摘要:

Octalupine has been shown to be identical with hydroxylupanine by means of a comparison of the physical properties of the bases and corresponding derivatives and also by a direct comparison of the infrared absorption spectra of both alkaloids.

ISSN:0008-4042    

DOI:10.1139/v51-082

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Ammonium nitrate can be withheld from the Bachmann reaction at 35°C. for several hours without reducing the yield of RDX below approximately 50% of the normal value for the given amount of ammonium nitrate added. The rates of formation of RDX, on the addition of ammonium nitrate from 15 min. to five hours after the reaction has started in its absence, are approximately the same and are approximately one-half that when ammonium nitrate is present initially. A low temperature analysis for hexamine in the Bachmann mixture, by precipitating hexamine as the styphnate, indicates that hexamine disappears from the reaction mixture within five seconds at 35°C, either in the presence or absence of ammonium nitrate.

ISSN:0008-4042    

DOI:10.1139/v51-083

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Measurements of the rates of alkaline hydrolysis of cyclotrimethylenetrinitramine (RDX) and cyclotetramethylenetetranitramine (HMX) in aqueous acetone show these two reactions to involve consecutive steps, the first of which is second order and rate controlling. Activation energies were estimated as 14 and 25 kcal. respectively. By establishing calibration curves, and controlling temperature, alkali concentration relative to concentration of explosive, and reaction time, the differential hydrolysis permits analysis of the HMX content of RDX(B) with an error of approximately ±0.2% HMX.

ISSN:0008-4042    

DOI:10.1139/v51-084

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Wheat plants were harvested approximately every two weeks after emergence from the soil. Determination of the lignin content by the 72% sulphuric acid method showed a rapid increase between the period 45–70 days from seeding, and there was a corresponding increase in the yield of vanillin and syringaldehyde, obtained by alkaline nitrobenzene oxidation. Thep-hydroxybenzaldehyde yield remained low at all times and seemed to be derived from a different system. It is suggested that the source of this aldehyde is not the lignin, but the tyrosine associated with the protein. The ratios of vanillin to syringaldehyde did not remain constant from plants of different ages, the percentage of syringaldehyde being lower than vanillin in the young plants and higher in those which were more mature. This is qualitatively in agreement with an increase in the methoxyl content of the lignin.When the yield of aldehydes from mature plants is taken as the criterion for the amount of lignin present, the youngest plants have a lignin content of about 0.13%, a value much lower than other bases for calculation would indicate.Oxidation of the whole plant and of the plant which had been extracted with alcohol–benzene, water, and 1% hydrochloric acid, gave similar percentages of aldehydes, owing partly to the removal of aldehyde-producing substances and partly to the degradation of the lignin during the extraction process. Oxidation of the extracts gave no trace of aldehyde in the hydrochloric acid extract, a trace in the water extract, and appreciable percentages in the alcohol–benzene extract. This latter extract consisted of two portions, a red water soluble, alcohol–benzene insoluble fraction and the main alcohol–benzene soluble fraction. The former gave rise to vanillin andp-hydroxybenzaldehyde on oxidation, the amount being a maximum at the first harvest and decreasing to zero after lignification had occurred. The latter, that is, the alcohol–benzene soluble extract, gave rise to syringaldehyde as well as the others, the amounts being low at first and increasing during lignification in the same way as the main body of the plant. It is believed that the alcohol–benzene removes a soluble portion of the lignin since the relative proportions of the aldehydes are very similar to those obtained from lignin itself.

ISSN:0008-4042    

DOI:10.1139/v51-085

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The ultraviolet absorption spectra of a number of derivatives of nitroguanidine were determined. An analysis of the effects of substituents on the absorption spectrum of nitroguanidine has led to the conclusion that it exists as a resonance hybrid of several structures including (a) and (b).The bearing of these structures on the nomenclature of nitroguanidine and its derivatives is discussed. Also the structures of some of the derivatives of nitroguanidine have been interpreted from their absorption spectra.

