90-96-0Relevant articles and documents
Chemical capture of an unprecedented oxatetramethyleneethane radical cation with a through-space electronic coupling
Ikeda, Hiroshi,Tanaka, Futoshi,Kabuto, Chizuko
, p. 2663 - 2667 (2005)
A photoinduced electron-transfer reaction of 2,2-dianisyl-4-isopropylidene- 3,3-dimethylcyclobutanone (5) in acetonitrile containing molecular oxygen or water gave 4,4′-dimethoxybenzophenone (7) and 2,2-dianisyl-4- isopropylidene-5,5-dimethylhydrofuran-3-one (8), demonstrating the chemical capture of an unprecedented oxatetramethyleneethane-type radical cation intermediate (6?+). A density functional theory calculation suggests through-space electronic coupling between the tetramethylallyl and joined dianisylmethyl carbonyl subunits in 6?+.
1,3-Oxathiolanes from the reaction of aromatic and enolized thioketones with monosubstituted oxiranes
Fu, Changchun,Linden, Anthony,Heimgartner, Heinz
, p. 2833 - 2847 (2003)
The reactions of 4,4′-dimethoxythiobenzophenone (1) with (S)-2-methyloxirane ((S)-2) and (R)-2-phenyloxirane ((R)-6) in the presence of a Lewis acid such as BF3·Et2O, ZnCl2, or SiO2 in dry CH2Cl2 led to the corresponding 1:1 adducts, i.e., 1,3-oxathiolanes (S)-3 with Me at C(5), and (S)-7 and (R)-8 with Ph at C(4) and C(5), respectively. A 1:2 adduct, 1,3,6-dioxathiocane (4S,8S)-4 and 1,3-dioxolane (S)-9, respectively, were formed as minor products (Schemes 3 and 5, Tables 1 and 2). Treatment of the 1:1 adduct (S)-3 with (S)-2 and BF3·Et2O gave the 1:2 adduct (4S,8S)-4 (Scheme 4). In the case of the enolized thioketone 1,3-diphenylprop-1-ene-2-thiol (10) with (S)-2 and (R)-6 in the presence of SiO2, the enesulfanyl alcohols (1′Z,2S)-11 and (1′E,2S)-11, and (1′Z,2S)-13, (1′E,2S)-13, (1′Z,1R)-15, and (1′E,1R)-15, respectively, as well as a 1,3-oxathiolane (S)-14 were formed (Schemes 6 and 8). In the presence of HCl, the enesulfanyl alcohols (1′Z,2S)-11, (1′Z,2S)-13, (1′E,2S)-13, (1′Z,1R)-15, and (1′E,1R)-15 cyclize to give the corresponding 1,3-oxathiolanes (S)-12, (S)-14, and (R)-16, respectively (Schemes 7, 9, and 10). The structures of (1′E,2S)-11, (S)-12, and (S)-14 were confirmed by X-ray crystallography (Figs. 1-3). These results show that 1,3-oxathiolanes can be prepared directly via the Lewis acid-catalyzed reactions of oxiranes with non-enolizable thioketones, and also in two steps with enolized thioketones. The nucleophilic attack of the thiocarbonyl or enesulfanyl S-atom at the Lewis acid-complexed oxirane ring proceeds with high regio- and stereoselectivity via an SK2-type mechanism.
Preparation, redox properties, and x-ray structures of electrochromic 11,11,12,12-tetraarylanthraquinodimethane and its bianthraquinodimethane analogue: Drastic geometrical changes upon interconversion with dicationic dyes
Sakano, Yuto,Katoono, Ryo,Fujiwara, Kenshu,Suzuki, Takanori
, p. 1143 - 1145 (2014)
Tetrakis(4-methoxyphenyl)anthraquinodimethane 1(b) with a bent geometry undergoes reversible redox interconversion with twisted dication 1(t) 2+ exhibiting a vivid change in color (electrochromism) accompanied by a drastic structural change. Electrochemical oxidation of bianthraquinodimethane 2(b) with a doubly bent structure to bianthrylidene-type twisted dication 2(t)2+ proceeded smoothly, whereas the reverse conversion was less effective because 2(t)2 generated upon reduction of 2(t)2+ is a long-lived species to undergo side reactions.
