-position of the TP moiety is less reactive towards C-H arylation than the 5- and 7-positions. Moreover, the 3-position of the TP moiety showed almost no significant reactivity when all other positions were arylated. The C-H arylation of 2,3-dimethyl-TP with an excess amount of BATs proceeded smoothly, affording the corresponding diarylated thienopyrazine derivatives in excellent yields, without any addnl. products. Compared to usual cross-coupling reactions, the present synthetic methodol. has been used to prepare interesting donor-acceptor π-conjugated polymeric materials in a facial manner in a simple way. Microwave-assisted polymerization proved to be efficient for obtaining reasonable mol. weight copolymers ranging from 18.8 to 24.3 kg mol^-1. Incorporating the thienopyrazine unit into polyhexylthiophene chains affected the photophys. and electrochem. properties. The optical band gaps were estimated to be in the range of 1.63-1.06 eV. All copolymers exhibited a diffraction peak at around 2θ = 5.72° corresponding to a d spacing of 15.43 Å, which was assigned to an interchain spacing between polymer main chains similar to that found in P3HT. Moreover, a peak around 2θ = 23.09 (3.84 Å) was also observed and is believed to be related to π-π stacking of the polymer backbones.

European Journal of Organic Chemistry published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, COA of Formula: C4Br2N2O4S.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Herberich, Gerhard E. published the artcileBis(boryl)metallocenes. 2. Syntheses of 1,1′-Bis(boryl)cobaltocenium Complexes, Name: Cobalt(II) dibromo(1,2-dimethoxyethane), the publication is Organometallics (1998), 17(22), 4769-4775, database is CAplus.

Bis(boryl)cobaltocenes Co(C₅H₄BR₂)₂ (1) can be made from CoBr₂(DME) and alkali metal borylcyclopentadienides M(C₅H₄BR₂) (M = Li, Na) (2). The two dialkylamino compounds 1c (R = NMe₂) and 1d (R = NEt₂) can be obtained in this way. Oxidation with C₂Cl₆ provides the ionic cobaltocenium chlorides (1c)Cl and (1d)Cl. Further cobaltocenium compounds can be synthesized by modification of the substituents at B. Treatment of (1d)Cl with excess BCl₃ affords the highly reactive chloride Co(C₅H₄BCl₂)(C₅H₄BCl₃) (5). Pinacolysis of 5 then affords the monosubstitution product Co[C₅H₄B(OCMe₂)₂](C₅H₄BCl₃) (9) and the disubstitution product [Co{C₅H₄B(OCMe₂)₂}₂]Cl [(1h)Cl], resp., depending on stoichiometry and reaction conditions. Reaction of 5 with tetramethyltin replaces two Cl atoms with Me groups to give Co(C₅H₄BMe₂)(C₅H₄BCl₃) (10), while the more reactive trimethylaluminum replaces four Cl substituents to give [Co(C₅H₄BMe₂)₂]AlCl₄ [(1b)AlCl₄] and, after metathesis with NBu₄PF₆ in CH₂Cl₂, the more convenient hexafluorophosphate (1b)PF₆. The corresponding cobaltocene 1b is then accessible via conventional amalgam reduction of (1b)AlCl₄. Reaction of 5 with com. AsF₃ affords the robust inverse chelate Co(C₅H₄BF₂)₂(μ-OH) (11). Three structural types are encountered for the cobaltocenium derivatives: (i) ionic compounds (type A) such as (1c,d,h)Cl, (1b)AlCl₄, and (1b)PF₆; (ii) zwitterionic or semiquaternized compounds (type B) with one trigonal and one tetrahedral B center such as 5, 9, and 10; of these, 5 is fluxional in solution with two effectively equivalent ligands while 9 and 10 display static structures; and (iii) the inverse chelate structure of 11 (type C) which is found in the crystal and in solution The crystal and mol. structures of 11 were determined by x-ray crystallog.

Organometallics published new progress about 18346-57-1. 18346-57-1 belongs to bromides-buliding-blocks, auxiliary class Cobalt, name is Cobalt(II) dibromo(1,2-dimethoxyethane), and the molecular formula is C4H10Br2CoO2, Name: Cobalt(II) dibromo(1,2-dimethoxyethane).

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Lu, Xuefeng published the artcileControlling the Charge Transfer in D-A-D Chromophores Based on Pyrazine Derivatives, SDS of cas: 52431-30-8, the publication is Journal of Organic Chemistry (2014), 79(14), 6480-6489, database is CAplus and MEDLINE.

A series of sym. donor-acceptor-donor (D-A-D) chromophores bearing various electron-withdrawing groups, such as quinoxaline (Qx), benzo[g]quinoxaline (BQ), phenazine (Pz), benzo[b]phenazine (BP), thieno[3,4-b]pyrazine (TP), and thieno[3,4-b]quinoxaline (TQ), was designed and synthesized. Intramol. charge transfer (ICT) interactions can be found for all the chromophores due to the electron-withdrawing properties of the two imine nitrogens in the pyrazine ring and the electron-donating properties of the other two amine nitrogens in the two triphenylamines. Upon the fusion of either benzene or thiophene ring on the pyrazine acceptor unit, the ICT interactions are strengthened, which results in the bathochromically shifted ICT band. Moreover, the thiophene ring is superior to the benzene ring in enlarging the ICT interaction and expanding the absorption spectrum. Typically, when a thiophene ring is fused on the Qx unit in DQxD, a near-IR dye is realized in simple chromophore DTQD, which displays the maximum absorption wavelength at 716 nm with the threshold over 900 nm. This is probably due to the enhanced charge d. on the acceptor moiety and better orbital overlap, as revealed by theor. calculation These results suggest that extending the conjugation of a pyrazine acceptor in an orthogonal direction to the D-A-D backbone can dramatically improve the ICT interactions.

Journal of Organic Chemistry published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, SDS of cas: 52431-30-8.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Qi, Ji published the artcileSimultaneously boosting the conjugation, brightness and solubility of organic fluorophores by using AIEgens, Recommanded Product: 2,5-Dibromo-3,4-dinitrothiophene, the publication is Chemical Science (2020), 11(32), 8438-8447, database is CAplus and MEDLINE.

Organic near-IR (NIR) emitters hold great promise for biomedical applications. Yet, most organic NIR fluorophores face the limitations of short emission wavelengths, low brightness, unsatisfactory processability, and the aggregation-caused quenching effect. Therefore, development of effective mol. design strategies to improve these important properties at the same time is a highly pursued topic, but very challenging. Herein, aggregation-induced emission luminogens (AIEgens) are employed as substituents to simultaneously extend the conjugation length, boost the fluorescence quantum yield, and increase the solubility of organic NIR fluorophores, being favorable for biol. applications. A series of donor-acceptor type compounds with different substituent groups (i.e., hydrogen, Ph, and tetraphenylethene (TPE)) are synthesized and investigated. Compared to the other two analogs, MTPE-TP3 with TPE substituents exhibits the reddest fluorescence, highest brightness, and best solubility Both the conjugated structure and twisted conformation of TPE groups endow the resulting compounds with improved fluorescence properties and processability for biomedical applications. The in vitro and in vivo applications reveal that the NIR nanoparticles function as a potent probe for tumor imaging. This study would provide new insights into the development of efficient building blocks for improving the performance of organic NIR emitters.

Chemical Science published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, Recommanded Product: 2,5-Dibromo-3,4-dinitrothiophene.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary