- Synthesis and structural characterization of tris(2-pyridonyl)methyl complexes of zinc and thallium: A new class of metallacarbatranes and a monovalent thallium alkyl compound
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Tris(2-pyridonyl)methanes may be synthesized via the reactions of the respective 2-pyridone with CHX3 (X = Cl, Br) and K2CO 3 in the presence of [Bun4N]Br, followed by acid-catalyzed isomerization wit
- Al-Harbi, Ahmed,Rong, Yi,Parkin, Gerard
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Read Online
- Urea-functionalized M4L6 cage receptors: Anion-templated self-assembly and selective guest exchange in aqueous solutions
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We present an extensive study of a novel class of de novo designed tetrahedral M4L6 (M = Ni, Zn) cage receptors, wherein internal decoration of the cage cavities with urea anion-binding groups, via functionalization of the organic components L, led to selective encapsulation of tetrahedral oxoanions EO4n- (E = S, Se, Cr, Mo, W, n = 2; E = P, n = 3) from aqueous solutions, based on shape, size, and charge recognition. External functionalization with tBu groups led to enhanced solubility of the cages in aqueous methanol solutions, thereby allowing for their thorough characterization by multinuclear (1H, 13C, 77Se) and diffusion NMR spectroscopies. Additional experimental characterization by electrospray ionization mass spectrometry, UV-vis spectroscopy, and single-crystal X-ray diffraction, as well as theoretical calculations, led to a detailed understanding of the cage structures, self-assembly, and anion encapsulation. We found that the cage self-assembly is templated by EO4n- oxoanions (n ≥ 2), and upon removal of the templating anion the tetrahedral M4L6 cages rearrange into different coordination assemblies. The exchange selectivity among EO4n- oxoanions has been investigated with 77Se NMR spectroscopy using 77SeO42- as an anionic probe, which found the following selectivity trend: PO 43- ? CrO42- > SO 42- > SeO42- > MoO 42- > WO42-. In addition to the complementarity and flexibility of the cage receptor, a combination of factors have been found to contribute to the observed anion selectivity, including the anions' charge, size, hydration, basicity, and hydrogen-bond acceptor abilities.
- Custelcean, Radu,Bonnesen, Peter V.,Duncan, Nathan C.,Zhang, Xiaohua,Watson, Lori A.,Van Berkel, Gary,Parson, Whitney B.,Hay, Benjamin P.
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- Substituted 2,2′-bipyridines by nickel catalysis: 4,4′-Di- tert -butyl-2,2′-bipyridine
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A simple, ligand-free synthesis of the important bipyridyl ligand 4,4′-di-tert-butyl-2,2′-bipyridine is presented. 5,5′-Bis(trifluoromethyl)-2,2′-bipyridine is also synthesized by the same protocol. The syntheses efficiently couple the parent 2-chloropyridines by a nickel-catalyzed dimerization with manganese powder as the terminal reductant. Georg Thieme Verlag Stuttgart New York.
- Buonomo, Joseph A.,Everson, Daniel A.,Weix, Daniel J.
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Read Online
- Ozone-Mediated Amine Oxidation and Beyond: A Solvent-Free, Flow-Chemistry Approach
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Ozone is a powerful oxidant, most commonly used for oxidation of alkenes to carbonyls. The synthetic utility of other ozone-mediated reactions is hindered by its high reactivity and propensity to overoxidize organic molecules, including most solvents. This challenge can largely be mitigated by adsorbing both substrate and ozone onto silica gel, providing a solvent-free oxidation method. In this manuscript, a flow-based packed bed reactor approach is described that provides exceptional control of reaction temperature and time to achieve improved control and chemoselectivity over this challenging transformation. A powerful method to oxidize primary amines into nitroalkanes is achieved. Examples of pyridine, C-H bond, and arene oxidations are also demonstrated, confirming the system is generalizable to diverse ozone-mediated processes.
- Skrotzki, Eric A.,Vandavasi, Jaya Kishore,Newman, Stephen G.
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p. 14169 - 14176
(2021/06/30)
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- MODULATORS OF CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR
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This disclosure provides modulators of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), pharmaceutical compositions containing at least one such modulator, methods of treatment of cystic fibrosis using such modulators and pharmaceutical compositions, and processes for making such modulators.
