Search results for "AROMA"

showing 10 items of 1006 documents

Crystal structure and reactivity of 2-chloro-3,5-dinitrothiophene and of 2-phenylsulphonyl-3,5-dinitrothiophene with nucleophiles

1988

The geometry obtained by a crystal structure determination of the title compounds, as compared with that of the analogous benzene derivatives, along with results of ab initio calculations, is used to interpret the different SNAr reactivities in some thiophene and benzene compounds. The smaller rotation of the nitro groups with respect to the aromatic rings observed in thiophene derivatives should be considered a relevant factor in the higher reactivity in the thiophene series.

chemistry.chemical_compoundNucleophileAb initio quantum chemistry methodsNucleophilic aromatic substitutionChemistryOrganic ChemistryThiopheneOrganic chemistryReactivity (chemistry)AromaticityCrystal structureBenzeneMedicinal chemistryJournal of Heterocyclic Chemistry
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Three‐Component Castagnoli‐Cushman Reaction of 3‐Arylglutaconic Acid Anhydrides, Carbonyl Compounds, and Ammonium Acetate: a Quick and Flexible Way t…

2021

chemistry.chemical_compoundchemistryDecarboxylationComponent (thermodynamics)Organic ChemistryAromatizationOrganic chemistryPhysical and Theoretical ChemistryAmmonium acetateEuropean Journal of Organic Chemistry
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A sigma-donor with a planar six-pi-electron B2N2C2 framework: anionic N-heterocyclic carbene or heterocyclic terphenyl anion?

2006

chemistry.chemical_elementAromaticityGeneral ChemistryElectronGeneral MedicinePhotochemistryCatalysisIonchemistry.chemical_compoundPlanarchemistryTerphenylPolymer chemistryLithiumBoronCarbeneAngewandte Chemie (International ed. in English)
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Increased conformational rigidity of humic substances by oxidative biomimetic catalysis

2005

A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe(TDCPPS)Cl, was employed as a biomimetic catalyst in the oxidative coupling of terrestrial humic materials. High-performance size-exclusion chromatography (HPSEC), solid-state nuclear magnetic resonance (CPMAS-(13)C NMR), electron paramagnetic resonance (EPR), and diffuse reflectance infrared spectroscopy (DRIFT) were used to follow conformational and structural changes brought about in different humic materials by the oxidative coupling. Increase in apparent weight-average molecular weight (Mw(a)) occurred invariably for all humic substances with the oxidative polymerization catalyzed …

conformationMagnetic Resonance SpectroscopySpectrophotometry InfraredPolymers and PlasticsDiffuse reflectance infrared spectroscopy (DRIFT)Biomimetic materialsaromatic compoundgel permeation chromatographyMolecular ConformationPhotochemistryIron compoundslaw.inventionPolymerizationenvironmental managementcovalent bondlawSize exclusion chromatographyBiomimetic catalysisBiomimeticsMaterials ChemistryOrganic chemistryHumic acidElectron paramagnetic resonanceInfrared spectroscopyChromatography High Pressure Liquidchemistry.chemical_classificationSettore CHIM/03 - Chimica Generale e InorganicaCarbon IsotopesChromatographyindustryCatalystsChemistrytetra(2articleelectrophoretic mobilitybiomimetic materialNuclear magnetic resonance spectroscopyunclassified drugConformationsacetic acidpriority journalCovalent bondSpectrophotometrySynthesis (chemical)High Pressure Liquidtechnology6 dichloro 3 sulfonatophenyl)porphyrinic acid derivativeInfraredOxidation-Reductionmolecular stabilityHumic materialsoxidationSettore AGR/13 - Chimica AgrariaSupramolecular chemistryBioengineeringcomplex mixturesCatalysisCatalysisdiffuse reflectance spectroscopyhumic substanceBiomaterialsalkyl etherElectron spin resonance spectroscopycomplex formationParticle SizeNuclear magnetic resonance spectroscopyHumic Substancesfree radicalbiomimetic oxidative humicelectron spin resonanceHigh performance size exclusion chromatography (HPSEC)ferrous chloridemolecular weightsolid statecarbon nuclear magnetic resonancePolymerizationSolubilitychemical structureOxidative coupling of methaneCatalysts; Conformations; Electron spin resonance spectroscopy; Infrared spectroscopy; Iron compounds; Nuclear magnetic resonance spectroscopy; Oxidation; Polymerization; Size exclusion chromatography; Solubility; Synthesis (chemical); Biomimetic catalysis; Diffuse reflectance infrared spectroscopy (DRIFT); High performance size exclusion chromatography (HPSEC); Humic materials; Biomimetic materials; acetic acid; alkyl ether; aromatic compound; biomimetic material; ferrous chloride; free radical; tetra(26 dichloro 3 sulfonatophenyl)porphyrinic acid derivative; unclassified drug; article; carbon nuclear magnetic resonance; catalysis; catalyst; chemical structure; complex formation; conformation; covalent bond; diffuse reflectance spectroscopy; electron spin resonance; electrophoretic mobility; environmental management; gel permeation chromatography; humic substance; industry; molecular stability; molecular weight; oxidation; polymerization; priority journal; solid state; technology; Biomimetics; Carbon Isotopes; Catalysis; Chromatography High Pressure Liquid; Electron Spin Resonance Spectroscopy; Humic Substances; Magnetic Resonance Spectroscopy; Molecular Conformation; Oxidation-Reduction; Particle Size; Spectrophotometry Infraredcatalyst
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Crystal structure of (E)-4-methyl-N-{2-[2-(4-nitrobenzylidene)hydrazin-1-yl]-2-oxoethyl}benzenesulfonamideN,N-dimethylformamide monosolvate

