4702-34-5Relevant academic research and scientific papers
Cu(I)-Based Metal-Organic Frameworks as Efficient and Recyclable Heterogeneous Catalysts for Aqueous-Medium C-H Oxidation
Gao, Kuan,Huang, Chao,Yang, Yisen,Li, Hong,Wu, Jie,Hou, Hongwei
, p. 976 - 982 (2019)
The enantioselective transformation of ubiquitous C-H bonds into valuable C-O bonds offers an efficient synthetic approach to construct carbonyl functionalized molecules. However, the grand obstacles in the reaction are the selectivity issues and side reactions under the harsh reaction conditions. In order to overcome the limits, two Cu(I)-based MOFs {(NEt4)0.5[Cu3(TTPB)0.75(CN)0.5(H2O)]·H2O}n (1) and {[Cu2(TTPB)0.5]·DMF·2H2O}n (2) were synthesized (H4TTPB = 5,5′-(4′,5′-bis(4-(1H-tetrazol-5-yl)phenyl)-[1,1′:2′,1′′-terphenyl]-4,4′′-diyl) bis(1H-tetrazole)) under hydrothermal conditions with (triethylamine (TEA) and ethyldiisopropylamine (DIPEA) as structure-directing agents, respectively. Of these, 1 shows an anionic three-dimensional (3D) framework composed of two kinds of cagelike micropores with 7 × 17 ? and 10 × 17 ?, respectively. In comparison, 2 exhibits a 3D framework with open channels (14 × 8 ?). The stability studies showed that the crystallinity of 1 and 2 could remain in a series of organic solvents (ethanol, N,N-dimethylformamide, chloroform, dioxane, toluene) and acid and alkali aqueous solutions (pH = 1-13) at room temperature for 48 h. 1 and 2 with coordinatively unsaturated Cu(I) sites were applied as heterogeneous catalysts for the oxidation of arylacycloalkanes in aqueous medium and exhibited excellent catalytic activities, selectivities, and recyclabilities. Moreover, free-radical reaction mechanism and reversible valence-tautomeric conversions of central copper were confirmed during the process by control experiment.
9.4 T and 7.05 T magnetic fields accelerate a radical oxidation reaction with a hypervalent (tert-butylperoxy)iodane
Iba, Kaori,Fukuyoshi, Shu-Ichi,Kusumi, Takenori
, p. 716 - 717 (2004)
Strong magnetic fields produced by NMR spectrometers (300 and 400 MHz) accelerate the radical oxidation of isochroman with a hypervalent (tert-butylperoxy)iodane.
Di-tert-butyl Peroxide (DTBP)-Mediated Oxidative Cross- Coupling of Isochroman and Indole Derivatives
Jin, Likun,Feng, Jie,Lu, Guoping,Cai, Chun
, p. 2105 - 2110 (2015)
A metal-free C-C bond formation method via the oxidative cross-coupling reaction of isochroman and indole derivatives was established. Various α-fuctionalized cyclic ethers were achieved in satisfactory yields using di-tert-butyl peroxide (DTBP) as the oxidant. This method is also a potentially efficient strategy for the construction of cyclic ether-containing targets.
Visible-light-catalyzed direct benzylic C(sp3)-H amination reaction by cross-dehydrogenative coupling
Pandey, Ganesh,Laha, Ramkrishna
, p. 14875 - 14879 (2015)
A conceptually new and synthetically valuable cross-dehydrogenative benzylic C(sp3)-H amination reaction is reported by visible-light photoredox catalysis. This protocol employs DCA (9,10-dicyanoanthracene) as a visible-light-absorbing photoredox catalyst and an amide as the nitrogen source without the need of either a transition metal or an external oxidant. Amination: A metal and external oxidant-free benzylic amination driven by visible light in the presence of a sensitizer is reported (see picture). This approach is an innovative addition to the established procedures. The substrate scope and mechanistic experiments provide a good insight into the general reaction.
Synthesis and biological evaluation of 1-amino isochromans from 2-bromoethyl benzaldehyde and amines in acid medium
Fatima, Narjis,Reddy, B.V. Subba,Gowravaram, Sabitha,Yadav,Kadari, Sudhakar,Putta, Chandra Shekar
, p. 196 - 201 (2018)
We have developed a facile and efficient synthetic route to substituted isochromans for the first time by reacting 2-(2-bromoethyl)benzaldehyde with a variety of aryl, heteroaryl amines in AcOH. The reaction is catalyst/additive free and takes place at reflux conditions with short reaction time to furnish products in good to excellent yields. All the compounds have been characterized by spectral techniques such as IR, 1H NMR and Mass etc. Synthesized compounds were evaluated for antimicrobial activity against specific bacterial like 1) Staphylococcus strains aureus 2) Bacillus subtilis 3) Escherichia coli 4) Pseudomonas aeruginosa. Compounds 3e, 3n, 3 m, 3 l, 3 k, 3j and 3b showed most potent in vitro activity against bacterial strains.
