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Stereoelectronic Substituent Effects
ChemInform, 2006AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Bols, Mikael, Jensen, Henrik Helligsø
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The Journal of Physical Chemistry A, 2009
Carbon 1s ionization energies have been measured for all of the carbon atoms in eight fluoromethylbenzenes. Enthalpies of protonation have been calculated for protonation at all of the ring carbons in the same molecules. These data together with previously reported data on fluorobenzenes and methylbenzenes provide the basis for studying the additivity ...
Thomas X, Carroll +3 more
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Carbon 1s ionization energies have been measured for all of the carbon atoms in eight fluoromethylbenzenes. Enthalpies of protonation have been calculated for protonation at all of the ring carbons in the same molecules. These data together with previously reported data on fluorobenzenes and methylbenzenes provide the basis for studying the additivity ...
Thomas X, Carroll +3 more
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Substituent effects. 4. Nature of substituent effects at carbonyl groups
Journal of the American Chemical Society, 1992The effect of substituents on the properties of acyl derivatives has been examined. Geometry optimizations were carried out at the MP2/6-31G * theoretical level, followed by calculation of energies at the MP3/6-311++G ** level. The energies were studied via isodamic reactions with ethane leading to acetone and a methyl derivative.
Kenneth B. Wiberg +3 more
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THE EFFECT OF SUBSTITUENTS ON PHTHALOCYANINE PHOTOCYTOTOXICITY
Photochemistry and Photobiology, 1987AbstractPhthalocyanine (Pc) dyes are a class of photosensitizers that are being considered for use in the photodynamic therapy of cancer. A final choice for the most useful drug demands phototoxicity screening of various structurally related Pc dyes, such as those with different substituents at the peripheral benzene rings.
I, Rosenthal +5 more
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Substituent Effects on Folding in Cyclotetraphosphane
Chemische Berichte, 1991Ab initio quantum chemical calculations evidence a very flat potential hypersurface for folding of parent cyclotetraphosphane. This is in accord with a corresponding vibrational analysis. Electronegative substituents increase folding of the fourmembered ring system.
Schoeller, Wolfgang, BUSCH, T
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Ligand substituents effect on 10Dq
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2012Reaction of 5,6-dihydro-5,6-epoxy-1,10-phenanthroline (L) with Ni(ClO(4))(2)·6H(2)O in methanol in 3:1M proportion at room temperature yields [NiL(3)](ClO(4))(2)·2H(2)O. The X-ray crystal structure of the cation NiL(3)(2+) has been determined. Aminolysis of the three epoxide rings in NiL(3)(2+) by 4-substituted anilines in boiling water without any ...
Nirmal K, Shee +2 more
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The Substituent Effect. 15. The LSFE Treatment of Substituent Effects on Basicities of Pyridines
Bulletin of the Chemical Society of Japan, 1980Abstract The relative dissociation constants of meta and para substituted pyridinium ions in H2O at 25 °C were collected from a number of sources. To understand the actual substituent effects with a combination of inductive (I) and pi-electronic (Pi) effect components, the LSFE equation has been employed statistically for each of the ...
Masami Sawada +4 more
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Substituent effects of halopyridines
Journal of Molecular Structure, 2008Abstract The electronic structures of a number of halopyridines were measured by HeI photoelectron (PE) spectroscopy. Combined the empirical arguments and theoretical methods, the observed PE bands were interpreted. The careful analysis of measured π-orbital and halogen lone pair ionization energies enable us to describe substituent effects in terms ...
Chun-Ping Ma, Li Yao, Mao-Fa Ge
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Substituent effects in cyclohexenes
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1980The effects of the C1-CH3 group in the13C spectra of trans-4,5-dimethylcyclohex-4-ene-1,2-dicarboxylic and syn-txans-Δ4-octalin-1,2-dicarboxylic acid and their diesters show the existence in solution of a considerable proportion of the trans-a,a forms of these compounds.
V. A. Denisenko +3 more
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Substituent effects in the napthalene system. [PDF]
Forty-four substituted 2-naphthoic acids, two substituted 1-naphthoic acids and some of their corresponding methyl esters have been synthesized. The substituents are the nitro, cyano, fluoro, chloro, bromo, iodo, methyl, hydroxyl, methoxy, amino and dimethylamino groups.
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