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Nitro Derivatives (nitro + derivative)
Selected AbstractsSelective Oxidation of Aromatic Amines to Nitro Derivatives using Potassium Iodide- tert -Butyl Hydroperoxide Catalytic SystemADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2009K. Rajender Reddy Abstract The direct oxidation of aromatic primary amines to the corresponding nitro compounds selectively in 47,98% yields has been achieved by using potassium iodide as catalyst and tert -butyl hydroperoxide as the external oxidant. The present catalytic system works well for both electron-rich and electron-poor substrates. [source] Nitro Derivatives of Cyclic Sulfoximides of the 1,2-Benzoisothiazole Series.CHEMINFORM, Issue 12 2003E. A. Serebryakov Abstract For Abstract see ChemInform Abstract in Full Text. [source] Theoretical Study on the Vibrational Spectra and Thermodynamic Properties for Nitro Derivatives of Benzene and AnilinesCHINESE JOURNAL OF CHEMISTRY, Issue 8 2008Gui-Xiang WANG Abstract Nitro derivatives of benzene and anilines were optimized to obtain their molecular geometries and electronic structures at a DFT-B3LYP/6-31G, level. Their IR spectra were obtained and assigned by vibrational analysis. Comparing the calculated IR spectra with these of experiments known, all the IR data obtained in this paper were considered to be reliable. Based on the frequencies scaled by 0.96 and the principle of statistic thermodynamics, the thermodynamic properties were evaluated, which were linearly related with the number of nitro and amino groups as well as the temperature, obviously showing good group additivity. [source] Analysis of interaction modes in calix[4]arene,levofloxacin complexes by quantum methodsJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 3 2006Alexandrine Lambert Abstract Host,guest interactions between chiral calix[4]arenes and the antibiotic levofloxacin are analyzed on the basis of quantum mechanical calculations at the density functional (for model systems) and semi-empirical levels. The calix[4]arene macrocycle carries two (+)-isomenthyl groups attached to opposing phenyl groups at the lower rim and different substituents (R,=,H, CH3, tBu, CH2CHCH2, COCH3 and NO2) are considered at the upper rim. Nitro derivatives are expected to form ionized complexes whereas the other derivatives should form neutral complexes with a very low stability. Copyright © 2006 John Wiley & Sons, Ltd. [source] Theoretical Study on the Vibrational Spectra and Thermodynamic Properties for Nitro Derivatives of Benzene and AnilinesCHINESE JOURNAL OF CHEMISTRY, Issue 8 2008Gui-Xiang WANG Abstract Nitro derivatives of benzene and anilines were optimized to obtain their molecular geometries and electronic structures at a DFT-B3LYP/6-31G, level. Their IR spectra were obtained and assigned by vibrational analysis. Comparing the calculated IR spectra with these of experiments known, all the IR data obtained in this paper were considered to be reliable. Based on the frequencies scaled by 0.96 and the principle of statistic thermodynamics, the thermodynamic properties were evaluated, which were linearly related with the number of nitro and amino groups as well as the temperature, obviously showing good group additivity. [source] Deposition of Cytokinesis-Related Callose in Riella helicophylla and Arabidopsis thaliana.PLANT BIOLOGY, Issue 4 2001Effects of Photolytically Altered Nifedipine Abstract: The cytokinesis-related callose deposition in cell plates and juvenile cross walls of meristematic cells was investigated in the liverwort Riella helicophylla and seedlings of Arabidopsis thaliana. The ,-1,3-glucan callose was detected by its specific staining properties with sirofluor and aniline blue by fluorescence microscopy. The photo-labile calcium antagonist nifedipine (NIF) exerted a specific promotive effect when the substance was exposed to light. The nitroso derivative of photolysed NIF was found to be the active compound which was responsible for the enhancement in callose deposition. The nitroso derivative was isolated after photolysis of NIF by UV light (365 nm) and its structure was verified with 1H-nuclear magnetic resonance and infrared spectroscopy. The characteristic absorption maximum at 770 nm in dimethyl sulfoxide was employed to determine the concentration of the nitrosopyridine in solutions by use of the