2518-42-5Relevant academic research and scientific papers
Studies in Nickel(IV) Chemistry. Part 3. Kinetics of Metal(II) Ion-mediated Acid Decomposition of Tris(dimethylglyoximato)-nickelate(IV) in Aqueous Medium
Neogi, Gautam,Acharya, Sridhara,Panda, Rama Krushna,Ramaswamy, Dorai
, p. 1239 - 1246 (1983)
The kinetics of metal(II) ion-mediated acid decomposition of tris(dimethylglyoximato)nickelate(IV), 2-, with concomitant intramolecular electron transfer to produce and Ni2+(aq) have been studied at 35 deg C and ionic strength 0.57 mol dm-3 in aqueous medium in the range 3.6 IV complex and MII(aq) (M=Cu, Zn, or Ni) present in the medium.While the rate-determining steps in the reactions with CuII are envisaged to involve acid decomposition of the adduct formed in addition to proton-assisted decomposition of the NiIV complex, those in the reactions with ZnII and NiII proceed essentially by routes parallel to the proton-assisted decomposition.U.v.-visible spectral changes in the NiIV-CuII reaction indicate the formation of the 1:1 adduct.
Gas-phase spectroscopy of the unstable acetonitrile N-oxide molecule, CH3CNO
Pasinszki, Tibor,Westwood, Nicholas P.C.
, p. 1244 - 1253 (2001)
The unstable acetonitrile N-oxide molecule, CH3CNO, has been thermolytically generated in very high yield in the gas phase from its stable ring dimer, dimethylfuroxan, and studied by ultraviolet photoelectron spectroscopy, photoionization mass spectroscopy, and mid-infrared spectroscopy. The individual spectroscopies provide a detailed investigation into the vibrational and electronic character of the molecule, and are supported by both conventional ab initio calculations and density functional theory. The ground-state structure is also investigated by theory at the B3-LYP, MPn (n = 2-4), QCISD, and QCISD(T) levels with medium to large basis sets, and illustrates the need for a precise description of electron correlation. Given that both isomerization and dimerization are feasible loss processes for this unstable molecule, the relative stability of CH3CNO with respect to the known cyanate (CH3OCN), isocyanate (CH3NCO), and fulminate (CH3ONC) isomers and the mechanism of the dimerization processes were studied with density functional theory.
Oxidation of: O -dioxime by (diacetoxyiodo)benzene: Green and mild access to furoxans
He, Chunlin,Pang, Siping,Zhang, Qi,Zhang, Xun,Zhao, Cheng
supporting information, p. 1489 - 1493 (2022/01/31)
Furoxan has been widely used in the field of high energy density materials because of its excellent properties such as high density, high standard enthalpy of formation and high nitrogen content. However, its existing synthesis methods are still restricted by the problems of difficult substrate preparation and manual handling of hazardous reagents. Herein, we disclosed a mild oxidation strategy to efficiently obtain furoxan derivatives starting from readily available o-dioxime substrates. This reaction features high functional group tolerance and easy scale-up, and has excellent regioselectivity for specific nonsymmetric o-dioximes. This method greatly reduces the safety risk and simplifies the operation process, and means that diversified furoxan derivatives can be easily accessed, thus paving the way for the wide application of furoxan derivatives. This journal is
Unnatural α-amino ethyl esters from diethyl malonate or ethyl β-bromo-α-hydroxyiminocarboxylate
Coutant, Eloi P.,Hervin, Vincent,Gagnot, Glwadys,Ford, Candice,Baatallah, Racha,Janin, Yves L.
supporting information, p. 2853 - 2860 (2018/11/26)
We have explored here the scope of the age-old diethyl malonate-based accesses to α-amino esters involving Knoevenagel condensations of diethyl malonate on aldehydes, reductions of the resulting alkylidenemalonates, the preparation of the corresponding α-hydroxyimino esters and their final reduction. This synthetic pathway turned out to be general although some unexpected limitations were encountered. The synthetic modifications of some of the intermediates - using Suzuki-Miyaura coupling or cycloadditions - before undertaking the oximation step - provided accesses to further α-amino esters. Moreover, other pathways to α-hydroxyimino esters were explored including an attempt to improve the cycloadditions between ethyl β-bromo-α-hydroxyiminocarboxylate and various alkylfuranes.
Synthesis of functionalized 2-isoxazolines as three-dimensional fragments for fragment-based drug discovery
Tran, Ngoc Chau,Dhondt, Heleen,Flipo, Marion,Deprez, Benoit,Willand, Nicolas
supporting information, p. 4119 - 4123 (2015/08/03)
Abstract The design of new sp3 and spiro-enriched fragments has been achieved from 1,3-dipolar cycloaddition between alkenes and chloro-oximes. The selection of reagents was performed to afford a panel of 2-isoxazoline-containing fragments that show desirable three dimensional (3D) characteristics to allow the probing of biologically-relevant chemical space. Principal moments of inertia (PMI) were calculated to evaluate the 3D diversity. The resulting 3D fragments with suitable physicochemical properties, especially a good solubility, will be used to improve the hit rate of our fragment-based screening.
