Photoreduction of Pyruvic Acid by Isopropyl Alcohol and t-Butyl Alcohol. A Kinetic Study1

1966 ◽  
Vol 88 (12) ◽  
pp. 2766-2768 ◽  
Author(s):  
Douglas S. Kendall ◽  
Peter A. Leermakers
Keyword(s):  
Pyruvic Acid ◽  
Isopropyl Alcohol ◽  
Butyl Alcohol

Solubility and Thermodynamic Transfer Functions of Cesium Dianilinetetraisothiocyanatochromate(III)

1998 ◽  
Vol 63 (3) ◽  
pp. 293-298
Author(s):  
Vladislav Holba
Keyword(s):  
Experimental Data ◽  
Isopropyl Alcohol ◽  
Transfer Functions ◽  
Butyl Alcohol ◽  
Aqueous Methanol ◽  
Gibbs Energies ◽  
Gibbs Energy Of Transfer ◽  
Energy Of Transfer ◽  
The Given ◽  
Reference Electrolyte

The solubilities of cesium dianilinetetraisothiocyanatochromate(III) in water as well as in aqueous methanol, isopropyl alcohol, tert-butyl alcohol and acetonitrile were measured as a function of temperature and solvent composition. The Gibbs energies, enthalpies and entropies of transfer of the salt from water to the given solvents have been evaluated from experimental data. The contribution of [Cr(C6H5NH2)2(NCS)4]- ion to the Gibbs energy of transfer of the investigated salt has been calculated using the tetraphenylarsonium tetraphenylborate (TATB) reference electrolyte assumption.

Aflatoxins M1 and M2 and Parasiticol: Thin Layer Chromatography and Physical and Chemical Properties

1972 ◽  
Vol 55 (4) ◽  
pp. 762-767
Author(s):  
R D Stubblefield ◽  
O L Shotwell ◽  
G M Shannon
Keyword(s):  
Acetic Anhydride ◽  
Isopropyl Alcohol ◽  
Chemical Properties ◽  
Butyl Alcohol ◽  
Amyl Alcohol ◽  
Good Resolution ◽  
Water Addition ◽  
Maximum Resolution ◽  
Tlc Plates ◽  
Derivatives Of

Abstract A survey of known anatoxin solvent systems for resolution of aflatoxins M1 and M2 on TLC plates revealed that the best system for determining aflatoxins B1, B2, G1, G2, M1, and M2 is isopropyl alcohol-acetone-chloroform (5 + 10 + 85). Substitution of various alcohols for isopropyl alcohol in this system demonstrated that maximum resolution of M1 and M2 was achieved with n-amyl alcohol-acetone-chloroform (10 + 10 + 80); however, B1, B2, G1, and G2 migrated with the solvent front. When alcohol-chloroform (5 + 95) mixtures were investigated, n-propyl, n-butyl, and tert-butyl alcohol + chloroform resolved M1 and M2 best but did not separate B1, B2, G1, or G2. Molar absorptivities of both M1 and M2 were determined in methanol, chloroform, acetonitrile, and acetonitrile-benzene (2 + 98). Relative fluorescent intensities of aflatoxins B1, M1, and M2 were compared on both developed and undeveloped TLC plates. Fluorescent intensities of B1 and M1 on silica gel were nearly equal, and the intensity of M2 was 1.4–1.5 times that of the other 2 aflatoxins. Water adducts of anatoxin M1 and parasiticol were prepared. The diacetate adducts of parasiticol were formed by treatment with acetic anhydride and concentrated HC1. Monoacetyl derivatives of M1, M2, and parasiticol were obtained by treatment with pyridine and acetic anhydride. Good resolution of the water-addition derivatives of B1, G1, parasiticol, and Mi on TLC plates was achieved with isopropyl alcoholacetone-chloroform (5 + 10 + 85).

A new method for the determination of the relative acidities of alcohols in alcoholic solutions. The nucleophilicities and competitive reactivities of alkoxides and phenoxides

1979 ◽  
Vol 57 (20) ◽  
pp. 2747-2754 ◽  
Author(s):  
Wilkins Reeve ◽  
Charles M. Erikson ◽  
Patrick F. Aluotto
Keyword(s):  
Isopropyl Alcohol ◽  
Butyl Alcohol ◽  
New Method ◽  
Butyl Bromide ◽  
Tert Butyl ◽  
Ether Mixture ◽  
Tert Butyl Alcohol ◽  
Relative Nucleophilicity ◽  
Semiquantitative Method

A new semiquantitative method has been developed for measuring the relative acidities of methanol, ethanol, isopropyl alcohol, and tert-butyl alcohol in mixed hydroxylic solvents. A solution of the alkoxides of two alcohols in an excess of the two alcohols is allowed to react with n-butyl bromide to form a mixture of two ethers. The composition of the ether mixture is a measure of the "competitive reactivity" of thetwo alkoxides. This can be measured directly, and in theory can be factored into two components: the relative nucleophilicity and the relative basicity of the two alkoxides. Relative nucleophilicities are determined by using solutions in which phenol is one component. Knowing the competitive reactivities and nucleophilicities, the relative acidities of methanol, ethanol, isopropyl alcohol, and tert-butyl alcohol in alcoholic media are shown to be 4.4, 1.0, 0.24, and 0.21, respectively. The relative nucleophilicities of hydroxide, methoxide, ethoxide, isopropoxide, tert-butoxide, phenoxide, and m-cresoxide are 0.08, 0.82, 1.0, 0.4, 0.04, 0.46, and 0.57 respectively.