molar absorption coefficient of the isolated substance. In addition, the nitro derivative of nifedipine was prepared. This nitropyridine was ineffective with respect to the stimulation of callose deposition in dividing cells. The possible mechanism of this cytotoxic effect and its implications for symplastic growth in meristems is discussed. [source] Vinylic Halogenation in 4-Alkylidenazetidin-2-onesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2007Gianfranco Cainelli Abstract The synthesis of a new family of halogenated ,-lactams by oxidative substitution of vinylic hydrogen in conjugated double bonds of 4-alkylidenazetidinones is reported. Optimised procedures give good to excellent yields of chloro, bromo, iodo and nitro derivatives. A mechanism to explain the direct vinylic substitution is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Synthesis of Some Trifluoromethylated Cyclodextrin Derivatives and Analysis of Their Properties as Artificial Glycosidases and OxidasesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 4 2007Jeannette Bjerre Abstract Cyclodextrin derivatives containing trifluoromethyl groups at C6 of the A and D rings were synthesized for the purpose of creating artificial enzymes. The compounds were synthesized by perbenzylation of ,-cyclodextrin followed by selective A,D-debenzylation according to Sina˙. Subsequent oxidation to dialdehyde with Dess,Martin periodinane followed by addition of CF3 by using Arduengo carbene and TMSCF3 led to the C6 -bistrifluoromethylated alcohols. These were either deprotected by hydrogenolysis or subjected to another round of oxidation to provide the corresponding ketones that were deprotected. The trifluoromethylated alcohols were found to be weak artificial enzymes catalysing hydrolysis of nitrophenyl glycosides at neutral pH with a kcat/kuncat of up to 56. It is proposed that this catalysis is analogues to the catalysis performed by related cyanohydrins. The trifluoro ketones were likewise weak articial enzymes catalysing oxidation of amines to nitro derivatives or alcohols to ketones with a kcat/kuncat of up to 133. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Synthesis and reactivity of sulfonamides containing boronate estersHETEROATOM CHEMISTRY, Issue 5 2004Xiao-Feng He Sulfonamides containing pinacol protected boronate ester groups have been prepared by the addition of H2NC6H4Bpin (pin = O2C2Me4) to sulfonyl chlorides p -RC6H4SO2Cl (R = CH3, NO2). Hydrogenation of the nitro derivatives afford the corresponding sulfanilamides without compromising the aryl-Bpin bond. The sulfanilamides were further functionalized to afford novel platinum complexes containing boranosulfonamides. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:369,375, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20025 [source] A theoretical investigation on the structures, densities, detonation properties, and pyrolysis mechanism of the nitro derivatives of phenolsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 9 2010Guixiang Wang Abstract The nitro derivatives of phenols are optimized to obtain their molecular geometries and electronic structures at the DFT-B3LYP/6-31G* level. Detonation properties are evaluated using the modified Kamlet,Jacobs equations based on the calculated densities and heats of formation. It is found that there are good linear relationships between density, detonation velocity, detonation pressure, and the number of nitro and hydroxy groups. Thermal stability and pyrolysis mechanism of the title compounds are investigated by calculating the bond dissociation energies (BDEs) at the unrestricted B3LYP/6-31G* level. The activation energies of H-transfer reaction is smaller than the BDEs of all bonds and this illustrates that the pyrolysis of the title compounds may be started from breaking OH bond followed by the isomerization reaction of H transfer. Moreover, the CNO2 bond with the smaller bond overlap population and the smaller BDE will also overlap may be before homolysis. According to the quantitative standard of energetics and stability as a high-energy density compound, pentanitrophenol essentially satisfies this requirement. In addition, we have discussed the effect of the nitro and hydroxy groups on the static electronic structural parameters and the kinetic parameter. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] | ||||||||||