2017

The molecule of the title Schiff base compound, C16H16N4O5S·C3H7NO, displays atransconformation with respect to the C=N double bond. The C—N and N—N bonds are relatively short compared to their normal bond lengths, indicating some degree of delocalization in the molecule. The molecule is bent at the S atom, with an S—N—C—C torsion angle of 164.48 (11)°. The dihedral angle between the two aromatic rings is 84.594 (7)°. Intermolecular N—H...O and C —H...O hydrogen bonds connect centrosymmetrically related molecules into dimers forming rings ofR33(11) andR22(10) graph-set motif stacked along theaaxis into a columnar arrangement. The molecular columns are further linked into a three-dimensional…

conformationchemistry.chemical_classificationcrystal structureSchiff baseDouble bondHydrogen bondAromaticityGeneral ChemistryCrystal structureDihedral angle010402 general chemistry010403 inorganic & nuclear chemistryCondensed Matter Physics01 natural sciences0104 chemical sciencesSulfonamidelcsh:ChemistryBond lengthSchiff basechemistry.chemical_compoundCrystallographylcsh:QD1-999chemistryGeneral Materials ScienceC—H...O hydrogen bondActa Crystallographica Section E Crystallographic Communications
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Impact flavor compounds in cooked rice cultivars from the Camargue area (France)

2010

International audience; Rice from two scented (Aychade, Fidji) and one nonscented (Ruille) cultivars from Camargue area (France) together with one Asian scented rice (Thai) were cooked and volatile compounds were extracted by dichloromethane/pentane (1;2, v/v) solvent mixture. 40 odorous compounds were noticed during GC-O analysis of the organic extracts, amongst which oct-1-en-3-one and 2-acetyl-1-pyrroline were altmost constantly perceived. Hierarchical cluster analysis (HCA) of perceived odours enabled to distinguish the groups of rice cultivars. 60 compounds were identified and quantified by GC-MS. New odour-active components of cooked rice were detected for the first time including oct…

cooked rice aromaorganic extractGC-O[SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineering[SDV.IDA]Life Sciences [q-bio]/Food engineering[SPI.GPROC]Engineering Sciences [physics]/Chemical and Process EngineeringGC-MS[SDV.IDA] Life Sciences [q-bio]/Food engineeringdetection frequencyRIZ
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Impact flavor compounds in cooked rice cultivars from Camargue area (France)

2008

International audience; Efforts have been undertaken for the last decades to promote the production of scented rice cultivars in Camargue, a traditional rice cultivation area in the south of France. Volatile compounds of cooked rice from two scented Camargue rice cultivars (Aychade and Fidji) were analysed and compared to that of a marketed Asian scented rice one (Thai)(1). Additionally volatile analysis from a cooked rice of a non-scented cultivar (Ruille) grown in Camargue was performed. (...)

cooked rice aromaorganic extract[SPI.GPROC] Engineering Sciences [physics]/Chemical and Process Engineeringgc-o[SDV.IDA]Life Sciences [q-bio]/Food engineeringfood and beverages[SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineeringgc-ms[SDV.IDA] Life Sciences [q-bio]/Food engineeringdetection frequency
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3,5-Dimethoxyphenyl 4-methylbenzenesulfonate

2017

Molecules of the title compound, C15H16O5S, are composed of a 3,5-dimethoxyphenyl moiety substituted with a toluene-4-sulfonate group. The dihedral angle between two aromatic rings is 57.23 (4)°. In the crystal, molecules are connected by weak C—H...O hydrogen bonds and S...O van der Waals interactions.

crystal structure010405 organic chemistryHydrogen bondStereochemistryChemistryAromaticityCrystal structuretosyl­atesDihedral angle010403 inorganic & nuclear chemistry01 natural sciencesMedicinal chemistryCoupling reaction0104 chemical sciencessymbols.namesakechemistry.chemical_compoundSulfonatecross-coupling reactionssymbolsMoietyvan der Waals forceIUCrData
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5-Methylbenzo[d][2,1,3]selenadiazole

2017

In the crystal of the title compound, C7H6N2Se, the molecules are arranged in rods along theb-axis direction and form dimeric units due to intermolecular Se...N contacts of 2.982 (2) Å. The molecules are further linked by weak π–π stacking interactions between the 2,1,3-selenadiazole and six-membered aromatic rings [centroid–centroid distance = 3.8509 (11) Å and ring slippage = 1.539 (3) Å].

crystal structure010405 organic chemistryStereochemistrySe...N contactsStackingselenadiazoleAromaticityCrystal structure010402 general chemistryRing (chemistry)01 natural sciences0104 chemical sciencesCrystallographychemistry.chemical_compoundchemistryπ–π interactionslcsh:QD901-999Diazolelcsh:CrystallographyIUCrData
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Crystal structure of 1-(2-fluoro­benzo­yl)-2,7-di­meth­oxy­naphthalene

2014

The asymmetric unit of the compound contains two independent conformers. Each conformer is stacked along the a axis to form columns through van der Waals inter­actions only.

crystal structureCrystallographyAromaticityGeneral ChemistryCrystal structureDihedral angleCondensed Matter PhysicsRing (chemistry)Bioinformatics1-aroyl­naphthalene compoundResearch Communicationschemistry.chemical_compoundsymbols.namesakeCrystallographynon-coplanarly accumulated aromatic rings structurechemistryQD901-999symbolsMoleculeGeneral Materials Sciencevan der Waals forceConformational isomerism1-aroylnaphthalene compoundNaphthalenespatial organizationActa Crystallographica Section E: Structure Reports Online
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