Flash vacuum pyrolysis of 1,2,5-oxadiazole 2-oxides and 1,2,3-triazole 1-oxides
Mitchell, William R.,Paton, R. Michael
experimental part, p. 34 - 54 (2011/02/21)
The flash vacuum pyrolysis (FVP, 450-600 °C/10-3 mmHg) of 3,4-diaryl- and 3,4-dialkyl-1,2,5-oxadiazole 2-oxides (furoxans) has been investigated. In all cases the 1,2,5-oxadiazole ring cleaved cleanly at O(1)-N(2) and C(3)-C(4) to afford two nitrile oxide fragments, which were trapped in high yield (75-97%) as their isoxazoline cycloadducts by reaction with alk-1-enes. At higher temperatures (700-800 °C) isocyanates were formed as by-products. The dimerisation of acetonitrile oxide to dimethylfuroxan was followed by 1H NMR spectroscopy, and the rate constant for the 2 nd order reaction determined. The furoxans were converted into isocyanates in good yield (61-95%) by FVP, followed by sulfur dioxide-mediated isomerisation of the resulting nitrile oxides. 2,4,5-Trisubstituted-1,2,3- triazole 1-oxides showed greater thermal stability, but at 700-800 °C decomposition of the 4,5-dimethyl compound 25b lead to 1,2-di(5-methyl-2-phenyl- 1,2,3-triazol-2-yl)ethane as the major product; attempts to trap acetonitrile oxide were unsuccessful. ARKAT USA, Inc.
Copper(II)-mediated oxidation of 1,2-dioxime to furoxan
Das, Oindrila,Paria, Sayantan,Paine, Tapan Kanti
experimental part, p. 5924 - 5927 (2009/04/05)
1,2-Dioximes undergo oxidative transformation mediated by copper(II) ions in acetonitrile to form the corresponding furoxans in high yields. A series of 1,2-dioximes including aliphatic, aromatic, and heterocyclic dioximes were oxidized using these mild c
DRUGS DERIVED FROM DICLOFENAC CONTAINING NO-DONOR HETEROCYCLES, COMPOSITION AND METHOD OF INFLAMMATION TREATMENT
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Page/Page column 6-7, (2008/06/13)
The present invention refers to drugs resulting from the pharmaceutical substance diclofenac, relative to the formula. The invention further refers to a pharmaceutical composition, which involves the said drugs and a pharmaceutically adequate vehicle. It is also described a method for the treatment of inflammation through the administration of the new drugs in patients with gastric problems or subjected to long-term treatments.
Mechanism of Reaction of Isomeric Nitrolic Acids to Nitrile Oxides in Aqueous Solution
Egan, Carmel,Clery, Maurice,Hegarty, Anthony F.,Welch, Alan J.
, p. 249 - 256 (2007/10/02)
Both E and Z isomers of acetonitrolic acids 15 and 16 can be prepared when the OH group is protected by acetylation.Photoisomerization of the E-isomer resulted in quantitative conversion into the pure Z-isomer 16.Hydrolysis of the E-isomer 15 produced the parent nitrolic acid 14 which undergoes loss of NO2(1-) from the conjugate base at high pH.This reaction is however relatively slow suggesting base solubility and acidic reprecipitation as a method of purification of E-nitrolic acids.Deprotection of (Z)-O-acetylacetonitrolic acid by HO(1-) gives a highly reactive Z-nitrolic acid 17 which undergoes loss of NO2(1-) at a rate which precludes its detection; however the subsequent reactions of acetonitrile oxide (CH3CNO) formed were monitored.Rapid loss of NO2(1-) therefore occurs when there is assistance from an antiperiplanar lone pair on the imino nitrogen of the oximate anion.Arylnitrolic acids were also examined; these were in the E configuration 26 and therefore underwent slow loss of NO2(1-).Since NMR and IR data are unreliable for the assignment of configuration of nitrolic acids (relative to other oximes) a single crystal diffraction study was carried out on E-acetonitrolic acid 14.The large difference in reactivity observed for the E- and Z-nitrolic acids now permits strong supporting evidence for structural assignments.
ELECTROCHEMICAL OXIDATION OF VICINAL DIOXIMES
Niyazymbetov, M. E.,Ul'yanova, E. V.,Petrosyan, V. A.
, p. 551 - 554 (2007/10/02)
First-wave oxidation of vicinal dioximes corresponds to the transfer of two electrons and two protons to give furoxans, which are further oxidized at the potentials of the second wave.It is shown that the key step in the electrochemical cylization of vici