Microwave-Assisted Oxidation of Side Chain Arenes by Magtrieve
Lukasiewicz, Marcin,Bogdal, Dariusz,Pielichowski, Jan
, p. 1269 - 1272 (2003)
A commercial tetravalent chromium dioxide (Magtrieve) as a magnetically retrievable oxidant is shown to be a very useful compound for microwave-assisted and conventional transformation of aromatic and alkyl aromatic molecules into the corresponding aryl ketones, quinones or lactones.
HCl-Catalyzed Aerobic Oxidation of Alkylarenes to Carbonyls
Niu, Kaikai,Shi, Xiaodi,Ding, Ling,Liu, Yuxiu,Song, Hongjian,Wang, Qingmin
, (2021/12/13)
The construction of C?O bonds through C?H bond functionalization remains fundamentally challenging. Here, a practical chlorine radical-mediated aerobic oxidation of alkylarenes to carbonyls was developed. This protocol employed commercially available HCl as a hydrogen atom transfer (HAT) reagent and air as a sustainable oxidant. In addition, this process exhibited excellent functional group tolerance and a broad substrate scope without the requirement for external metal and oxidants. The mechanistic hypothesis was supported by radical trapping, 18O labeling, and control experiments.
Two transition-metal-modified Nb/W mixed-addendum polyoxometalates for visible-light-mediated aerobic benzylic C–H oxidations
Chen, Xuenian,Gao, Fan,Li, Na,Li, Shujun,Ma, Yubin,Xiao, Wanru,Yu, Bing
supporting information, (2022/03/27)
The visible-light-induced selective oxidation of ubiquitous C–H bonds into valuable C=O bonds under aerobic conditions is one of the most attractive approaches for the construction of carbonyl-containing molecules. In this work, two transition metal-containing Nb/W mixed-addendum POMs dimers with the formula of K2Na2H5[(Fe(H2O)4)3(P2W15Nb3O62)2]?24H2O (POM[Fe]) and K2Na3H4[(Cr(H2O)4)3(P2W15Nb3O62)2]?32H2O (POM[Cr]) have been synthesized and characterized by various analytical and spectral techniques. POM[Fe] was proved to be an efficient photocatalyst for benzylic C–H oxidation under visible light and using oxygen as an oxidant to produce the corresponding carbonyl complex in good yields. A plausible mechanism involving superoxide radical was proposed for the catalytic reaction. POM[Fe] showed good reusability in the recycling experiments. IR spectroscopy and XRD analysis indicate that POM[Fe] can retain its integrity after catalysis.
Selective Aerobic Oxidation of Csp3-H Bonds Catalyzed by Yeast-Derived Nitrogen, Phosphorus, and Oxygen Codoped Carbon Materials
Ju, Zhao-Yang,Song, Li-Na,Chong, Ming-Ben,Cheng, Dang-Guo,Hou, Yang,Zhang, Xi-Ming,Zhang, Qing-Hua,Ren, Lan-Hui
supporting information, p. 3978 - 3988 (2022/03/16)
Nitrogen, phosphorus, and oxygen codoped carbon catalysts were successfully synthesized using dried yeast powder as a pyrolysis precursor. The yeast-derived heteroatom-doped carbon (yeast@C) catalysts exhibited outstanding performance in the oxidation of Csp3-H bonds to ketones and esters, giving excellent product yields (of up to 98% yield) without organic solvents at low O2pressure (0.1 MPa). The catalytic oxidation protocol exhibited a broad range of substrates (38 examples) with good functional group tolerance, excellent regioselectivity, and synthetic utility. The yeast-derived heteroatom-doped carbon catalysts showed good reusability and stability after recycling six times without any significant loss of activity. Experimental results and DFT calculations proved the important role of N-oxide (N+-O-) on the surface of yeast@C and a reasonable carbon radical mechanism.
Stepwise benzylic oxygenation via uranyl-photocatalysis
Hu, Deqing,Jiang, Xuefeng
supporting information, p. 124 - 129 (2022/01/19)
Stepwise oxygenation at the benzylic position (1°, 2°, 3°) of aromatic molecules was comprehensively established under ambient conditions via uranyl photocatalysis to produce carboxylic acids, ketones, and alcohols, respectively. The accuracy of the stepwise oxygenation was ensured by the tunability of catalytic activity in uranyl photocatalysis, which was adjusted by solvents and additives demonstrated through Stern–Volmer analysis. Hydrogen atom transfer between the benzylic position and the uranyl catalyst facilitated oxygenation, further confirmed by kinetic studies. Considerably improved efficiency of flow operation demonstrated the potential for industrial synthetic application.
