摘要:

A vigorous reaction occurs between zinc filings and a solution of α,β-dibromopropionyl bromide in absolute ether. The principal organic products of the reaction are ethyl acrylate and ethyl bromide. Suggested steps in the reaction are described. The α,β-dibromopropionic acid from which the acid halides were made was obtained by oxidation of β,γ-dibromopropyl alcohol. Treatment of β-bromopropionic acid in the Hell–Volhard–Zelinsky reaction failed to accomplish bromination in the α-position, only β-bromopropionyl bromide being isolated.

ISSN:1923-4287    

DOI:10.1139/cjr50b-001

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

At temperatures of the order of 250 °C., popcorn polymer undergoes decomposition to soluble polymer. The reaction is catalyzed by peroxides present in the popcorn when the latter is formed. These peroxides may be removed by extracting the polymer with benzene. The kinetics of both the catalyzed and purely thermal solubilization reactions were investigated. The rates of both reactions are first order, the catalyzed degradation having a higher activation energy and a higher frequency factor. The rate of the thermal reaction decreases and its activation energy increases with increasing butadiene content of the polymer. A linear relation between the activation energy and the log of the frequency factor, for the decomposition of popcorn polymers of different butadiene contents, was observed. The results indicate that the rate of solubilization is determined by the activation energy of the bond scission process, and is independent of the degree of cross-linking of the polymer.

ISSN:1923-4287    

DOI:10.1139/cjr50b-002

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

The valence-state energy of the oxygen atom, calculated recently by Pauling, agrees with the lower value, 35 kcal. per mole, for the O–O bond energy. A critical review of the question is presented.

ISSN:1923-4287    

DOI:10.1139/cjr50b-003

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

The methylenedioxy-aporphine whose structure had been assigned to anonaine has been synthesized from the amide resulting from the condensation of β-3,4-methylenedioxy-phenylethylamine ando-nitrophenylacetyl chloride. The amide was cyclized to the corresponding dihydroisoquinoline, the hydriodide of which was reduced and the product transformed todl-anonaine by the Pschorr ring closure reaction. The synthetic base on methylation was converted todl-roemerine methiodide. A comparison of the properties of the derivatives obtained from anonaine and from roemerine, the structure of which is known, supplies strong evidence in favor of the validity of the structure assigned to anonaine.

ISSN:1923-4287    

DOI:10.1139/cjr50b-004

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

Comparable ortho-substituted compounds of the biphenyl, 2-phenylpyridyl, and 2,2′-bipyridyl type have been synthesized and resolved, and the resistance to racemization determined. The results are as would have been predicted on geometrical considerations only, the compounds containing nitrogen atoms in the rings not behaving in any abnormal manner.

ISSN:1923-4287    

DOI:10.1139/cjr50b-005

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

not available

ISSN:1923-4287    

DOI:10.1139/cjr50b-006

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

not available

ISSN:1923-4287    

DOI:10.1139/cjr50b-007

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

not available

ISSN:1923-4287    

DOI:10.1139/cjr50b-008

出版商:NRC Research Press    

年代:1950

数据来源: NRC