936-59-4Relevant articles and documents
Enantioselective Morita-Baylis-Hillman reaction catalyzed by a chiral phosphine oxide
Kotani, Shunsuke,Ito, Masaya,Nozaki, Hirono,Sugiura, Masaharu,Ogasawara, Masamichi,Nakajima, Makoto
, p. 6430 - 6433 (2013)
An application of a hypervalent silicon complex, generated from a chiral phosphine oxide catalyst and silicon tetrachloride, to the enantioselective organocatalytic Morita-Baylis-Hillman reaction is described. A chloride anion liberated from the hypervalent silicon complex smoothly generated a γ-chloro silyl enol ether that subsequently reacted with an aldehyde to afford the Baylis-Hillman adducts in good yields and with good enantioselectivities.
I2-Promoted Intramolecular Oxidative Cyclization of Butenyl Anilines: A Facile Route to Benzo[b]azepines
An, Zhenyu,Ren, Yi,Liu, Yafeng,Yan, Rulong
supporting information, p. 2614 - 2617 (2021/08/06)
A metal-free approach for the synthesis of seven-membered N-heterocycles has been developed by the I2-promoted intramolecular cross-coupling/annulation of butenyl anilines. This cyclization reaction involves C?H activation and C?C bond formation and exhibits good functional group tolerance. A series of benzo[b]azepine derivatives are obtained in moderate to good yields.
V2O5@TiO2 Catalyzed Green and Selective Oxidation of Alcohols, Alkylbenzenes and Styrenes to Carbonyls
Upadhyay, Rahul,Kumar, Shashi,Maurya, Sushil K.
, p. 3594 - 3600 (2021/07/02)
The versatile application of different functional groups such as alcohols (1° and 2°), alkyl arenes, and (aryl)olefins to construct carbon-oxygen bond via oxidation is an area of intense research. Here, we report a reusable heterogeneous V2O5@TiO2 catalyzed selective oxidation of various functionalities utilizing different mild and eco-compatible oxidants under greener reaction conditions. The method was successfully applied for the alcohol oxidation, oxidative scission of styrenes, and benzylic C?H oxidation to their corresponding aldehydes and ketones. The utilization of mild and eco-friendly oxidizing reagents such as K2S2O8, H2O2 (30 % aq.), TBHP (70 % aq.), broad substrate scope, gram-scale synthesis, and catalyst recyclability are notable features of the developed protocol.
Iron-Catalyzed Wacker-type Oxidation of Olefins at Room Temperature with 1,3-Diketones or Neocuproine as Ligands**
Kataeva, Olga,Kn?lker, Hans-Joachim,Linke, Philipp,Puls, Florian
supporting information, p. 14083 - 14090 (2021/05/24)
Herein, we describe a convenient and general method for the oxidation of olefins to ketones using either tris(dibenzoylmethanato)iron(III) [Fe(dbm)3] or a combination of iron(II) chloride and neocuproine (2,9-dimethyl-1,10-phenanthroline) as catalysts and phenylsilane (PhSiH3) as additive. All reactions proceed efficiently at room temperature using air as sole oxidant. This transformation has been applied to a variety of substrates, is operationally simple, proceeds under mild reaction conditions, and shows a high functional-group tolerance. The ketones are formed smoothly in up to 97 % yield and with 100 % regioselectivity, while the corresponding alcohols were observed as by-products. Labeling experiments showed that an incorporated hydrogen atom originates from the phenylsilane. The oxygen atom of the ketone as well as of the alcohol derives from the ambient atmosphere.
Catalytic Aerobic Oxidation of Alkenes with Ferric Boroperoxo Porphyrin Complex; Reduction of Oxygen by Iron Porphyrin
Kimura, Kento,Kurahashi, Takuya,Matsubara, Seijiro,Murano, Shunpei
supporting information, p. 2493 - 2497 (2021/12/29)
We herein describe the development of a mild and selective catalytic aerobic oxidation process of olefins. This catalytic aerobic oxidation reaction was designed based on experimental and spectroscopic evidence assessing the reduction of atmospheric oxygen using a ferric porphyrin complex and pinacolborane to form a ferric boroperoxo porphyrin complex as an oxidizing species. The ferric boroperoxo porphyrin complex can be utilized as an in-situ generated intermediate in the catalytic aerobic oxidation of alkenes under ambient conditions to form oxidation products that differ from those obtained using previously reported ferric porphyrin catalysis. Moreover, the mild reaction conditions allow chemoselective oxidation to be achieved.
