Results 21 to 30 of about 1,305,934 (203)
Molecules, 2020 The attribution of 1H and 13C NMR signals of a library of 5-, 6- and 7-substituted 2,2-dimethylchroman-4-one derivatives is reported. Substituent effects were interpreted in terms of the Hammett equation, showing a good correlation for carbons para- to ...
Daniela Iguchi +3 more
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chemspacelab/Enhanced-Hammett: Enhanced_Hammett
, 2020 Small python library with the implementation of the Enhanced-Hammett ...
MarcoBrag
core +1 more source
Cobalt‐Catalyzed C─N Bond Formation via Metal‐Hydride Hydrogen Atom Transfer (MHAT)
Angewandte Chemie, EarlyView.Cobalt‐catalyzed metal‐hydride hydrogen atom transfer (Co‐MHAT) converts simple alkenes into C─N bonds under mild, near‐neutral conditions. A shared Co─H‐initiated radical/organocobalt intermediate is channeled into radical trapping, radical‐polar crossover, or radical ligand transfer, unifying hydroamination, hydroazidation, hydroamidation, and remote
Arman Khosravi, Ming‐Yu Ngai
wiley +2 more sources
Scientific Reports, 2023 In an attempt to prepare a low-cost and efficient acidic heterogeneous catalyst for the conversion of fructose to 5-hydroxymethylfurfural under mild reaction conditions, the acidity of halloysite was improved by covalent grafting of an acidic polyionic ...
Samahe Sadjadi +4 more
doaj +1 more source
The substituent effects on the 13c chemical shifts of the azomethine carbon atom of n-(phenyl substituted) salycilaldimines [PDF]
Journal of the Serbian Chemical Society, 2012 The Hammett correlations between 13C-NMR chemical shifts of the azomethine carbon atom and the corresponding substituent constants for thirtheen Schiff bases were established.
Drmanić Saša Ž. +3 more
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Difluoromethylenation of Alkynes: Streamlined Access to Allyl Difluorides
Angewandte Chemie, EarlyView.Stabilizing primary oxocarbenium in HF/pyridine unlocks a direct alkyne difluoromethylenation – an efficient route to synthetically‐relevant allyl difluorides in a single step. ABSTRACT A direct difluoromethylenation of alkynes has been developed using HF/pyridine as a dual acidic and fluorinating medium. The reaction proceeds via in situ generation of
Fabien Naullet +4 more
wiley +2 more sources
Solvatochromism of 5-(4-substituted arylazo)-4-phenyl-6-methyl-3-cyano-2-pyridones
Zaštita Materijala, 2018 Eight 5-(4-substituted arylazo)-4-phenyl-6-methyl-3-cyano-2-pyridones were synthesized by reaction of benzoylacetone and arendiazonium salt, followed by condensation with cyanoacetamide. Absorption spectra of all azo pyridone dyes were recorded in twelve
Gordana S. Ušćumlić +1 more
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Anwendung der Hammett-Gleichung auf die Acidität von 3-Brom-1,2,4-triazolen [PDF]
, 1967 Ionization constants of a set of 5-substituted 3-bromo-1,2,4- triazoles have been determined by potentiometric titration.
Freiberg, Walter +1 more
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Angewandte Chemie, EarlyView.Apart from (transition) metal (oxo)halides only few hosts stabilize chalcogenide cations in purely oxoanionic coordination environment. Herein, we report on five borosulfates containing the Se42+ ion and characterize the compounds using X‐ray diffraction, diffuse reflectance spectroscopy, density functional theory (DFT) calculations along with magnetic
Erich Turgunbajew +11 more
wiley +2 more sources
Studying of physicochemical properties of newly synthesized uracil derivatives
Zaštita Materijala, 2015 Uracil derivatives are potentially biologically active compounds, so the investigation of their physical and chemical properties is very important for their further application.
Jadranka A. Tot +1 more
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