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Paragraph 00185; 00658
(2021/02/19)
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- Organometallic complex and Organic light emitting diode comprising the same
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An organometallic complex and an organic light emitting device including the same are disclosed. (by machine translation)
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Paragraph 0128; 0131-0133; 0174; 0178-0179
(2020/07/01)
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- Electrochemical Deoxygenation of N-Heteroaromatic N -Oxides
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An electrochemical method for the deoxygenation of N-heteroaromatic N -oxide to give the corresponding N-heteroaromatics has been developed. Several classes of N-heterocycles such as pyridine, quinoline, isoquinoline, and phenanthridine are tolerated. The electrochemical reactions proceed efficiently in aqueous solution without the need for transition-metal catalysts and waste-generating reducing reagents.
- Xu, H.-C.,Xu, P.
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supporting information
p. 1219 - 1221
(2019/06/08)
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- Visible Light-Mediated Decarboxylative Alkylation of Pharmaceutically Relevant Heterocycles
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A net redox-neutral method for the decarboxylative alkylation of heteroarenes using photoredox catalysis is reported. Additionally, this method features the use of simple, commercially available carboxylic acid derivatives as alkylating agents, enabling the facile alkylation of a variety of biologically relevant heterocyclic scaffolds under mild conditions.
- Sun, Alexandra C.,McClain, Edward J.,Beatty, Joel W.,Stephenson, Corey R. J.
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supporting information
p. 3487 - 3490
(2018/06/26)
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- Nickel-catalyzed C–H trifluoromethylation of pyridine N-oxides with Togni's reagent
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The first nickel-catalyzed C–H trifluoromethylation of pyridine N-oxides with Togni's reagent has been achieved. Trifluoromethylation proceeds smoothly under mild conditions with moderate functional group compatibility. Notable advantages of this method include the using of low cost of nickel catalyst, and its simple convenient operation.
- Gao, Xianying,Geng, Yang,Han, Shuaijun,Liang, Apeng,Li, Jingya,Zou, Dapeng,Wu, Yangjie,Wu, Yusheng
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supporting information
p. 1551 - 1554
(2018/03/23)
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- ORGANIC COMPOUND AND ORGANIC LIGHT-EMITTING ELEMENT USING THE SAME
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PROBLEM TO BE SOLVED: To provide a compound which has an electron-donating property and is stable in the atmosphere. SOLUTION: The organic compound is represented by general formula [1] (where n represents an integer from 0 to 3 inclusive; R1 and R4 each represent an alkyl group or an aryl group selected from a phenyl group, a naphthyl group, a biphenyl group, a terphenyl group, a phenanthrenyl group, a fluorenyl group, and a fluoranthenyl group; when R1 or R4 is an aryl group, the aryl group may further have an alkyl group; R2 and R3 each represent an alkyl group or an aryl group selected from a phenyl group, a naphthyl group, a biphenyl group, a terphenyl group, a phenanthryl group, a fluorenyl group, and a fluoranthenyl group; when R2 or R3 is an aryl group, the aryl group may further have an alkyl group, a phenyl group, or a naphthyl group; when R1 and R4 are alkyl groups, R2 and R3 are aryl groups; and when R2 and R3 are alkyl groups, R1 and R4 are aryl groups). SELECTED DRAWING: None COPYRIGHT: (C)2017,JPO&INPIT
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Paragraph 0160; 0161
(2017/07/01)
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- A lipase-glucose oxidase system for the efficient oxidation of: N -heteroaromatic compounds and tertiary amines
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In this work, a lipase-glucose oxidase system has been designed and proven to be an efficient system for the oxidation of N-heteroaromatic compounds and tertiary amines. This dual-enzyme system not only displays environmental friendliness, but also demonstrates its huge potential in industrial applications.
- Yang, Fengjuan,Zhang, Xiaowen,Li, Fengxi,Wang, Zhi,Wang, Lei
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supporting information
p. 3518 - 3521
(2016/07/06)
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- Metal-Free, Phosphonium Salt-Mediated Sulfoximination of Azine N-Oxides: Approach for the Synthesis of N-Azine Sulfoximines
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Herein, we report a simple and metal-free method for the synthesis of N-azine sulfoximines by the nucleophilic substitution of azine N-oxides with NH-sulfoximines. The present method works at room temperature with wide functional group compatibility and gives several unprecedented N-azine sulfoximines. The reaction conditions were also found suitable with enantiopure substrates and furnished products without any racemization. It also finds an application in the sulfoximination of azine-based functional molecules such as 2,2′-bipyridine, 1,10-phenanthroline, and quinine.
