Showing papers on "Acetonitrile published in 1970"

Yield of Ions and Excited States Produced in the Radiolysis of Polar Organic Liquids

Abstract: The yield of ions and triplet excited states produced in the radiolysis of polar protic and aprotic organic liquids was studied using the technique of pulse radiolysis. Anthracene and naphthalene were used to determine the yield of electrons and triplet excited states, respectively. Taking emax = 9.9 × 103 M−1·cm−1 for (anthracene)−, the yields of anthracene anions, considered to represent the yield of free ions produced, were found to vary from G values 0.1 to ∼ 2.6 for the 20 organic liquids examined. The yields of triplet states were found to depend, in a number of cases, upon the presence of electron scavengers in the liquids. The liquids studied include p‐dioxane, MTHF, pyridine, aliphatic alcohols, acetone, benzonitrile,acetonitrile, dimethylsulfoxide, 1,2‐propanediol carbonate, dimethylformamide, dimethylacetamide, and N‐methylpropionamide. The static dielectric constant values of these liquids ranged from ∼ 2.0 to 165.0. These results are evaluated and discussed, and the potential interest of some...

Carbon-13 Nuclear Magnetic Resonance Spectroscopy. Solvent Effects on Chemical Shifts

Abstract: The ^(13)C chemical shift of chloroform has been measured in a variety of solvents Relative to dilute solution in cyclohexane, all of the solvents studied resulted in downfield shifts which, with the exceptions of benzene and acetonitrile, correlate linearly (r = 0982) with the changes in proton shifts in the same solvents The results, taken with the variation of the ^(13)C-H coupling constant with solvent, suggest that the solvent effects arise from changes in the average distance of the bonding electrons in the chloroform C-H bond as the result of intermolecular association Contributions from the anisotropy of benzene and acetonitrile indicate that measurements of the chemical shift of more than one nucleus in the same molecule may allow detection and estimation of neighbor anisotropy contributions to chemical shifts

Diffusion Coefficients in Propylene Carbonate, Dimethyl Formamide, Acetonitrile, and Methyl Formate

Abstract: Propylene carbonate, dimethyl formamide, acetonitrile and methyl formate diffusion coefficients measurement for estimating nonaqueous Li batteries transport limitations

Acetonitrilecarbonyl and acetonitrilenitrosyl metal cations from the reactions of the nitrosonium ion, NO+, with transition-metal organometallics in acetonitrile

Abstract: The reactions of NOPF6 in acetonitrile with (π-PhMe)Cr(CO)3 and M2(CO)10(M = Mn and Re) lead to the formation of [Cr(NO)2(MeCN)4][PF6]2 and [M(CO)5(MeCN)][PF6], respectively, which are valuable new organometallic reagents as exemplified by a variety of reactions.

Dielectric relaxation in the mixtures of some nitriles

Abstract: Dielectric constants and losses have been measured at wavelengths of 3 × 104, 10.0, 3.22, 1.96, and 1.25 cm at 30°C for pure acetonitrile, pure propionitrile, five mixtures of acetonitrile and benzonitrile and three mixtures of propionitrile and benzonitrile. A single relaxation time of 3.3 × 10–12 s has been obtained for pure acetonitrile, whereas the dielectric data of pure propionitrile indicate an unsymmetrical distribution of relaxation times in good agreement with the Davidson-Cole representation. The dielectric data of the binary mixtures of acetonitrile and benzonitrile have been analyzed in terms of two partly superimposed Deby e regions, whereas that of propionitrile and benzonitrile have been interpreted in terms of three partly overlapping Debye regions.

Preparation of N‐Alkylacetamides by the Anodic Oxidation of Carboxylic Acid Salts

Abstract: The possibility of preparing N‐alkylacetamides by the electrolytic oxidation of carboxylate ions at a carbon anode in the presence of acetonitrile has been investigated. A yield of substituted acetamide of about 50% was obtained with potassium valerate, but it gradually dropped to zero in favor of the Kolbe coupled product in going from potassium octanoate to potassium laurate. An explanation of this effect involving specific orientation of the adsorbed long chain carboxylates on the electrode surface is included. Products derived from intermediate carbonium ions were found, and a mechanism for their formation is proposed.

The synthesis and some reactions of bis(acetonitrile)(diene)-rhodium and -iridium tetrafluoroborate

Abstract: The synthetic and catalytic properties of the complexes [M(diene)2]+BF4–, [M(diene)(CH3CN)2]+BF4–, and [M(diene)L2]+BF4–(M = Rh or Ir, L = phosphines or bipyridyl) are discussed.

Stepwise synthesis of oligopeptides with N-carboxy alpha-amino acid anhydrides.

Abstract: Oligopeptides were synthesized in high yields by the controlled coupling reaction of N-carboxy α-amino acid anhydrides (NCA's) with amino acid and peptide sodium salts in the heterogeneous reaction medium of acetonitrile–water which contained sodium carbonate. In this solvent, it could be considered that the reaction could occur at the interface of acetonitrile and aqueous layers, and that NCA's could be protected by the organic layer from side reactions such as hydrolysis and polymerization. The careful control of reaction conditions such as pH of the solution was not necessary when the heterogeneous mixed solvent was used. Sodium carbonate which had not been used for a reaction of this kind could be satisfactorily used for stabilizing the carbamate intermediates in the aqueous layer of the heterogeneous reaction medium.

Infrared spectra of acetonitrile sorbed on porous glass

Abstract: Infrared spectra were recorded of acetonitrile sorbed on highly degassed porous glass as well as on silica and B-, Al-, and Zr-impregnated porous glass and silica. Most of the acetonitrile was weak...

The crystal and molecular structure of some derivatives of NN′-ethylenebis(salicylaldehydeiminato)cobalt(III)

Abstract: The crystal and molecular structure of the Co(salen) complexes with acetonitrile, pyridine, acetone, and methoxyl as further ligands [cyanomethyleneCo-(salen) with methanol, methoxy-Co(salen) with pyridine and methanol, acetonylCo(salen) with methanol] have been determined by X-ray structural analysis.