6563-13-9Relevant academic research and scientific papers
Energetics of 6-methoxyquinoline and 6-methoxyquinoline N-oxide: The dissociation enthalpy of the (N-O) bond
Da Silva, Maria D.M.C. Ribeiro,Santos, Luis M.N.B.F.,Silva, Ana L.R.,Fernandes, Oscar,Acree Jr.
, p. 1093 - 1100 (2003)
The standard (p° = 0.1MPa) molar enthalpies of formation, at T = 298.15K, were determined using static-bomb calorimetry for crystalline 6-methoxyquinoline N-oxide (6MeOQUINO), as -(85.6 ± 3.7) kJ·mol-1 and liquid 6-methoxyquinoline (6MeOQUI), -(25.8 ± 2.2)kJ·mol-1. The standard molar enthalpies of sublimation/vaporization, at T = 298.15K, were measured by microcalorimetry and from the enthalpies of formation of the gaseous compounds, the dissociation enthalpy Dm0 of the (N+-O-) dative covalent bond was derived, as (269.2 ± 5.0)kJ·mol-1.
Electrochemical-Oxidation-Promoted Direct N-ortho-Selective Difluoromethylation of Heterocyclic N-Oxides
Zhang, Dong,Cai, Jinlin,Du, Jinze,Wang, Qingdong,Yang, Jinming,Geng, Rongqing,Fang, Zheng,Guo, Kai
supporting information, p. 1434 - 1438 (2022/03/01)
An efficient and green electrochemical N-ortho-selective difluoromethylation method of various quinoline and isoquinoline N-oxides has been developed. In this method, sodium difluoromethanesulfinate (HCF2SO2Na) was used as the source of the difluoromethyl moiety, and various N-ortho-selective difluoromethylation quinoline and isoquinoline N-oxides were obtained in good to excellent yields under a constant current. In addition, the reaction was easy to scale up and maintained a good yield. Preliminary mechanism studies suggested that the reaction undergoes a free-radical addition and hydrogen elimination pathway.
Quinoline Ligands Improve the Classic Direct C?H Functionalisation/Intramolecular Cyclisation of Diaryl Ethers to Dibenzofurans
Mackey, Katrina,Jones, David J.,Pardo, Leticia M.,McGlacken, Gerard P.
supporting information, p. 495 - 498 (2021/01/12)
The C?H functionalisation approach to the synthesis of dibenzofurans is hampered by a number of problems. Herein we describe the evolution of a cheap, bench stable quinoline ligand, which obviates most of the current limitations and allows for a high yielding synthesis of a range of valuable dibenzofurans. Dibenzofurans are important motifs in natural products and compounds with wide biological activity.
Waste-minimized synthesis of C2 functionalized quinolines exploiting iron-catalysed C-H activation
Ferlin, Francesco,Zangarelli, Agnese,Lilli, Simone,Santoro, Stefano,Vaccaro, Luigi
supporting information, p. 490 - 495 (2021/01/28)
Herein we present an efficient and regioselective iron-catalyzed methodology for the external oxidant-free functionalization of quinoline-N-oxides. The protocol, based on the use of inexpensive and easily accessible FeSO4, showed broad applicability to a wide range of substrates. An additional green feature of this synthetic methodology is H2O being the only by-product. Experimental and computational investigations provide support to a mechanism based on a facile C-H activation event. The green efficiency of the process has also been carefully assessed using: (i) metrics related to the synthetic process (AE, Yield, 1/SF, MRP and RME); (ii) safety/hazard metrics (SHZI and SHI); and (iii) metrics related to the metal used as the catalyst (Abundance, OEL and ADP). In addition to the many advantages of this protocol related to the green iron catalyst used and the safety/hazard features of the process, an E-factor value of ca. 0.92 (84 to >99% reduction compared to known protocols) evidently confirms the sustainable efficiency of the procedure presented. Practical utility has also been demonstrated by performing the reaction efficiently on a multi-gram scale. This journal is
Deoxygenative C2-heteroarylation of quinoline N-oxides: Facile access to α-Triazolylquinolines
Sontakke, Geetanjali S.,Shukla, Rahul K.,Volla, Chandra M. R.
supporting information, p. 485 - 493 (2021/03/22)
A metal-and additive-free, highly efficient, step-economical deoxygenative C2-heteroarylation of quinolines and isoquinolines was achieved from readily available N-oxides and N-sulfonyl-1,2,3-Triazoles. A variety of α-Triazolylquinoline derivatives were synthesized with good regioselectivity and in excellent yields under mild reaction conditions. Further, a gram-scale and one-pot synthesis illustrated the efficacy and simplicity of the developed protocol. The current transformation was also found to be compatible for the late-stage modification of natural products.