- Aithagani, Sravan Kumar,Kumar, Mukesh,Yadav, Mahipal,Vishwakarma, Ram A.,Singh, Parvinder Pal
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p. 5886 - 5894
(2016/07/23)
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- Stereo- and Regioselective Alkyne Hydrometallation with Gold(III) Hydrides
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The hydroauration of internal and terminal alkynes by gold(III) hydride complexes [(C^N^C)AuH] was found to be mediated by radicals and proceeds by an unexpected binuclear outer-sphere mechanism to cleanly form trans-insertion products. Radical precursors such as azobisisobutyronitrile lead to a drastic rate enhancement. DFT calculations support the proposed radical mechanism, with very low activation barriers, and rule out mononuclear mechanistic alternatives. These alkyne hydroaurations are highly regio- and stereospecific for the formation of Z-vinyl isomers, with Z/E ratios of >99:1 in most cases.
- Pintus, Anna,Rocchigiani, Luca,Fernandez-Cestau, Julio,Budzelaar, Peter H. M.,Bochmann, Manfred
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supporting information
p. 12321 - 12324
(2016/10/13)
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- Heteroleptic Ir(III) phosphors with bis-tridentate chelating architecture for high efficiency OLEDs
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A bis-tridentate iridium complex represented by a formula (I): where R3 to R8, R21 to R23, R9, R10, X1, X2, and X3 are as defined in the specification.
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Page/Page column 12
(2016/01/09)
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- 2-Amino-1,3,5-triazine chemistry: hydrogen-bond networks, Takemoto thiourea catalyst analogs, and olfactory mapping of a sweet-smelling triazine
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Abstract The chemistry of 4,6-dialkyl-2-amino-1,3,5-triazines with bulky alkyl substituents was investigated and their use as building blocks for preparing chiral thiourea organocatalysts explored. Reaction of ammonia with 4,6-di-tert-butyl-2-chloro-1,3,5-triazine gave 4,6-di-tert-butyl-1,3,5-triazin-2-amine which formed extended hydrogen-bond networks in the solid state according to X-ray crystallography. Selected heterocyclic amines were converted to isothiocyanates, and the latter reacted with (S,S)-2-(dimethylamino)cyclohexylamine to give enantiopure 1-hetaryl-3-[2-(dimethylamino)cyclohexyl]thioureas, with hetaryl representing either 4,6-dimethyl-1,3-diazin-2-yl, 4,6-diisopropyl-1,3,5-triazin-2-yl, or 4,6-di-tert-butyl-1,3,5-triazin-2-yl groups. These compounds are structural analogs of Takemotos's chiral thiourea organocatalysts (1-[3,5-bis(trifluoromethyl)phenyl]-3-[(1S,2S)-2-(dimethylamino)cyclohexyl]thiourea) with an aza-aryl instead of the 3,5-bis(trifluoromethyl)phenyl group. They feature a strong intramolecular N-H to N-1 hydrogen bond, as shown by X-ray crystallography of 1-(4,6-di-tert-butyl-1,3,5-triazin-2-yl)-3-[2-(dimethylamino)cyclohexyl]thiourea in the solid state and by 1H NMR spectroscopy of all derivatives in CDCl3 solution, which prevents them from acting as bifunctional organocatalyst. In the reaction of 4,6-di-tert-butyl-2-chloro-1,3,5-triazine with ammonia, 4,6-di-tert-butyl-2-ethoxy-1,3,5-triazine was identified as side-product displaying a mildly sweet, floral odor that is unusual for a 1,3,5-triazine. Analogs (>35) of 4,6-di-tert-butyl-2-ethoxy-1,3,5-triazine were prepared to define the important structural factors of the olfactophore.
- Hintermann, Lukas,P?thig, Alexander,Xiao, Li
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supporting information
p. 1529 - 1539
(2015/08/18)
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- Expedient synthesis of α-(2-azaheteroaryl) acetates via the addition of silyl ketene acetals to azine- N -oxides
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A new and expedient synthesis of α-(2-azaheteroaryl) acetates is presented. The reaction proceeds rapidly under mild conditions via the addition of silyl ketene acetals to azine-N-oxides in the presence of the phosphonium salt PyBroP. This procedure affords diverse α-(2-azaheteroaryl) acetates which are highly desirable components/building blocks in molecules of pharmaceutical interest but are traditionally challenging to synthesize via contemporary methods. The reaction optimization and mechanism as well as a novel electronically enhanced PyBroP derivative are described.
- Londregan, Allyn T.,Burford, Kristen,Conn, Edward L.,Hesp, Kevin D.
