365-24-2Relevant academic research and scientific papers
High triplet energy exciton blocking materials based on triphenylamine core for organic light-emitting diodes
Bagdziunas, Gintautas,Surka, Mindaugas,Ivaniuk, Khrystyna
, p. 122 - 129 (2017)
A series of novel high triplet energy materials have been designed and synthesized from the simple starting compounds through a simple one-step Friedel–Crafts reaction by using triphenylamine and methoxy, fluoro substituted diphenylmethanoles and triphenylmethanol as the starting materials. The synthesized compounds exhibit the ionization potentials in an interval of 5.4–5.7?eV in the solid state, the wide bang-gaps of 3.6?eV and the high triplet energies of about 3.0?eV. The photophysical properties have been confirmed by DFT. The introduction of a material with the lowest ionization potential as the high triplet energy exciton blocking thin layer of the green organic light-emitting diode doubled the quantum efficiency of the device. The best fabricated green device exhibited the maximum current, power, and external quantum efficiencies of 80.1?Cd?A?1 and 31.4?Lm?W?1, 23.2%, respectively. The triplet-triplet annihilation and triplet-polaron quenching effects for the devices without and with exciton blocking layer have been analyzed.
First catalytic enantioselective synthesis of the cocaine abuse therapeutic agent (S)-(+)-1-(4-{2-[bis(4-fluorophenyl)methoxy]ethyl}piperazin-1-yl)-2-phenyl-2-propanol
Forrat, Vicente J.,Ramon, Diego J.,Yus, Miguel
, p. 400 - 405 (2007)
(S)-(+)-1-(4-{2-[Bis(4-fluorophenyl)methoxy]ethyl}piperazin-1-yl)-2-phenyl-2-propanol, which is a promising candidate as a cocaine abuse therapeutic agent, is prepared in several steps. The key asymmetric step is the catalytic enantioselective addition of dimethylzinc to either 2-chloro or 2-bromoacetophenone catalyzed by the use of different chiral isoborneolsulfonamide ligands in the presence of titanium tetraisopropoxide. The synthesis of a new isoborneolsulfonamide ligand bearing a trifluromethyl substituent and its use in this addition is also presented.
Light-driven MPV-type reduction of aryl ketones/aldehydes to alcohols with isopropanol under mild conditions
Cao, Dawei,Xia, Shumei,Pan, Pan,Zeng, Huiying,Li, Chao-Jun,Peng, Yong
supporting information, p. 7539 - 7543 (2021/10/12)
Alcohols are versatile structural motifs of pharmaceuticals, agrochemicals and fine chemicals. With respect to green chemistry, the development of more sustainable and cost-efficient processes for converting ketones/aldehydes to alcohols is highly desired. Herein, a direct light-driven strategy for reducing ketones/aldehydes to alcohols using isopropanol as the reducing agent and solvent, in the presence of t-BuOLi, under an air atmosphere at room temperature is developed. This operationally simple light-promoted Meerwein-Ponndorf-Verley (MPV) type reduction can be used to produce various benzylic alcohol derivatives as well as applied to bioactive molecules and PEEK model compounds, demonstrating its application potential.
MAGL inhibitor as well as preparation method and application thereof
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Paragraph 0027-0029, (2021/03/30)
The invention relates to a compound shown as a formula I in the description and a pharmaceutically acceptable salt thereof, a preparation method, an intermediate for preparing the compound, a composition containing the compound or salt, and application of the compound for preparing drugs for treating MAGL-mediated diseases and symptoms.
Simple synthesis of [Ru(CO3)(NHC)(p-cymene)] complexes and their use in transfer hydrogenation catalysis
Cazin, Catherine S. J.,Guillet, Sébastien G.,Liu, Yaxu,Ma, Xinyuan,Nolan, Steven P.
, p. 13012 - 13019 (2021/10/12)
A novel, efficient and facile protocol for the synthesis of a series of [Ru(NHC)(CO3)(p-cymene)] complexes is reported. This family of Ru-NHC complexes was obtained from imidazol(in)ium tetrafluoroborate or imidazolium hydrogen carbonate salts in moderate to excellent yields, employing sustainable weak base. The ruthenium complexes were successfully utilized in the transfer hydrogenation of ketones as highly active multifunctional catalysts.
Formation of a hydride containing amido-zincate using pinacolborane
Ingleson, Michael J.,Nichol, Gary S.,Uzelac, Marina,Yuan, Kang
supporting information, p. 14018 - 14026 (2021/10/19)
Amido-zincates containing hydrides are underexplored yet potentially useful complexes. Attempts to access this type of zincate through combining amido-organo zincates and pinacolborane (HBPin)viaZn-C/H-BPin exchange led instead to preferential formation of amide-BPin and/or [amide-BPin(Y)]?(Y = Ph, amide, H), when the amide is hexamethyldisilazide or 2,2,6,6-tetramethylpiperidide and the hydrocarbyl group was phenyl or ethyl. In contrast, the use of a dipyridylamide (dpa) based arylzinc complex led to Zn-C/H-BPin metathesis being the major outcome. Independent synthesis and full characterisation of two LnLi[(dpa)ZnPh2] (L = THF,n= 3; L = PMDETA,n= 1) complexes,1and3, respectively, enabled reactivity studies that demonstrated that these species display zincate type reactivity (by comparison to the lower reactivity of the neutral complex (Me-dpa)ZnPh2,4, Me-dpa = 2,2′-dipyridyl-N-methylamine). This included1performing the rapid deprotonation of 4-ethynyltoluene and also phenyl transfer to α,α,α-trifluoroacetophenone in contrast to neutral complex4. Complex1reacted with one equivalent of HBPin to give predominantly PhBPin (ca.90%) and a lithium amidophenylzincate containing a hydride unit, complex7-A, as the major zinc containing product. Complex7-Atransfers hydride to an electrophile preferentially over phenyl, indicating it reacts as a hydridozincate. Attempts to react1with >1 equivalent of HBPin or with catecholborane led to more complex outcomes, which included significant borane and dpaZn substituent scrambling, two examples of which were crystallographically characterised. While this work provides proof of principle for Zn-C/H-BPin exchange as a route to form an amido-zincate containing a hydride, amido-organozincates that undergo more selective Zn-C/H-BPin exchange still are required.
