891-22-5Relevant academic research and scientific papers
Arylaliphatic 3-aza-1,5-diketones: Reactions with N-nucleophiles
Akimova,Trofimenko,Ivanenko
, p. 1346 - 1348 (2003)
1-Substituted 3,5-diphenylpyrazinium salts were obtained by reactions of tertiary bis(phenacyl)-amines with ammonium acetate, hydroxylamine hydrochloride, and hydrazine hydrate in acid medium. The reaction of quaternary dimethylbis(phenacyl)ammonium bromi
Non-interlayer and color stable WOLEDs with mixed host and incorporating a new orange phosphorescent iridium complex
Guo, Li-Yuan,Zhang, Xun-Lu,Zhuo, Min-Jie,Liu, Chen,Chen, Wang-Yang,Mi, Bao-Xiu,Song, Juan,Li, Yong-Hua,Gao, Zhi-Qiang
, p. 2964 - 2970 (2014)
In this work, we have synthesized a new phosphorescent iridium complex (Bppya)2Ir(acac), as an orange dopant for organic light-emitting diodes (OLEDs). The device achieved an external quantum efficiency (EQE) of 22.4%, a current efficiency of 49.5 cd A-1and a power efficiency of 38.9 lm W-1, which are among the highest values for orange OLEDs. Furthermore, color stable and high efficiency phosphorescent white OLED (WOLED) was demonstrated by utilizing a mixed-host in the emissive layers (EMLs) composed of a blue phosphor and the new orange phosphorescent emitter, as well as by avoiding the use of interlayers that commonly exist between different EMLs in WOLEDs. Our WOLED presented decent white emission with maximum efficiencies of 25.3 cd A-1and 12.6%. Furthermore, the 1931 Commission Internationale de l'Eclairage color coordinates exhibited extremely small variation of (0.3940 ± 0.0102, 0.4323 ± 0.0046) in a wide luminance range from 49 to 38,035 cd m-2when driving voltages increased from 4 V to 12 V. The root cause for this excellent color stability is the utilization of the mixed-host to obtain bipolar transport properties in EMLs as well as the eliminating of interlayer between different EMLs, which, on one hand, effectively broaden the exciton recombination zone; on the other hand, reduce the accumulation of triplet excitons at the emissive interface.
Triphenylene analogues with B2N2C2 cores: Synthesis, structure, redox behavior, and photophysical properties
Jaska, Cory A.,Emslie, David J. H.,Bosdet, Michael J. D.,Piers, Warren E.,Sorensen, Ted S.,Parvez, Masood
, p. 10885 - 10896 (2006)
A series of alkyl (1-3), aryl (6), and benzo-annulated (4,5) heteroaromatic triphenylene analogues with B2N2C2 cores have been synthesized via chelation of pyridazine derivatives using difunctional Lewis acidic diborabiphenyl precursors. In contrast to triphenylene, NICS(1) calculations on 1 suggested high aromaticities for the central (-11.3 ppm) and outer borabenzene rings (-7.7 ppm), along with nonaromatic behavior for the pyridazine ring (-0.7 ppm). Crystal structure analyses supported this analysis. When the a- and c-faces of the pyridazine moiety were free of substitution (1, 3), planar structures resulted, but upon substitution, a twisted B 2N2C2 core was observed due to steric repulsion of neighboring hydrogen atoms (e.g., 5). The increase of steric bulk from H (1) to ′Pr (3) in the planar species was found to result in a dimeric, head-to-tail herringbone packing motif, held together by close intermolecular B...N interactions of 3.39 A. One-electron reduction by Cp*2Co was found to afford the radical anions of 3 and 5, which were characterized by broad, featureless singlets in the EPR spectra; [3] .-[Cp*2Co]- was characterized by X-ray crystallography. While the planar structures (1-4) were observed to possess weak fluorescence (ΦF = 0.02-0.08) with either yellow-orange (ca. 555 nm) or green emission (521 nm), the twisted structures (5, 6) were found to be nonfluorescent.
Vinyl Azides as Radical Acceptors in the Vitamin B12-Catalyzed Synthesis of Unsymmetrical Ketones
Dworakowski, Krzysztof R.,Pisarek, Sabina,Hassan, Sidra,Gryko, Dorota
supporting information, p. 9068 - 9072 (2021/11/30)
Vinyl azides are very reactive species and as such are useful building blocks, in particular, in the synthesis of N-heterocycles. They can also serve as precursors of ketones. These form in reactions of vinyl azides with nucleophiles or radicals. We have found, however, that under light irradiation vitamin B12 catalyzes the reaction of vinyl azides with electrophiles to afford unsymmetrical carbonyl compounds in decent yields. Mechanistic studies revealed that alkyl radicals are key intermediates in this transformation.
One-Pot and Two-Chamber Methodologies for Using Acetylene Surrogates in the Synthesis of Pyridazines and Their D-Labeled Derivatives
Ananikov, Valentine P.,Ledovskaya, Maria S.,Polynski, Mikhail V.