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supporting information
p. 3336 - 3339
(2014/07/08)
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- Synthesis of alkyl aryl(heteroaryl)acetates from N-oxides, 1,1-difluorostyrenes, and alcohols
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Derivatives of aryl(heteroaryl)acetic acids or aryl(heteroaryl)methanes are formed from imidazole or thiazole N-oxide, 1,1-difluorostyrene, and an alcohol, amine, or water in a three-component reaction, which probably occurs via 1,3-dipolar cycloaddition.
- Loska, Rafal,Szachowicz, Katarzyna,Szydlik, Dorota
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supporting information
p. 5706 - 5709
(2013/12/04)
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- PYRIDINE AND ISOQUINOLINE DERIVATIVES AS SYK- AND JAK-KINASE INHIBITORS
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The present invention relates to a compound of formula (I), to the process for preparing such compounds and to their use in the treatment of a pathological condition or disease susceptible to amelioration by inhibition of Syk kinase and/or Janus kinases.
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Page/Page column 51-52
(2012/04/17)
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- Charged cyclometalated iridium(III) complexes that have large electrochemical gap
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Bis-cyclometalated cationic Ir(III) diimine complexes [Ir(C^N) 2(N^N)](PF6) with 1-phenylpyrazoles (C^N) and 1-(4′-tert-butyl-2′-pyridyl)pyrazole (N^N) are white solids that have absorption onset below 425 nm and electrochemical gap of up to 3.5 V.
- Shavaleev, Nail M.,Scopelliti, Rosario,Baranoff, Etienne,Graetzel, Michael,Nazeeruddin, Mohammad K.
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scheme or table
p. 316 - 319
(2012/04/23)
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- Bright blue phosphorescence from cationic bis-cyclometalated iridium(III) isocyanide complexes
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We report new bis-cyclometalated cationic iridium(III) complexes [(CN) 2Ir(CN-tert-Bu)2](CF3SO3) that have tert-butyl isocyanides as neutral auxiliary ligands and 2-phenylpyridine or 2-(4'- fluorophenyl)-R-pyridines (where R is 4-methoxy, 4-tert-butyl, or 5-trifluoromethyl) as CN ligands. The complexes are white or pale yellow solids that show irreversible reduction and oxidation processes and have a large electrochemical gap of 3.58-3.83 V. They emit blue or bluegreen phosphorescence in liquid/solid solutions from a cyclometalatingligand- centered excited state. Their emission spectra show vibronic structure with the highest-energy luminescence peak at 440-459 nm. The corresponding quantum yields and observed excitedstate lifetimes are up to 76% and 46 μs, respectively, and the calculated radiative lifetimes are in the range of 46-82 μs. In solution, the photophysical properties of the complexes are solvent-independent, and their emission color is tuned by variation of the substituents in the cyclometalating ligand. For most of the complexes, an emission color red shift occurs in going from solution to neat solids. However, the shift is minimal for the complexes with bulky tert-butyl or trifluoromethyl groups on the cyclometalating ligands that prevent aggregation. We report the first example of an iridium(III) isocyanide complex that emits blue phosphorescence not only in solution but also as a neat solid.
- Shavaleev, Nail M.,Monti, Filippo,Costa, Ruben D.,Scopelliti, Rosario,Bolink, Henk J.,Orti, Enrique,Accorsi, Gianluca,Armaroli, Nicola,Baranoff, Etienne,Graetzel, Michael,Nazeeruddin, Mohammad K.
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scheme or table
p. 2263 - 2271
(2012/05/20)
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- Pyridine- and isoquinoline-derivatives as Syk and JAK kinase inhibitors
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The present invention relates to a compound of formula (I), to the process for preparing such compounds and to their use in the treatment of a pathological condition or disease susceptible to amelioration by inhibition of Syk kinase and/or Janus kinases.
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Paragraph 0159
(2013/03/26)
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- Pyrrolopyrazine Kinase Inhibitors
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The present invention relates to the use of novel pyrrolopyrazine derivatives of Formula I, wherein the variables n, p, q, Q, X, X′ and Y are defined as described herein, which inhibit JAK and SYK and are useful for the treatment of auto-immune and inflammatory diseases.