Tunable System for Electrochemical Reduction of Ketones and Phthalimides
Chen, Gong,Qiao, Tianjiao,Wang, Yaxin,Zhang, Jian,Zhao, Jianyou
supporting information, p. 3297 - 3302 (2021/10/14)
Herein, we report an efficient, tunable system for electrochemical reduction of ketones and phthalimides at room temperature without the need for stoichiometric external reductants. By utilizing NaN3 as the electrolyte and graphite felt as both the cathode and the anode, we were able to selectively reduce the carbonyl groups of the substrates to alcohols, pinacols, or methylene groups by judiciously choosing the solvent and an acidic additive. The reaction conditions were compatible with a diverse array of functional groups, and phthalimides could undergo one-pot reductive cyclization to afford products with indolizidine scaffolds. Mechanistic studies showed that the reactions involved electron, proton, and hydrogen atom transfers. Importantly, an N3/HN3 cycle operated as a hydrogen atom shuttle, which was critical for reduction of the carbonyl groups to methylene groups.
Visible Light Induced Reduction and Pinacol Coupling of Aldehydes and Ketones Catalyzed by Core/Shell Quantum Dots
Xi, Zi-Wei,Yang, Lei,Wang, Dan-Yan,Feng, Chuan-Wei,Qin, Yufeng,Shen, Yong-Miao,Pu, Chaodan,Peng, Xiaogang
, p. 2474 - 2488 (2021/02/05)
We present an efficient and versatile visible light-driven methodology to transform aryl aldehydes and ketones chemoselectively either to alcohols or to pinacol products with CdSe/CdS core/shell quantum dots as photocatalysts. Thiophenols were used as proton and hydrogen atom donors and as hole traps for the excited quantum dots (QDs) in these reactions. The two products can be switched from one to the other simply by changing the amount of thiophenol in the reaction system. The core/shell QD catalysts are highly efficient with a turn over number (TON) larger than 4 × 104 and 4 × 105 for the reduction to alcohol and pinacol formation, respectively, and are very stable so that they can be recycled for at least 10 times in the reactions without significant loss of catalytic activity. The additional advantages of this method include good functional group tolerance, mild reaction conditions, the allowance of selectively reducing aldehydes in the presence of ketones, and easiness for large scale reactions. Reaction mechanisms were studied by quenching experiments and a radical capture experiment, and the reasons for the switchover of the reaction pathways upon the change of reaction conditions are provided.
Photo-induced phosphorus radical involved semipinacol rearrangement reaction: Highly synthesis of γ-oxo-phosphonates
Wang, Chunhai,Huang, Xiaoling,Liu, Xueting,Gao, Suqian,Zhao, Bin,Yang, Shangdong
supporting information, p. 677 - 680 (2019/08/27)
Hydroxyphosphoric acids display the unique biological activities, and they have some attractive prospects as clinical drug moleculars. Herein, a new approach for the synthesis of γ-oxo-phosphonates (the precursor of hydroxyphosphoric acid) has been established through the semipinacol rearrangement tactic involved the photo-induced phosphorus radical process. Most important, this transformation is avoid of the external oxidants, and occurs very well under the sunlight irradiation, meanwhile the γ-oxo-phosphonate was easily derivatized to obtain γ-hydroxyphosphoric acid, thus highlights the synthesis value of this method.
A facile and highly efficient transfer hydrogenation of ketones and aldehydes catalyzed by palladium nanoparticles supported on mesoporous graphitic carbon nitride
Ni?anc?, Bilal,Da?alan, Ziya
, p. 14 - 19 (2019/11/14)
A novel transfer hydrogenation methodology for the reduction of ketones (14 examples) and benzaldehyde derivatives (12 examples) to the corresponding alcohols using Pd nanoparticles supported on mesoporous graphitic carbon nitride (mpg-C3N4/Pd) as a reusable catalyst and ammonia borane as a safe hydrogen source in an aqueous solution MeOH/H2O (v/v = 1/1) is described. The catalytic hydrogenation reactions were conducted in a commercially available high-pressure glass tube at room temperature, and the corresponding alcohols were obtained in high yields in 2–5 min. Moreover, the presented transfer hydrogenation protocol shows partial halogen selectivity with bromo-, fluoro-, and chloro-substituted carbonyl analogs. In addition, the present catalyst can be reused up to five times without losing its efficiency, and scaling-up the reaction enables α-methylbenzyl alcohol to be produced in 90% isolated yield.