ISSN:0008-4042    

DOI:10.1139/v51-086

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

A partition chromatographic technique was established for the estimation of the acetic,n-caproic,L-β-hydroxy-n-caproic, andL-β-hydroxy-n-caprylic acids which are liberated on the hydrolysis of ustilagic acid. The free carboxyl group of ustilagic acid was shown to be derived from the ustilic acid residue. Since fractional precipitation of ustilagic acid did not alter the original composition, it was concluded that ustilagic acid consists of 65–70% of a monoacetyl-mono-L-β-hydroxy-n-caproylglucoustilic acid and 25–30% of a monoacetyl-mono-L-β-hydroxy-n-caprylylglucoustilic acid.

ISSN:0008-4042    

DOI:10.1139/v51-087

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The evidence presented by Vroom and Winkler that 3,5-dinitro-3,5-diazapiperidinium nitrate is an intermediate compound in the conversion of hexamine dinitrate to Cyclonite has been vitiated by the demonstration that it cannot survive the reaction conditions in which it supposedly was formed. Presumably the formation of 3,5-dinitropiperadinium nitrate occurs during dilution by decomposition of 1-dimethylolaminomethyl-3,5-dinitro-1,3,5-triazacyclohexane and/or 1-methylol-3,5-dinitro-1,3,5-triazacyclohexane. Evidence favoring the latter as the stable intermediate is afforded by demonstration that dimethylolnitramide also is present. When the cold nitrolysis mixture is treated with acetic anhydride rather than water the intermediate is esterified and nitrolyzed to 1-acetoxy-7-nitroxy-2,4,6-trinitro-2,4,6-triazaheptane and 1,7-diacetoxy-2, 4, 6- tri-nitro-2,4,6-triazaheptane.

ISSN:0008-4042    

DOI:10.1139/v51-088

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Conductivity and density data have been obtained for the system silver chloride – silver nitrate. The Arrhenius activation energy for electrical migration in molten silver chloride is constant at 1280 cal. mole−1from 460 to 530 °C.; for silver nitrate there is a variation from 3300 cal. mole−1at 220 ° to 2700 at 320 °C., which indicates a diminution of structural forces in molten silver nitrate with increase in temperature. The activation energy for binary melts of the two salts at 320 °C. is constant at 2700 cal. mole−1from 0 to 20 mole % silver chloride; Frenkel's simple equation for the dependence of the activation energy on composition is not supported by this work.

ISSN:0008-4042    

DOI:10.1139/v51-089

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Dioxane reacted slowly at room temperature with anhydrous, bromine free hydrogen bromide to form 2, 2′-dibromodiethyl ether as a principal product. The 2, 2′-dibromodiethyl ether was characterized by comparison with a known sample, analysis, molecular weight determination, and by conversion to divinyl ether which was subsequently brominated to yield 1, 1′, 2, 2′-tetrabromodiethyl ether. When refluxed with constant boiling hydrobromic acid 2, 2′-dibromodiethyl ether was partially converted to ethylene dibromide. An intermediate compound in the formation of 2, 2′-dibromodiethyl ether from dioxane and hydrogen bromide was isolated by solvent extraction using petroleum ether. Its properties indicated that it was probably an oxonium salt.

ISSN:0008-4042    

DOI:10.1139/v51-090

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The exchange of iodine between hydrogen iodide andn-butyl iodide has been studied in several organic solvents. In solvents of high dielectric constant (methanol, ethanol,n-butanol), exchange occurred by reaction of iodide ions with butyl iodide. In solvents of low dielectric constant (n-hexanol,n-dodecanol, acetic acid), it appeared that exchange also occurred between butyl iodide and the associated IHI−triple ion. Orders of magnitude of the individual specific rate constants have been calculated, using approximate values for the dissociation constants of hydrogen iodide. The rate constant – dielectric constant relation developed by Laidler and Eyring for ion – neutral molecule reactions appears to hold for exchange in homologous solvents, but does not seem to represent the effect of nonhomologous solvents. This discrepancy and the small differences observed in activation energies for the various exchanges may be due to solvation effects.

ISSN:0008-4042    

DOI:10.1139/v51-091

出版商:NRC Research Press    

年代:1951

数据来源: NRC