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Page/Page column 97
(2011/10/10)
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- Synthesis of unsymmetrically substituted bipyridines by palladium-catalyzed direct C-H arylation of pyridine N -oxides
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Chemical equations presented. Substituted bipyridines were efficiently prepared by direct coupling between pyridine N-oxides and halopyridines using a palladium catalyst. Pyridine N-oxides with electron-withdrawing substitutents gave the best yields. This method allows the convenient preparation of 2,2′-, 2,3′-, and 2,4′-bipyridines which are useful as functionalized ligands for metal complexes or as building blocks for supramolecular architectures.
- Duric, Sasa,Tzschucke, C. Christoph
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supporting information; experimental part
p. 2310 - 2313
(2011/06/28)
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- Intra- and intermolecular C-H activation by bis(phenolate) pyridineiridium(III) complexes
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A bis(phenolate)pyridine pincer ligand (henceforth abbreviated as ONO) has been employed to support a variety of iridium complexes in oxidation states I, III, and IV. Complexes (ONO)IrL2Me (L = PPh3, PEt 3) react with I2 to cleave the Ir-C bond and liberate MeI, apparently via a mechanism beginning with electron transfer to generate an intermediate Ir(IV) complex, which can be isolated and characterized for the case L = PEt3. The PPh3 complex is transformed in benzene at 65 °C to the corresponding phenyl complex, with loss of methane, and subsequently to a species resulting from metalation of a PPh3 ligand. Labeling and kinetics studies indicate that PPh3 is the initial site of C-H activation, even though the first observed product is that resulting from intermolecular benzene activation. C-H activation of acetonitrile has also been observed.
- Fu, Ross,Bercaw, John E.,Labinger, Jay A.
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experimental part
p. 6751 - 6765
(2012/02/05)
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- A simple and efficient method for the preparation of N- heteroaromatic N-oxides
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Urea-hydrogen peroxide/formic acid system has shown utility for mild and safe N-oxidation of N-heteroaromatic compounds.
- Balicki, Roman,Golinski, Jerzy
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p. 1529 - 1534
(2007/10/03)
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- Alpha-substituted pyrimidine-thioalkyl and alkylether compounds as inhibitors of viral reverse transcriptase
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The subject invention relates to pyrimidine-thioalkyl and alkylether compounds of Formula (I) and pyrimidine-thioalkyl and alkylethers of Formula (IA), namely the compounds of Formula (I) where R 4 is selected from the group consisitng of --H or --NR 15 R 16 where R 15 is --H and R 16 is --H, C 1 -C 6 alkyl, NH 2 or R 15 and R 16 taken together with the --N form 1-pyrrolidino, 1-morpholino or 1-piperidino; and R 6 is selected from the group consisting of --H, or halo (preferably --Cl); with the overall proviso that R 4 and R 6 are not both --H. The compounds of Formula (IA) are useful in the treatment of individuals who are HIV positive being inhibitors of viral reverse transcriptase. STR1
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- Synthesis of chiral nonracemic 4-trans-substituted pipecolic acid derivatives
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The syntheses and resolutions of enantiomerically enriched 4-phenyl, 4- tert-butyl, and 4-isopropyl pipecolic acids are described. Optically active diastereomers were prepared by diastereomeric salt formation with the chiral base, L-tyrosine hydrazide, to
- Keenan, Terence P.,Yaeger, David,Holt, Dennis A.
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p. 4331 - 4341
(2007/10/03)
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- Synthesis, Crystal Structure and Catalytic Activities of
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The compound H2bbpc , which has good solubility in organic solvents, has been prepared.Reaction of with H2bbpc in ethanol and in the presence of triethylamine gave , the crystal structure of which has been determined.This complex is an active catalyst for alkene epoxidation by PhIO, cyclopropanation of styrene by ethyl diazoacetate and aziridination of styrene by PhINO2SC6H4Me-p.Its cyclic voltammogram in dichloromethane showed a reversible Ru(III)-Ru(II) couple at -0.55 V and an oxidation couple at 0.32 V.
- Ko, Po-Hung,Chen, Tai-Yuen,Zhu, Jin,Cheng, Kin-Fai,Peng, Shie-Ming,Che, Chi-Ming
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p. 2215 - 2220
(2007/10/03)
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- Antipruritic composition
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An antipruritic composition for an oral medicine, injection, and external medicine, comprising an effective amount of a chelated zinc (e.g., zinc picolinate) as an antipruritic agent.