Supramolecular amphiphiles based on cyclodextrin and hydrophobic drugs
Sun, Tao,Wang, Qingbing,Bi, Yunke,Chen, Xinli,Liu, Lisha,Ruan, Chunhui,Zhao, Zhifeng,Jiang, Chen
, p. 2644 - 2654 (2017)
Herein we report a novel “supra-prodrug-type” superamphiphile design: via a redox-sensitive self-immolative linker, a hydrophobic drug molecule was labeled with an azobenzene moiety, which was designed to be capped by a hydrophilic cyclodextrin (CD) molec
Tris(pentafluorophenyl)borane-Catalyzed Oxygen Insertion Reaction of α-Diazoesters (α-Diazoamides) with Dimethyl Sulfoxide
Gao, Wen-Xia,Liu, Miao-Chang,Wu, Hua-Yue,Wu, Xiao-Yang,Zhou, Yun-Bing
supporting information, (2022/01/19)
A tris(pentafluorophenyl)borane-catalyzed oxidation reaction of α-diazoesters (α-diazo amides) with dimethyl sulfoxide has been developed. The reaction proceeds under metal free conditions to afford a series α-ketoesters and α-ketoamides. The synthetic utility of this protocol is demonstrated through synthetic transformations and scaled-up synthesis. (Figure presented.).
Organotellurium-catalyzed oxidative deoximation reactions using visible-light as the precise driving energy
Deng, Xin,Qian, Rongrong,Zhou, Hongwei,Yu, Lei
supporting information, p. 1029 - 1032 (2020/10/23)
Irradiated by visible light, the recyclable (PhTe)2-catalyzed oxidative deoximation reaction could occur under mild conditions. In comparison with the thermo reaction, the method employed reduced catalyst loading (1 mol% vs. 2.5 mol%), but afforded elevated product yields with expanded substrate scope. This work demonstrated that for the organotellurium-catalyzed reactions, visible light might be an even more precise driving energy than heating because it could break the Te–Te bond accurately to generate the active free radical catalytic intermediates without damaging the fragile substituents (e.g., heterocycles) of substrates. The use of O2 instead of explosive H2O2 as oxidant affords safer reaction conditions from the large-scale application viewpoint.
PhSe(O)OH/NHPI-catalyzed oxidative deoximation reaction using air as oxidant
Shi, Yaocheng,Wang, Feng,Yang, Chenggen,Yu, Lei
, (2021/09/06)
A novel oxidative deoximation method was developed in this article. Compared with the reported organoselenium-catalyzed oxidative deoximation reaction, this reaction employed N-hydroxyphthalimide (NHPI) as the co-catalyst, so that the oxidative deoximation reaction could utilize air as oxidant in the green DMC solvent under mild reaction conditions. Control experiments and X-ray photoelectron spectroscopy (XPS) analysis results indicated that NHPI was essential for activating the catalytic organoselenium species. It could accelerate the activation of molecular oxygen in air to promote the reaction process. The reaction can avoid metal residues in product and is of potential application values in pharmaceutical industry due to the transition metal-free process.
Synthesis of biaryl ketones and biaryl diketones via carbonylative Suzuki-Miyaura coupling reactions catalyzed by bridged bis(N-heterocyclic carbene)palladium(II) catalysts
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Page/Page column 20; 22-26, (2021/12/23)
This disclosure relates to bridged bis(N-heterocyclic carbene)palladium(II) complexes, methods of preparing the complexes, and methods of using the complexes in Suzuki-Miyaura coupling reactions.
Poly(ethylene glycol) dimethyl ether mediated oxidative scission of aromatic olefins to carbonyl compounds by molecular oxygen
Yu, Tao,Guo, Mingqing,Wen, Simiaomiao,Zhao, Rongrong,Wang, Jinlong,Sun, Yanli,Liu, Qixing,Zhou, Haifeng
, p. 13848 - 13852 (2021/04/22)
A simple, and practical oxidative scission of aromatic olefins to carbonyl compounds using O2as the sole oxidant with poly(ethylene glycol) dimethyl ether as a benign solvent has been developed. A wide range of monosubstituted,gem-disubstituted, 1,2-disubstituted, trisubstituted and tetrasubstituted aromatic olefins was successfully converted into the corresponding aldehydes and ketones in excellent yields even with gram-scale reaction. Some control experiments were also conducted to support a possible reaction pathway.
Method for preparing aldehyde ketone compound through olefin oxidation
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Paragraph 0019, (2021/04/07)
The invention provides a method for preparing an aldehyde ketone compound by olefin oxidation, which relates to an olefin oxidative cracking reaction in which oxygen participates. The method comprises the following specific steps: in the presence of a solvent and an oxidant, carrying out oxidative cracking on an olefin raw material to obtain a corresponding aldehyde ketone product. Compared with the traditional method, the method does not need to add any catalyst or ligand, does not need to use high-pressure oxygen, has the advantages of simple and mild reaction conditions, environment friendliness, low cost, high atom economy and the like, is wide in substrate application range and high in yield, and has a wide application prospect in the aspects of synthesis of aldehyde ketone medical intermediates and chemical raw materials.