Metal-free C8-H functionalization of quinolineN-oxides with ynamides
Hu, Weican,Zhang, Feiyang,Chen, Chen,Qi, Tianhang,Shen, Yanlong,Qian, Guoying,Rong, Zhouting
supporting information, p. 6995 - 6998 (2021/07/21)
The metal-free C8-H functionalization of quinolineN-oxides with ynamides is unveiled for the first time by the intramolecular Friedel-Crafts-type reaction of quinolyl enolonium intermediates generated from Br?nsted acid-catalyzed addition of quinolineN-ox
Copper/manganese oxide catalyzed regioselective amination of quinoline N-oxides: An example of synergistic cooperative catalysis
Sahoo, Tapan,Thakur, Dinesh,Panda, Asit Baran,Ghosh, Subhash Chandra
supporting information, (2021/09/29)
An atom economical and efficient protocol for C-2 amination of quinoline N-oxides using our synthesized recyclable heterogeneous Cu–MnO catalyst has been reported here. Direct C[sbnd]H aminations of heterocyclic N-oxides with secondary amine were carried out under base, and ligand-free conditions in good to excellent yields. The major advantage is that air is used as a sole oxidant and our catalyst is recycled several times.
Deoxygenative Amination of Azine-N-oxides with Acyl Azides via [3 + 2] Cycloaddition
Ghosh, Prithwish,Han, Sang Hoon,Han, Sangil,Kim, Dongeun,Kim, In Su,Kim, Saegun,Kwon, Na Yeon,Mishra, Neeraj Kumar
, p. 2476 - 2485 (2020/03/13)
A transition-metal-free deoxygenative C-H amination reaction of azine-N-oxides with acyl azides is described. The initial formation of an isocyanate from the starting acyl azide via a Curtius rearrangement can trigger a [3 + 2] dipolar cycloaddition of polar N-oxide fragments to generate the aminated azine derivative. The applicability of this method is highlighted by the late-stage and sequential amination reactions of complex bioactive compounds, including quinidine and fasudil. Moreover, the direct transformation of aminated azines into various bioactive N-heterocycles illustrates the significance of this newly developed protocol.
Developing Inhibitors of the p47phox-p22phox Protein-Protein Interaction by Fragment-Based Drug Discovery
Solbak, Sara Marie ?ie,Zang, Jie,Narayanan, Dilip,H?j, Lars Jakobsen,Bucciarelli, Saskia,Softley, Charlotte,Meier, Sebastian,Langkilde, Annette Eva,Gotfredsen, Charlotte Held,Sattler, Michael,Bach, Anders
, p. 1156 - 1177 (2020/03/10)
Nicotinamide adenine dinucleotide phosphate oxidase isoform 2 is an enzyme complex, which generates reactive oxygen species and contributes to oxidative stress. The p47phox-p22phox interaction is critical for the activation of the catalytical NOX2 domain, and p47phox is a potential target for therapeutic intervention. By screening 2500 fragments using fluorescence polarization and a thermal shift assay and validation by surface plasmon resonance, we found eight hits toward the tandem SH3 domain of p47phox (p47phoxSH3A-B) with KD values of 400-600 μM. Structural studies revealed that fragments 1 and 2 bound two separate binding sites in the elongated conformation of p47phoxSH3A-B and these competed with p22phox for binding to p47phoxSH3A-B. Chemical optimization led to a dimeric compound with the ability to potently inhibit the p47phoxSH3A-B-p22phox interaction (Ki of 20 μM). Thereby, we reveal a new way of targeting p47phox and present the first report of drug-like molecules with the ability to bind p47phox and inhibit its interaction with p22phox.
Co(III)-Catalyzed C-H Amidation of Nitrogen-Containing Heterocycles with Dioxazolones under Mild Conditions
Dhiman, Ankit Kumar,Thakur, Ankita,Kumar, Inder,Kumar, Rakesh,Sharma, Upendra
, p. 9244 - 9254 (2020/08/14)
A cobalt(III)-catalyzed C-8 selective C-H amidation of quinoline N-oxide using dioxazolone as an amidating reagent under mild conditions is disclosed. The reaction proceeds efficiently with excellent functional group compatibility. The utility of the current method is demonstrated by gram scale synthesis of C-8 amide quinoline N-oxide and by converting this amidated product into functionalized quinolines. Furthermore, the developed catalytic method is also applicable for C-7 amidation of N-pyrimidylindolines and ortho-amidation of benzamides.
