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.).
AIBN initiated functionalization of the benzylic sp3 C[sbnd]H and C[sbnd]C bonds in the presence of dioxygen
Hu, Yingying,Shao, Yu,Zhang, Shuwei,Yuan, Yuan,Sun, Zheng,Yuan, Yu,Jia, Xiaodong
supporting information, (2021/02/01)
A sp3 C[sbnd]H bond functionalization and C[sbnd]C bond cleavage were realized by AIBN/O2 catalyst system, providing a series of benzophenones under mild reaction conditions. The mechanistic study shows that a peroxide intermediate is involved in this transformation, and in the case of diphenylmethanes, the sp3 C[sbnd]C bond is cleaved through the peroxide rearrangement, which might provides a new way to cleave relatively strong C[sbnd]C bond and be applied to more general C[sbnd]C bond activation.
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.
Nano NiFe2O4 supported phenanthroline Cu(II) complex as a retrievable catalyst for selective and environmentally friendly oxidation of benzylic alcohols
Mehrjoyan, Forouzan,Afshari, Mozhgan
, (2021/03/24)
A new magnetically recoverable catalyst consisting of phenanthroline Cu(II) complex supported on nickel ferrite nanoparticles was prepared. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission and scanning electron microscopes, thermogravimetry, energy dispersive X-ray spectroscopy, vibrating sample magnetometry and inductively coupled plasma. Supported copper complex used for solvent free oxidation of 1- phenyl ethanol as a model. Influence of the reaction parameters (kind of oxidant, amount of the catalyst, reaction time, solvent and reaction temperature) were studied. Because of the immobilized complex has been shown to be an efficient heterogeneous catalyst for the selective oxidation of 1-phenyl ethanol to acetophenone (94% yield) by hydrogen peroxide so this green approach extended to other benzylic alcohols. The catalyst had been reused 10 times with no significant loss of catalytic activity. SEM, EDX, XRD, and ICP analysis of reused catalyst indicated that the catalyst was stable after the reaction.