, p. 2286 - 2297 (2021/07/20)
Acetylene surrogates are efficient tools in modern organic chemistry with largely unexplored potential in the construction of heterocyclic cores. Two novel synthetic paths to 3,6-disubstituted pyridazines were proposed using readily available acetylene surrogates through flexible C2 unit installation procedures in a common reaction space mode (one-pot) and distributed reaction space mode (two-chamber): (1) an interaction of 1,2,4,5-tetrazine and its acceptor-functionalized derivatives with a CaC2?H2O mixture performed in a two-chamber reactor led to the corresponding pyridazines in quantitative yields; (2) [4+2] cycloaddition of 1,2,4,5-tetrazines to benzyl vinyl ether can be considered a universal synthetic path to a wide range of pyridazines. Replacing water with D2O and vinyl ether with its trideuterated analog in the developed procedures, a range of 4,5-dideuteropyridazines of 95–99% deuteration degree was synthesized for the first time. Quantum chemical modeling allowed to quantify the substituent effect in both synthetic pathways.
A green and practical one-pot two-step strategy for the synthesis of symmetric 3,6-diarylpyridazines
Rimaz, Mehdi,Mousavi, Hossein,Khalili, Behzad,Aali, Farkhondeh
, p. 1389 - 1397 (2018/11/26)
A simple, mild, and efficient synthesis of symmetric 3,6-diarylpyridazine derivatives using a green catalytic one-pot two-step reaction of aryl methyl ketones, arylglyoxal monohydrates, and hydrazine hydrate was developed. Environmentally benign nature, high atom-economy, no harmful byproduct, easy workup procedure, no column chromatography steps, and moderate to excellent yields of the products are the salient features of this new multicomponent-based methodology.
Efficient Suzuki-Miyaura mono-arylation of symmetrical diiodo(hetero)arenes
Sapegin, Alexander,Krasavin, Mikhail
supporting information, p. 1948 - 1951 (2018/04/16)
A reliable protocol for converting 1,4-diiodo-2,3,5,6-tetrafluorobenzene into 1-(hetero)aryl-4-iodo-2,3,5,6-tetrafluorobenzene derivatives has been lacking in the literature. We have identified optimal conditions to achieve this conversion in good yields and have minimized formation of the bis-coupling product. The newly identified protocol involving the use of a syringe pump has been extended to other symmetrical diiodo(hetero)arenes.
B(C6F5)3-catalyzed metal-free hydrogenation of 3,6-diarylpyridazines
Wang, Wei,Meng, Wei,Du, Haifeng
supporting information, p. 5945 - 5948 (2016/04/26)
This paper describes the first metal-free hydrogenation of 3,6-diarylpyridazines, which was successfully realized using B(C6F5)3 as a catalyst. A variety of 1,4,5,6-tetrahydropyridazine derivatives were furnished in 85-95%
A general catalyst for Suzuki-Miyaura and Sonogashira reactions of aryl and heteroaryl chlorides in water
Peng, Hui,Chen, Ya-Qin,Mao, Shu-Lan,Pi, Yun-Xiao,Chen, You,Lian, Ze-Yu,Meng, Tong,Liu, Sheng-Hua,Yu, Guang-Ao
supporting information, p. 6944 - 6952 (2014/09/29)
We report the synthesis of 2-(3-sulfonatomesityl)-5-sulfonatoindenyl) dicyclohexylphosphine hydrate sodium salt and its use in palladium-catalyzed Suzuki-Miyaura and Sonogashira coupling reactions in water (and biphasic water-organic solvent mixtures) to prepare a variety of functionalized biaryls and aryl alkynes in excellent yield. This journal is the Partner Organisations 2014.
Non-interlayer and color stable WOLEDs with mixed host and incorporating a new orange phosphorescent iridium complex
Guo, Li-Yuan,Zhang, Xun-Lu,Zhuo, Min-Jie,Liu, Chen,Chen, Wang-Yang,Mi, Bao-Xiu,Song, Juan,Li, Yong-Hua,Gao, Zhi-Qiang
, p. 2964 - 2970 (2014/12/11)
In this work, we have synthesized a new phosphorescent iridium complex (Bppya)2Ir(acac), as an orange dopant for organic light-emitting diodes (OLEDs). The device achieved an external quantum efficiency (EQE) of 22.4%, a current efficiency of 49.5 cd A-1 and a power efficiency of 38.9 lmW-1, which are among the highest values for orange OLEDs. Furthermore, color stable and high efficiency phosphorescent white OLED (WOLED) was demonstrated by utilizing a mixed-host in the emissive layers (EMLs) composed of a blue phosphor and the new orange phosphorescent emitter, as well as by avoiding the use of interlayers that commonly exist between different EMLs in WOLEDs. Our WOLED presented decent white emission with maximum efficiencies of 25.3 cd A-1 and 12.6%. Furthermore, the 1931 Commission Internationale de l'Eclairage color coordinates exhibited extremely small variation of (0.3940 ± 0.0102, 0.4323 ± 0.0046) in a wide luminance range from 49 to 38,035 cd m-2 when driving voltages increased from 4 V to 12 V. The root cause for this excellent color stability is the utilization of the mixed-host to obtain bipolar transport properties in EMLs as well as the eliminating of interlayer between different EMLs, which, on one hand, effectively broaden the exciton recombination zone; on the other hand, reduce the accumulation of triplet excitons at the emissive interface.
