1034854-37-9Relevant academic research and scientific papers
CuO-catalyzed oxidation of aryl acetates with aqueous tert-butyl hydroperoxide for the synthesis of α-ketoesters
Jiang, Jin
, p. 235 - 240 (2019)
A practical method to access α-ketoesters from readily available aryl acetates is developed. In this approach, aqueous tert-butyl hydroperoxide and CuO are employed. No additional solvents are required and it was found that the peroxide side products in the reaction can be decomposed by pyridine.
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.).
Unraveling two pathways for NHPI-mediated electrocatalytic oxidation reaction
Xu, Leitao,Yi, Yangjie,Hu, Sideng,Ye, Jiao,Hu, Aixi
, (2021/11/30)
Two pathways for N-hydroxyphthalimide (NHPI)-mediated electrocatalytic oxidation using phenylacetate derivatives as template substrates were first reported for benzylic C[sbnd]H oxidation to oxygenated and non-oxygenated products. DFT calculation indicates that the hydrogen-atom transfer (HAT) process between phthalimido-N-oxyl (PINO) and substrate is a rate-determined step. Aromatic α-keto esters and 2-((1,3-dioxoisoindolin-2-yl)oxy)-2-aryl acetate obtained by cross-coupling between benzylic radical and PINO can be selectively synthesized through controlling the concentration of PINO radical. This method provides a deep understanding for selective weak C[sbnd]H oxidation using NHPI as redox mediator.
Visible-Light-Induced Catalyst-Free Carboxylation of Acylsilanes with Carbon Dioxide
Fan, Zhengning,Yi, Yaping,Chen, Shenhao,Xi, Chanjuan
supporting information, p. 2303 - 2307 (2021/04/05)
Intermolecular carbon-carbon bond formation between acylsilanes and carbon dioxide (CO2) was achieved by photoirradiation under catalyst-free conditions. In this reaction, siloxycarbenes generated by photoisomerization of the acylsilanes added to the C═O bond of CO2 to give α-ketocarboxylates, which underwent hydrolysis to afford α-ketocarboxylic derivatives in good yields. Control experiments suggest that the generated siloxycarbene is likely to be from the singlet state (S1) of the acylsilane and the addition to CO2 is not in a concerted manner.
Preparation method of alpha-ketoester compound
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Paragraph 0098-0101, (2021/04/21)
The invention discloses a preparation method of an alpha-ketone ester compound. The method specifically comprises the following operation steps: adding raw materials alpha-diazo ester and an organic photocatalyst into a reaction flask, then adding an organic solvent, and reacting for 2-12 hours in air at room temperature under the irradiation of a visible light lamp; after the reaction is monitored by thin-layer chromatography (TLC), stopping the reaction, and extracting a reaction solution by using ethyl acetate; concentrating the extracting solution under reduced pressure to obtain a crude product, and performing column chromatography separation on the crude product to obtain the alpha-diazonium ester compound. According to the preparation method, clean visible light is used as reaction energy, cheap organic dye is used as a photocatalyst, air is used as a green oxidizing agent and an oxygen source, and the preparation method has the advantages of simplicity and convenience in operation, no metal residue and mild reaction conditions.
Copper(I)-catalyzed aerobic oxidation of α-diazoesters
Xu, Changming,Bai, Lei,Wang, Yongchang
, p. 12579 - 12584 (2020/11/09)
A practical Cu-catalyzed oxidation of α-diazoesters to α-ketoesters using molecular oxygen as an oxidant has been developed. Both electron-poor and electron-rich aryl α-diazoesters are suitable substrates and provide the α-ketoesters in good yields. In this oxidative system, α-diazo-β-ketoesters are also compatible as substrates but unexpectedly furnish α-ketoesters via C-C bond cleavage, rather than the vicinal tricarbonyl products.
Anti-Selective Catalytic Asymmetric Nitroaldol Reaction of α-Keto Esters: Intriguing Solvent Effect, Flow Reaction, and Synthesis of Active Pharmaceutical Ingredients
Karasawa, Tomoya,Oriez, Rapha?l,Kumagai, Naoya,Shibasaki, Masakatsu
, p. 12290 - 12295 (2018/09/27)
A rare-earth metal/alkali metal bimetallic catalyst proved particularly effective for enantioselectively coupling nitroalkanes and α-keto esters in an anti-selective manner to afford synthetically versatile, densely functionalized, and optically active α-nitro tertiary alcohols. A chiral diamide ligand captured two distinct metal cations, giving rise to a catalytically competent solid-phase heterobimetallic catalyst by simple mixing via self-assembly. The advantage of the solid-phase asymmetric catalyst was realized by successful application to the enantio- and diastereoselective reaction in a continuous-flow platform. The use of closely related solvents in terms of structures and polarity parameters, THF and its methylated congener 2-Me-THF, had an unexpectedly large solvent effect both on the reaction rate and the stereoselectivity. The nitroaldol products share a privileged unit for active pharmaceutical ingredients, as demonstrated by the streamlined enantioselective synthesis of the marketed antifungal agents efinaconazole and albaconazole.
Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: Controlled oxidation of terminal alkynes to glyoxals
Das, Deb Kumar,Kumar Pampana, V. Kishore,Hwang, Kuo Chu
, p. 7318 - 7326 (2018/10/15)
Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal CC alkynes to α-keto esters and quinoxalines via formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O2 as a sustainable oxidant. The current copper catalysed photoredox method is simple, highly functional group compatible with a broad range of electron rich and electron poor aromatic alkynes as well as aliphatic alcohols (1°, 2° and 3° alcohols), providing an efficient route for the preparation of α-keto esters (43 examples), quinoxaline and naphthoquinone with higher yields than those in the literature reported thermal processes. Furthermore, the synthetic utility of the products has been demonstrated in the synthesis of two biologically active molecules, an E. coli DHPS inhibitor and CFTR activator, using the current photoredox process. In addition, we applied this methodology to the one-pot synthesis of a heterocyclic compound (quinoxaline, an FLT3 inhibitor) by trapping the intermediate phenylglyoxal with O-phenylenediamine. The intermediate phenylglyoxal can also be isolated and further reacted with an internal alkyne to form naphthoquinone. This process can be readily scaled up to the gram scale.
MACROCYCLIC BROAD SPECTRUM ANTIBIOTICS
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Paragraph 00917, (2018/09/12)
Provided herein are antibacterial compounds, wherein the compounds in some embodiments have broad spectrum bioactivity. In various embodiments, the compounds act by inhibition of bacterial type 1 signal peptidase (SpsB), an essential protein in bacteria. Pharmaceutical compositions and methods for treatment using the compounds described herein are also provided.
Iridium-Catalyzed Asymmetric Hydrogenation of Unsaturated Piperazin-2-ones
Wang, Yanzhao,Liu, Yuanyuan,Li, Kun,Yang, Guoqiang,Zhang, Wanbin
supporting information, p. 1933 - 1941 (2017/06/09)
Two different iridium catalyst systems, generated from the ruthenocene-based phosphine-oxazoline ligand tBu-mono-RuPHOX or the diphosphine ligand BINAP, were developed for the asymmetric hydrogenation of 5,6-dihydropyrazin-2(1H)-ones, affording chiral piperazin-2-ones in good yields and with moderate to good ees. Different catalytic behaviors for the hydrogenation of these types of substrate were observed with these two catalyst systems. Our tBu-mono-RuPHOX ligand, which bears a ruthenocene scaffold with planar chirality, was found to be the best ligand for the [Ir(L)(COD)]BArF catalyst system, affording the desired products with up to 94% ee. (Figure presented.).
