摘要:

The reactions of H and D atoms, produced by the discharge method, with benzene, four cycloalkanes, and the corresponding normal paraffins have been investigated at room temperature. Methane is the major product of each reaction. Collision yields have been calculated on the basis of hydrocarbon disappearance and exchange. Of the cycloalkanes, cyclopropane is the most inert with cyclopentane the most reactive. Cyclopropane and cyclobutane do not exchange with D atoms but benzene, cyclopentane, and cyclohexane undergo considerable exchange. In the case of the normal paraffins the degree of exchange increases with increasing molecular weight.It is concluded that the initial reactionis responsible for the products formed in the reactions but other primary processes may be responsible for the exchange of these hydrocarbons.

ISSN:0008-4042    

DOI:10.1139/v51-001

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Thermopsine, an isomer of anagyrine, is associated with the latter in nature, but differs from it in chemical reactivity. Evidence, both chemical and from the infrared spectra, indicates that the molecule of thermopsine contains an α-pyridone ring, and possesses a structure closely related to that of anagyrine. Catalytic reduction of the alkaloid yields α-isosparteine, a stereoisomer of sparteine. It is therefore suggested that thermopsine is a stereoisomer of anagyrine, to which it bears the same relationship as α-isosparteine to sparteine. The stereochemistry of these bases is discussed.

ISSN:0008-4042    

DOI:10.1139/v51-002

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The species ofLupinusunder investigation has been found to contain five alkaloids:l-α-isosparteine,d-α-isolupanine,d-thermopsine,l-sparteine andd-lupanine. The first three had not heretofore been reported as occurring in nature. Bothd-α-isolupanine andd-thermopsine can be converted by hydrogenation intol-α-isosparteine and are both structurally related to this stereoisomer of sparteine.

ISSN:0008-4042    

DOI:10.1139/v51-003

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Potassium formate labeled with C14was fed to sprouting barley, and choline and hordenine (N-dimethyltyramine) were isolated from the roots. Both of these substances bore the labeled carbon largely, if not entirely, in the methyl groups, as shown by means of degradation experiments. This indicates that the N-methyl groups of these compounds originate from formate ions.

ISSN:0008-4042    

DOI:10.1139/v51-004

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The infrared absorption spectrum of gelsemine indicates the presence of a carbonyl group. Reduction of the alkaloid with lithium aluminum hydride converts the carbonyl not to a secondary alcohol, but to a methylene group, thus indicating that the carbonyl is present in a lactamic grouping. The reduced base shows the properties of a substituted aniline. Since gelsemine has been shown to yield 3-ethylindole on dehydrogenation with selenium and since the N-atom involved in the lactamic group cannot be the strongly basic nitrogen, gelsemine must contain an oxindole grouping. Furthermore, 3-monosubstituted oxindoles are converted by lithium aluminum hydride to 3-substituted indoles, whereas gelsemine under the same conditions gives rise to a dihydroindole. Therefore, the alkaloid must contain a 3, 3-disubstituted oxindole grouping.

ISSN:0008-4042    

DOI:10.1139/v51-005

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

A study of the reduction of nitroglycerin with titanous sulphate has been carried out. The results indicate that for each mole of nitroglycerin reduced, 18 moles of titanous ion are oxidized, two moles of ammonia, one-half mole of nitrogen trioxide, and one mole of glycerol are formed. It has been shown that the reduction takes place first to 1,3-dinitro-2-nitrosoglycerin which, after hydrolysis to 1, 3-dinitroglycerin, is reduced to glycerol with the probable intermediate formation of 1, 3-dinitrosoglycerin. The determination of nitroglycerin by the Shankster and Wilde method is more accurate when 70% acetic acid is substituted for methanol as the solvent for nitroglycerin.

ISSN:0008-4042    

DOI:10.1139/v51-006

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Benzoyl peroxide and cumene hydroperoxide (CHP) are reduced at the anodically polarized dropping mercury electrode, the former at about +0.3 volt vs. S.C.E., and the latter at +0.1 v. Their half-wave potentials as well as that of the two reduction steps of dissolved oxygen are gradually shifted towards more negative values with increasing concentration of organic peroxides. The polarographic method is suitable for determining these peroxides in concentrations up to 2 × 10−3 mole per liter. Dissolved oxygen does not interfere seriously with the analyses.

ISSN:0008-4042    

DOI:10.1139/v51-007

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

Lithium, sodium, and caesium iodides are highly ionized in acetonitrile solution and have practically the same rates and activation energies (18 kcal. per mole) for their exchange reactions withn-butyl iodide in this solvent. There seems little doubt, therefore, that these exchange reactions occur between the organic iodide and iodide ion derived from the inorganic salt. Zinc and cadmium iodides, and iodine, are only slightly ionized in acetonitrile and exchange withn-butyl iodide with rates that are widely different from one another and from the rate of iodide ion exchange. The activation energies are 21.9, 20.6, and 17.5 kcal. per mole respectively. It is concluded that these exchange reactions involve predominantly complex ions.

ISSN:0008-4042    

DOI:10.1139/v51-008

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

The Darapsky degradation, by which a carbethoxy group is replaced by an amino group, has been applied successfully to substituted cyanoacetic esters for the preparation of 10 amino acids. The esters were formed by condensation of ethyl cyanoacetate with alkyl or arylalkyl halides. The hydrazides were obtained by treatment of the esters with hydrazine hydrate and identified by their anisal derivatives. Diazotization of the hydrazides gave rise to azides. These were transformed into carbethoxyaminonitriles by refluxing with absolute ethanol. The urethanes, on acid hydrolysis, yielded the amino acids. The following amino acids were synthesized: DL-β-methylleucine, DL-α-amino-β-methylisoheptanoic acid, DL-α-amino-β-cyclohexylpropionic acid, DL-C-o-methylcyclohexylglycine, DL-C-m-methylcyclohexylglycine, DL-C-p-methylcyclohexylglycine, DL-C-o-xylylglycine, DL-C-m-xylylglycine, DL-C-p-xylylglycine, DL-p-ethylalanine.

ISSN:0008-4042    

DOI:10.1139/v51-009

出版商:NRC Research Press    

年代:1951

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v51-010

出版商:NRC Research Press    

年代:1951

数据来源: NRC