Synthesis and Evaluation of 2-Azetidinone and 1H-Pyrrole-2,5-dione Derivatives as Cholesterol Absorption Inhibitors for Reducing Inflammation Response and Oxidative Stress
Xia, Yineng,Zhu, Lijuan,Yuan, Xinrui,Wang, Yubin
, (2019/01/10)
Excess lipid accumulation can initiate the development and progression of atherosclerotic lesions, thus eventually leading to cardiovascular disease. Lipid-lowering medication therapy is one of the cornerstones of cardiovascular disease therapy. On the basis of the cholesterol absorption inhibitor ezetimibe, we successfully synthesized seven 2-azetidinone derivatives and eighteen 1H-pyrrole-2,5-dione derivatives. Most of the new compounds significantly inhibited cholesterol uptake in vitro. In addition, one of the most active inhibitors, 3-(4-fluorophenyl)-1-[(3S)-3-hydroxy-3-(4-hydroxyphenyl)propyl]-4-(4-hydroxyphenyl)-1H-pyrrole-2,5-dione (14q), showed no cytotoxicity in L02 and HEK293T cell lines. Further evaluation indicated that 14q inhibited considerably the amount of TNF-α, ROS, MDA, and LDH in vitro. Therefore, 14q might be a novel cholesterol absorption inhibitor.
Manganese-Catalyzed Electrochemical Deconstructive Chlorination of Cycloalkanols via Alkoxy Radicals
Allen, Benjamin D. W.,Hareram, Mishra Deepak,Seastram, Alex C.,McBride, Tom,Wirth, Thomas,Browne, Duncan L.,Morrill, Louis C.
supporting information, p. 9241 - 9246 (2019/11/19)
A manganese-catalyzed electrochemical deconstructive chlorination of cycloalkanols has been developed. This electrochemical method provides access to alkoxy radicals from alcohols and exhibits a broad substrate scope, with various cyclopropanols and cyclobutanols converted into synthetically useful β- and γ-chlorinated ketones (40 examples). Furthermore, the combination of recirculating flow electrochemistry and continuous inline purification was employed to access products on a gram scale.
Oxidation of secondary alcohols using solid-supported hypervalent iodine catalysts
Ballaschk, Frederic,Kirsch, Stefan F.
supporting information, p. 5896 - 5903 (2019/11/11)
It is shown how secondary alcohols are oxidized to provide the corresponding ketones by use of Oxone and solid-supported hypervalent iodine catalysts. Under experimentally simple conditions with acetonitrile at elevated temperatures, excellent conversions were achieved with low catalyst loadings (0.2-5 mol%) when employing the conjugates 5 and 6 derived from IBX and IBS. The catalysts are broadly applicable to a range of alcohol substrates. Of primary importance with respect to sustainability issues, the metal-free catalysts are easily removed from the reaction mixture through filtration, and they can be re-used in oxidation processes for multiple times, without loss of catalytic activity.
A Novel Phenylchromane Derivative Increases the Rate of Glucose Uptake in L6 Myotubes and Augments Insulin Secretion from Pancreatic Beta-Cells by Activating AMPK
Rozentul, Naomi,Avrahami, Yosef,Shubely, Moran,Levy, Laura,Munder, Anna,Cohen, Guy,Cerasi, Erol,Sasson, Shlomo,Gruzman, Arie
, p. 2873 - 2890 (2017/10/13)
Purpose: A series of novel polycyclic aromatic compounds that augment the rate of glucose uptake in L6 myotubes and increase glucose-stimulated insulin secretion from beta-cells were synthesized. Designing these molecules, we have aimed at the two main pathogenic mechanisms of T2D, deficient insulin secretion and diminished glucose clearance. The ultimate purpose of this work was to create a novel antidiabetic drug candidate with bi-functional mode of action. Methods: All presented compounds were synthesized, and characterized in house. INS-1E cells and L6 myoblasts were used for the experiments. The rate of glucose uptake, mechanism of action, level of insulin secretion and the druggability of the lead compound were studied. Results: The lead compound (6-(1,3-dithiepan-2-yl)-2-phenylchromane), dose- and time-dependently at the low μM range increased the rate of glucose uptake in L6 myotubes and insulin secretion in INS-1E cells. The compound exerted its effects through the activation of the LKB1 (Liver Kinase B1)-AMPK pathway. In vitro metabolic parameters of this lead compound exhibited good druggability. Conclusions: We anticipate that bi-functionality (increased rate of glucose uptake and augmented insulin secretion) will allow the lead compound to be a starting point for the development of a novel class of antidiabetic drugs.
Wacker-Type Oxidation Using an Iron Catalyst and Ambient Air: Application to Late-Stage Oxidation of Complex Molecules
Liu, Binbin,Jin, Fengli,Wang, Tianjiao,Yuan, Xiaorong,Han, Wei
supporting information, p. 12712 - 12717 (2017/09/11)
A practical and general iron-catalyzed Wacker-type oxidation of olefins to ketones is presented, and it uses ambient air as the sole oxidant. The mild oxidation conditions enable exceptional functional-group tolerance, which has not been demonstrated for any other Wacker-type reaction to date. The inexpensive and nontoxic reagents [iron(II) chloride, polymethylhydrosiloxane, and air] can, therefore, also be employed to oxidize complex natural-product-derived and polyfunctionalized molecules.
