Results 11 to 20 of about 17,649 (161)
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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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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Excited state substituent constants: to Hammett or not? [PDF]
Structural Chemistry, 2011 In this study, an answer has been sought to several questions: Can substituents’ impact on the electronic properties of molecules in the excited singlet states be summed up by a set of substituent constants? Are the well known, ground state Hammett σ constants practical for this purpose? To answer these questions, the potentials and charges on atoms of
Sadlej-Sosnowska, Nina, Kijak, Michał
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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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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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Kinetics of the reaction of 5-substituted orotic acids with diazodiphenylmethane [PDF]
Journal of the Serbian Chemical Society, 2004 Rate konstants for the reaction of eight 5-substituted orotic acids with diazodiphenylmethane (DDM) in dimethylformamide (DMF) were determined at 30 ºC by the known spectrophotometricmethod.
Jovanović Bratislav Ž. +2 more
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Journal of Saudi Chemical Society, 2014 Thirteen optically active (αS,βR) 1-naphthyl keto-oxiranes (1-naphthyl-4-yl[3-(substituted phenyl)oxiran-2-yl]methanones) have been synthesised by phase transfer catalysed epoxidation of 1-naphthyl chalcones. The yields of oxiranes are more than 95%. The
G. Thirunarayanan
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New description of the substituent effect on electronic spectra by means of substituent constants
Journal of Molecular Structure: THEOCHEM, 1991 著者らは近年,電子スペクトルに対する置換基効果を置換基定数で記述する新しい方法を研究してきた。電子スペクトルで測定される一重項あるいは三重項遷移エネルギー(1.3Euv)は, Swain らの FR 置換基定数あるいは湯川らの置換基定数 (σi ,σπ+,σπ-)を用いて, 1.3EUV=aF+bR+C, 1,3EUV=ασi+βσπ++γσπ-+Cと記述された。そして,これらは共役系の n-π* 吸収帯を初め,共役系および脂肪族系の n-π* 吸収帯,分子内電荷移動吸収帯,分子化合物の分子間電荷移動吸収帯およびそれら錯体形成による成分化合物自身の吸収帯などに対する置換基効果に適用できる一般式であることを明らかにした。さらに,ベンゼン置換体の吸収帯を用いて,これらの式の適用限界を議論した ...
Bunji UNO, Tanekazu KUBOTA
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