The transmission of polar effects. Part X. The esterification with diazodiphenyl-methane and the ionization of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids

1969 ◽  
Vol 47 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Keith Bowden ◽  
D. C. Parkin
Keyword(s):  
Free Energy ◽  
Ethyl Acetate ◽  
Field Effect ◽  
Isopropyl Alcohol ◽  
Substituent Effects ◽  
Butyl Alcohol ◽  
Rate Coefficients ◽  
Linear Free Energy ◽  
Energy Relations ◽  
Substituted 1

The rate coefficients for the reaction with diazodiphenylmethane in methanol, ethanol, isopropyl alcohol, t-butyl alcohol, 2-methoxyethanol, 2-n-butoxyethanol, and ethyl acetate at 30° and the pKa values in 80% 2-n-butoxyethanol–water of a series of 9-substituted 10-anthroic and 8-substituted 1-naphthoic acids have been determined. The effect of substitution has been analyzed by linear free energy relations. The variation in the susceptibilities of the systems to polar substituent effects with the medium are examined. The occurrence of reversed dipolar substituent effects in the reactions of the 1,8-naphthoic acids is detected. The implications of the results for the inductive and field effect models for the transmission of polar effects are discussed.

scholarly journals In VirtoAntioxidant Activities of New 4,5-Dihydro-1H,2,4-triazol-5-ones having Thiophene Ring with their Acidic Properties

2011 ◽  
Vol 8 (4) ◽  
pp. 1734-1746 ◽  
Author(s):  
H. Yuksek ◽  
F. Islamoglu ◽  
O. Gursoy Kol ◽  
S. Bahceci ◽  
M. Bekar ◽  
...  
Keyword(s):  
Isopropyl Alcohol ◽  
Antioxidant Activities ◽  
Thiophene Ring ◽  
Butyl Alcohol ◽  
Dimethyl Formamide ◽  
Acidic Properties ◽  
Alkyl Aryl ◽  
Neutralization Potential ◽  
New Compounds ◽  
Derivatives Of

Seven new 3-alkyl(aryl)-4-(2-thienymethylenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones(2)were synthesized by the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones(1)with thiophene-2-carbaldehyde. In addition,N-acetyl derivatives of compounds2d-2gwere also prepared. The structures of eleven new compounds synthesized were determined by elemental analysis as well as IR, NMR and UV spectral data. In addition, compounds2a-gand3a,3b,3d-fwere also screened for their antioxidant activities and2a-gwere potentiometrically titrated with tetrabutylammonium hydroxide (TBAH) in four nonaqueous solvents (isopropyl alcohol,t-butyl alcohol, acetonitrile andN,N-dimethyl formamide). Also half-neutralization potential values and the corresponding pKa values were determined in all cases.

The transmission of polar effects. Part V. The kinetics of esterification with diazodiphenylmethane and the ionization of substituted acetic and propionic acids in several solvents

1968 ◽  
Vol 46 (18) ◽  
pp. 2929-2940 ◽  
Author(s):  
Keith Bowden ◽  
M. Hardy ◽  
D. C. Parkin
Keyword(s):  
Isopropyl Alcohol ◽  
Butyl Alcohol ◽  
Rate Coefficients ◽  
Esterification Reaction ◽  
Linear Free Energy ◽  
Ionization Reaction ◽  
Reaction Constants ◽  
Polar Substituents ◽  
Energy Relations ◽  
Kinetics Of

The rate coefficients for the reaction with diazodiphenylmethane in methanol, ethanol, isopropyl alcohol,t-butyl alcohol, 2-methoxyethanol, 2-n-butoxyethanol, dimethyl sulfoxide, ethyl acetate, and toluene at 30° and the pKa values in water, 50% ethanol–water, and 80% 2-methoxyethanol–water of 18 substituted acetic and propionic acids have been determined. A further 14 acids have been studied to a more limited extent. The effect of substitution has been estimated by linear free energy relations. The reaction constants for the ionization reaction are almost independent of the medium. This is interpreted as being due to the field effect of the proximate polar substituents passing through the molecular cavity almost alone. The occurrence of steric inhibition of solvation causing acid weakening for bulky multi-substitution is confirmed. The reaction constants for the esterification reaction are affected by the solvent. This is attributed to dependence on solvation of the transition state.

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