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Journal of Physical Organic Chemistry, 1999
A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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A brief description and analysis of the history of and modern situation in the field of inductive effects, methods for its quantitative determination and prospects are presented, including a discussion of the underlying mechanism. Copyright © 1999 John Wiley & Sons, Ltd.
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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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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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Strongly Fluorescent Dipyrrinones — Substituent Effects.
ChemInform, 2004AbstractFor Abstract see ChemInform Abstract in Full Text.
Stefan E. Boiadjiev, David A. Lightner
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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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Additive Effects of Substituents
Nature, 1950THE present practice of analysing data relating to reaction-rates in solution in terms of the parameters of the modified Arrhenius equation, has led to a more complete understanding of the way in which polar substituents affect chemical reactivity by focusing attention on the fact
BRYNMOR JONES, J. ROBINSON
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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 on aromatic stacking interactions
Organic & Biomolecular Chemistry, 2007Synthetic supramolecular zipper complexes have been used to quantify substituent effects on the free energies of aromatic stacking interactions. The conformational properties of the complexes have been characterised using NMR spectroscopy in CDCl(3), and by comparison with the solid state structures of model compounds.
COCKROFT SL +9 more
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Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1972
The kinetic behaviour is predicted for a hypothetical polymer reaction in which the reactivity of a substituent (or other reacting entity) depends on whether zero, one or two of its neighbours have already reacted. The problem is not new, but the method of analysis used here gives solutions applicable to reactions of polymer molecules containing a ...
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The kinetic behaviour is predicted for a hypothetical polymer reaction in which the reactivity of a substituent (or other reacting entity) depends on whether zero, one or two of its neighbours have already reacted. The problem is not new, but the method of analysis used here gives solutions applicable to reactions of polymer molecules containing a ...
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