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- An Excellent Method for the Mild and Safe Oxidation of N-Heteroaromatic Compounds and Tertiary Amines
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Selective, mild and safe N-oxidation of N-heteroaromatic compounds and tertiary amines affording high product yields was achieved by using the H2O2-urea/phthalic anhydride system. Key Words: N-Oxidation / Hydrogen peroxide / Urea / Phthalic anhydride
- Kaczmarek, Lukasz,Balicki, Roman,Nantka-Namirski, Pawel
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p. 1965 - 1966
(2007/10/02)
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- An Improved Synthesis of Homoproline and Derivatives
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An improved, general synthesis of substituted homoprolines has been developed by using readily available substituted pyridines (1).A key step in this synthetic procedure involves the known conversion of pyridine-N-oxides to 2-cyanopyridines (3) in nearly quantitative yields.The resulting nitriles are hydrolyzed to the corresponding pyridine-2-carboxylic acids (4).Subsequent reduction of the aromatic ring with PtO2/H2 gives the homoprolines (5) in good yields as racemic cis isomers.This procedure also can be utilized for the preparation of 5,6-benzohomoprolines fromthe appropriate quinoline precursors.The N-tert-butyloxycarbonyl (Boc) derivatives of these amino acids (useful intermediates for peptide synthesis) were also prepared in good yields.
- Shuman, Robert T.,Ornstein, Paul L.,Paschal, Jonathan W.,Gesellchen, Paul D.
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p. 738 - 741
(2007/10/02)
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- Investigation on Factors Ruling Catalytic Efficiency and Chemical Stability of Mn(III) Porphyrins in HOCl Olefin Epoxidation: Conditions for Practical Applications
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The use of stable Mn(III) porphyrins (P), e.g. 2-4, and of imidazole or pyridine axial ligands (L), 8-10, entirely soluble in the organic phase has allowed an extensive investigation of the factors ruling the catalytic activity of porphyrins in the olefin
- Banfi, Stefano,Montanari, Fernando,Quici, Silvio
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p. 1850 - 1859
(2007/10/02)
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- New description of substituent effect on electronic spectra by means of substituent constants-VI. Ultraviolet spectra of 4-substituted pyridine N-oxides and blue shifted iodine bands of their EDA complexes with iodine
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Electronic spectra of 4-substituted pyridine N-oxides and their EDA complexes with iodine were studied.The substituent effect on the near u.v. 1A1 intramolecular CT bands of the N-oxides and on the blue shifted iodine bands caused by CT complex formation are discussed in terms of a general equation, theoretically derived in order to describe the substituent effect on electronic spectra by means of substituent constants.The results are quite successful and supported by semi-empirical SCFMO-Cl calculations.Based on the results mentioned above, the character of n-? type N-oxide-iodine CT complexes is also examined.The complex formation constants(log K) and pKa values of the N-oxides correlate especially well, indicating that the CT interaction mechanism cannot be neglected in proton addition reactions such as hydrogen bonding and pKa values.
- Uno, Bunji,Kano, Kenji,Kaida, Naoki,Kubota, Tanekazu
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p. 937 - 944
(2007/10/02)
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- An Electron Spin Resonance and Voltametric Investigation of Some 2-Mono- and 2,4-Di-substitued Pyridinyl Radicals
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The chemical reduction of some 2-monosubstitued and 2,4-disubstitued pyridinium ions has been investigated by means of e.s.r. spectroscopy and the result compared with those of an electrochemical study on the same species.By combining the electrochemical and e.s.r. data, a scale of stability has been determined for the investigated pyridinyl radicals.N-Methyl-2-cyanopyridinyl, wich was found to be too unstable to be observed, eventually evolved to the 2,4-dicyano-substitued radical.E.s.r. studies have also been carried out on the structurally similar, although more persistent, N-germylpyridinyls.
- Greci, Lucedio,Alberti, Angelo,Carelli, Italo,Trazza, Antonio,Casini, Antonio
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p. 2013 - 2018
(2007/10/02)
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- KINETICS OF THE N OXIDATION OF SOME COMPOUNDS OF THE PYRIDINE SERIES WITH PERBENZOIC ACID IN CHLOROFORM AND AQUEOUS DIOXANE
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A comparative study of the kinetics of the N oxidation of 19 derivatives of the pyridine series with perbenzoic acid in choroform and aqueous dioxane at 20, 25, 30, and 35 deg C was made.The rate constants, the parameters of the Arrhenius equation, and the activation energies of the N oxidation of the indicated monoazines were determined.The scale of the reactivities of the derivatives of the pyridine series was calculated within the framework of the Pearson hard-soft acid-base concept.
- Lohkov, R.E.
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p. 264 - 271
(2007/10/02)
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