摘要:

Protonation of N,N-dimethylnitrosoamine has been investigated by dissolving the nitrosoamine in different acids and recording the proton magnetic resonance spectra of these solutions. Concentrated sulfuric acid, sulfuric acid monohydrate, perchloric acid (72%), trifluoroacetic acid, and fluorosulfuric acid have been used in this study. Only in fluorosulfuric acid near 0 °C and lower was a new signal observed for the protonated nitrosoamine molecule. Integration of the peaks has shown that only one proton is captured by the nitrosoamine. The following structure is suggested for the protonated nitrosoamine.The n.m.r. spectra of fluorosulfuric acid solutions of N,N-diethylnitrosoamine and N-nitrosopiperidine also show separate signals for the captured proton.The n.m.r. spectrum of an equimolar solution of N,N-dimethylnitrosoamine, N,N-dimethylformamide, and trifluoroacetic acid in 2-nitropropane indicates that N,N-dimethylnitrosoamine is a weaker base.

ISSN:0008-4042    

DOI:10.1139/v66-019

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The effect of extraction of uranyl nitrate on certain neutral organophosphorus compounds has been observed by nuclear magnetic resonance (n.m.r.) spectroscopy. Proton and phosphorus chemical shifts have been measured for the complexed and uncomplexed material. The effect of complexation on proton–proton and proton–phosphorus coupling constants has been noted.

ISSN:0008-4042    

DOI:10.1139/v66-020

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The rates of reaction of various phenols with the 2,4,6-trinitrobenzyl anion in the solvent ethanol have been determined by a spectrophotometric method. The rate constants at −40 °C are related to the dissociation constants of the phenols in water at 25 °C and the value of α in the Brönsted relation is 0.84 ± 0.07; α drops to 0.44 ± 0.05 if the results for the substituted acetic acids (1) are included. The rate constants for the phenols are also correlated by the Hammett relationship, the ρ value at −40 °C being 1.82 ± 0.2. The activation energies range from 9.4 to 10.9 kcal/mole.The rate of reaction of trinitrobenzyl anion with 3-methylphenol at −30 °C is reduced by a factor of 12 if the phenol is deuterated at the OH group and the solvent is deuteroethanol. The large isotope effect confirms that the rate-determining step involves proton transfer from the OH group of the phenol. Substitution of lithium or potassium cations for the sodium cation does not affect the rate constant at −10 °C.In the reaction with 3-methylphenol, a measurable concentration of trinitrobenzyl anion remains at equilibrium and the equilibrium constant for the reaction is 1.3 ± 0.2 at 25 °C. The heat and entropy changes are approximately −6.5 kcal/mole and −21 e.u./mole respectively.

ISSN:0008-4042    

DOI:10.1139/v66-021

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Infrared spectra of metal-free phthalocyanine, chlorinated and unchlorinated copper phthalocyanines, and three new metal derivatives of phthalocyanine: MoPc, Na2Pc, and AlOH—Pc (Pc = C32H16N8), have been recorded. Assignments have been suggested for many of the peaks in the infrared spectra of the phthalocyanines.

ISSN:0008-4042    

DOI:10.1139/v66-022

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

An exploratory research program investigated the possibility of preparing metal nitrides by electrically exploding metal wires and foils in an atmsophere of (a) nitrogen, (b) ammonia, or (c) nitrogen and hydrogen. The explosions were carried out in an enclosed stainless steel pressure vessel. In a few cases, the wire was exploded while covered with liquid nitrogen in a stainless steel container maintained at liquid nitrogen temperatures.The samples were analyzed using a modified Kjeldahl method for nitrogen. Greater yields of nitrides were obtained when a greater charge was given the oil-filled condensers used to supply the current, and when the pressure of gas surrounding the wire was increased. Yields as high as 50% were obtained in some cases. Clearly defined nitrides were obtained with magnesium, titanium, zirconium, tantalum, zinc, and aluminium. The metals iron, rhodium, platinum, copper, and cadmium did not appear to form stable nitrides under the experimental conditions.A brief discussion of a mechanism by which a wire may explode is given.

ISSN:0008-4042    

DOI:10.1139/v66-023

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The addition of CO is found to increase the rate of the mercury-photosensitized decomposition of certain compounds (ethylene, acetone, anisole) by a factor in excess of 2.5, but does not affect the rate with paraffin hydrocarbons. The addition of N2, known to quench Hg(3P1) to the metastable Hg(3P0) state, does not produce an increase in rate. The results are discussed with reference to a possible HgCO* complex which contains most of the original excitation energy of Hg(3Pi) atom.

ISSN:0008-4042    

DOI:10.1139/v66-024

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

The high resolution proton magnetic resonance spectra of five samples of poly(methyl methacrylate) in chloroform solution have been measured with 100 Mc/s equipment. The widths of the absorption lines arising from the protons of the α-methyl and the methoxyl groups have been compared. The widths are greater when the polymer is predominantly syndiotactic than when it is predominantly isotactic. It is concluded that isotactic samples have the more extended conformation in chloroform solution. An analogy with dilute solution viscosity measurements is outlined in support of this conclusion. Differences between the widths of the lines of the methylene protons in a completely isotactic poly(methyl methacrylate) sample are attributed to long range spin coupling.

ISSN:0008-4042    

DOI:10.1139/v66-025

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

A method is described to calculate the equilibrium configuration of any number of identical particles restricted to a spherical surface and interacting with forces derivable from an inter-particle potential of the formr−n. It is shown that distributions of symmetryC2are expected for seven particles whennis small. In certain cases, the model can be used to explain the shape of molecules of the type MXm. The importance of directed valence in these molecules is considered and the structure of IF7discussed.

ISSN:0008-4042    

DOI:10.1139/v66-026

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

Oxidation studies from 425 to 600 °C of porous carbons obtained from the pyrolytic decomposition of pure polyvinylidene chloride have been carried out in static oxygen systems. Measurements of weight change were made by means of a sensitive thermal microbalance. Empirical activation energies for the oxidation reaction were determined to be approximately 1 eV in magnitude, and comparison is made with previously published results for graphite. Carbon samples obtained from polymers compressed at different molding pressures showed somewhat different temperature and pressure rate dependence. An unusual pressure dependence was observed for the rate of reaction, and a tentative explanation is offered.

ISSN:0008-4042    

DOI:10.1139/v66-027

出版商:NRC Research Press    

年代:1966

数据来源: NRC

摘要:

With perfluoroazoethane as a photolytic source of C2F5radicals, the hydrogen abstraction reactions of C2F5with deuterium, ethane, cyclohexane, acetone, and trifluoroacetaldehyde have been studied, and the Arrhenius parameters derived. The H-atom abstraction reactions of the three perfluoroalkyl radicals, CF3, C2F5, and C3F7, are discussed.

ISSN:0008-4042    

DOI:10.1139/v66-028

出版商:NRC Research Press    

年代:1966

数据来源: NRC