Results 181 to 190 of about 10,994 (228)

Photochemistry of 5-aminoquinoline in protic and aprotic solvents

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011
Photophysical properties of 5-aminoquinoline (5AQ) have been investigated in various non-polar and polar (protic and aprotic) solvents using steady state and time resolved fluorescence. In aprotic solvents, the spectral maxima depend on the polarity. However, in protic solvents both the fluorescence intensity as well decay time show decrease depending ...
Jagat P, Bridhkoti, Hirdyesh, Mishra, H C, Joshi, Sanjay, Pant   +3 more
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Photooxidation of Co-thiolato complexes in protic and aprotic solvents

Chemical Communications, 2006
Protic solvents decrease the susceptibility of the thiolate ligand in Co(III) thiolato complexes toward attack by singlet oxygen, but greatly increase the conversion of the peroxidic intermediate to the sulfenato product.
Billy, Hernandez, Yanju, Wang, Dong, Zhang, Matthias, Selke   +3 more
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Selective Recognition of Alkyl Pyranosides in Protic and Aprotic Solvents

Journal of the American Chemical Society, 2008
The design and synthesis of receptors capable of selective, noncovalent recognition of carbohydrates continues to be a signature challenge in bioorganic chemistry. We report a new generation of tripodal receptors incorporating three pyridine (compound 2) or quinoline (compound 3) rings around a central cyclohexane core for use in molecular recognition ...
Prakash B, Palde, Peter C, Gareiss, Benjamin L, Miller   +2 more
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Aminolysis of oxime ethers in protic and aprotic solvents

Journal of the Chemical Society, Perkin Transactions 2, 1989
Reactions of oxime ethers with the primary amines, n-propyl-, n-butyl-, n-pentyl-, and n-hexylamine in DMSO, DMF, and MeCN are strongly catalysed by general bases. The observed secondorder rate constants (kA) exhibit a curvilinear dependence on amine concentration leaving a positive intercept.
Ajay K. Jain, Anurag Kumar, Kula N. Sarma   +2 more
openaire   +1 more source

Solvation of acetone in protic and aprotic solvents and binary solvent mixtures

Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1985
The infrared spectra of dilute solutions of acetone in a range of protic and aprotic solvents have been measured in the C—O stretch region. Band maxima are shown to correlate linearly with 13C n.m.r. shifts for the carbonyl carbon and, after suitable corrections, with solvent acceptor numbers.
Martyn C. R. Symons, Graham Eaton
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Entering chloride kinetic isotope effects in protic and aprotic solvents

Journal of the American Chemical Society, 1976
Chlorine kinetic isotope effects for the reaction of ethylene oxide and chloride ion are normal (/sup 35/Cl//sup 37/Cl greater than unity) in protic solvents and in acetone and dimethylformamide (DMF) in the presence of 1 equiv of 2,6-lutidinium ion. In the presence of 0.1 equiv of this cation (and 0.9 of Li/sup +/) the isotope effect in DMF is inverse
Thomas H. Cromartie, C. Gardner Swain
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Isotropic magnetic shielding constants of retinal derivatives in aprotic and protic solvents

The Journal of Chemical Physics, 2013
We investigate the nuclear isotropic shielding constants σ(13C) and σ(17O) of isomers of retinoic acid and retinal in gas-phase and in chloroform, acetonitrile, methanol, and water solutions via Monte Carlo simulation and quantum mechanics calculations using the GIAO-B3LYP/6-311++G(2d,2p) approach.
G, Colherinhas, T L, Fonseca, M A, Castro, K, Coutinho, S, Canuto   +4 more
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DPPH assay of vegetable oils and model antioxidants in protic and aprotic solvents

Talanta, 2013
The rate of reaction of phenolic antioxidants with DPPH depends on solvent composition. The rate constants can differ by more than two orders of magnitude for the same phenolic compound. Reactions are faster in alcohols than in ethyl acetate that is used routinely for the analysis of antioxidant potential (AOP) of nonpolar samples such as vegetable ...
Tjaša, Prevc, Nataša, Segatin, Nataša Poklar, Ulrih, Blaž, Cigić   +3 more
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Photophysical Properties of Coumarin-30 Dye in Aprotic and Protic Solvents of Varying Polarities¶

Photochemistry and Photobiology, 2004
ABSTRACTExperimental results on various photophysical properties of coumarin‐30 (C30) dye, namely, Stokes' shift (Δv), fluorescence quantum yield (τf), fluorescence lifetime (τf), radiative rate constant (kf) and nonradiative rate constant (knr), as obtained using absorption and fluorescence measurements have been reported.
Sadasivam, Senthilkumar, Sukhendu, Nath, Haridas, Pal   +2 more
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Diffusion of symmetrical and spherical solutes in protic, aprotic, and hydrocarbon solvents

Journal of Solution Chemistry, 1979
The diffusion coefficients of a series of symmetrical tetraalkyltins (tetramethyltin, tetraethyltin, tetrapropyltin, tetrabutyltin, tetradodecyltin) of the gases argon, krypton, xenon, methane, and tetramethylmethane and of carbon tetrachloride and tetraethylmethane in hexane, decane, and tetradecane at 25°C have been determined using the Taylor ...
D. Fennell Evans, Toshihiro Tominaga, C. Chan   +2 more
openaire   +1 more source