Results 201 to 210 of about 49,832 (253)
Some of the next articles are maybe not open access.
The Journal of Physical Chemistry A, 2005
Inductive and resonance effects of different substituents (CH3, Cl, NH3, CN, NO2) on the reactivity of the nitrogen and oxygen centers of several saturated and unsaturated hydroxylamine derivates toward hard and soft electrophiles are analyzed in terms of various conceptual DFT based descriptors calculated using B3LYP/6-311G** method.
Pratim K, Chattaraj +3 more
openaire +2 more sources
Inductive and resonance effects of different substituents (CH3, Cl, NH3, CN, NO2) on the reactivity of the nitrogen and oxygen centers of several saturated and unsaturated hydroxylamine derivates toward hard and soft electrophiles are analyzed in terms of various conceptual DFT based descriptors calculated using B3LYP/6-311G** method.
Pratim K, Chattaraj +3 more
openaire +2 more sources
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
openaire +3 more sources
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
openaire +2 more sources
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
openaire +2 more sources
Collection of Czechoslovak Chemical Communications, 1995
The paper deals with chemometric analysis of the inductive effect. The notion of inductive effect is discussed, and unambiguous definitions are given for the notions of triad: reaction centre-basic skeleton-substituent, and the therewith connected definitions of inductive effect.
Oldřich Pytela, Aleš Halama
openaire +1 more source
The paper deals with chemometric analysis of the inductive effect. The notion of inductive effect is discussed, and unambiguous definitions are given for the notions of triad: reaction centre-basic skeleton-substituent, and the therewith connected definitions of inductive effect.
Oldřich Pytela, Aleš Halama
openaire +1 more source
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
openaire +1 more source
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
openaire +2 more sources
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
openaire +2 more sources
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
openaire +2 more sources
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
openaire +1 more source
Substituent Effects on the Cooperativity of Halogen Bonding
The Journal of Physical Chemistry A, 2013DFT calculations (B97-1) with the 6-31+G(d,p)-LanL2DZdp basis set were used to analyze the intermolecular interactions in 4-Z-Py···XCN···XCN triads (Z = H, F, OH, OCH3, CH3, NH2, NO2, and CN; Py = pyridine; and X = Cl and Br) that are connected by halogen-bond interactions. To understand the properties of the systems better, the corresponding dyads are
Solimannejad, Mohammad +2 more
openaire +3 more sources