Results 11 to 20 of about 363,660 (280)
Toward Universal Substituent Constants: Relating QTAIM Functional Group Descriptors to Substituent Effect Proxies [PDF]
Journal of Chemical Information and Modeling, 2023 Substituents modulate reactions, but are commonly described using proxies to their true properties. Substituent descriptors from the Quantum Theory of Atoms in Molecules are related here to these proxies, which have historically had chemically intuitable effects.
Kevin M. Lefrancois-Gagnon +1 more
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A Web Tool for Calculating Substituent Descriptors Compatible with Hammett Sigma Constants [PDF]
, 2021 Electron donating or accepting power of organic substituents is an important parameter affecting many properties of parent molecules, most notably their reactivity and pKa of ionizable groups. These substituent properties are usually described by Hammett
Peter Ertl, Ertl, Peter, Peter, Ertl
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Electrostatic Potential Topology for Probing Molecular Structure, Bonding and Reactivity
Molecules, 2021 Following the pioneering investigations of Bader on the topology of molecular electron density, the topology analysis of its sister field viz. molecular electrostatic potential (MESP) was taken up by the authors’ groups.
Shridhar R. Gadre +2 more
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Rate and equilibrium constants for the addition of N-heterocyclic carbenes into benzaldehydes : a remarkable 2-substituent effect [PDF]
, 2015 We thank the Royal Society for a University Research Fellowship (ADS), the EPSRC (CJC and RM) grant number EP/G013268/1 and the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) ERC grant agreement no 279850
Collett, Christopher John +18 more
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Bulletin of the Chemical Society of Ethiopia, 2014 Some aryl-aryl 1H pyrazoles have been synthesised by cyclization of aryl chalcones and hydrazine hydrate in the presence of SOCl2. The yields of the pyrazoles are more than 85%.
K. Ranganathan +5 more
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Synthesis, spectral correlation and insect antifeedant activities of some 2-benzimidazole chalcones
Journal of Saudi Chemical Society, 2016 Some substituted styryl 2-benzimidazole ketones have been synthesised by fly-ash:H2SO4 catalysed aldol condensation of 2-benzimidazole methyl ketone and various substituted benzaldehydes in microwave oven. The yields of these chalcones are more than 70%.
P. Janaki, K.G. Sekar, G. Thirunarayanan
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Orbital: The Electronic Journal of Chemistry, 2020 The present work reports kinetic study of the reaction of benzofuroxan and its derivatives with 2-acetylthiophene. Hammett equation was used to determine the rate of the reaction and substituent effect. Specifically, chloro, nitro and methyl substituted
Intisar Salih Ahmed, Damra Elhaj Mustafa
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Equilibrium constants and protonation site for N-methylbenzenesulfonamides
Beilstein Journal of Organic Chemistry, 2011 The protonation equilibria of four substituted N-methylbenzenesulfonamides, X-MBS: X = 4-MeO (3a), 4-Me (3b), 4-Cl (3c) and 4-NO2 (3d), in aqueous sulfuric acid were studied at 25 °C by UV–vis spectroscopy.
José A. Moreira +3 more
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Theoretical substituent electrophilicities [PDF]
, 2011 A Hammett-like equation, relating theoretical global and substituent electrophilicities, is derived for substituted ethylenes and benzoic acids, allowing the calculation of electrophilic substituent constants a..
Marcos Caroli Rezende +3 more
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Structure-Acidity-IR Spectra Correlations for p-Substituted N-Phenylsulfonylbenzamidesâ€
Molecules, 2004 The wavenumbers of the IR absorption bands of the C=O, S=O and N-H stretching vibrations for a series of p-substituted N-phenylsulfonylbenzamides were measured in trichloromethane.
Zora Sustekova +5 more
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