| 1. |
THE SYNTHESIS OF POSSIBLE DEGRADATION PRODUCTS OF METATHEBAINONE. II. |
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Canadian Journal of Research,
Volume 22b,
Issue 4,
1944,
Page 109-114
H. L. Holmes,
L. W. Trevoy,
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摘要:
The poor yield of β-(3,4-dimethoxybenzoyl)-propionic acid obtained from the condensation of equimolar quantities of veratrole and succinic anhydride by two moles of aluminium chloride is due to the demethylation of the C4-methoxyl group. The phenolic acid has been isolated and its structure established by degradation to 3-methoxy-4-ethoxybenzoic acid. The yield of the dimethoxy-acid has been improved to 83% by modifying the usual procedure for this reaction.
ISSN:1923-4287
DOI:10.1139/cjr44b-013
出版商:NRC Research Press
年代:1944
数据来源: NRC
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| 2. |
SOME DERIVATIVES OF DIALKOXY-PHTHALIDES |
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Canadian Journal of Research,
Volume 22b,
Issue 4,
1944,
Page 115-124
Richard H. F. Manske,
Archie E. Ledingham,
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摘要:
Treatment of certain dialkoxy-benzoic acids was found to yield dialkoxy-phthalides containing a chloromethyl group. The constitutions of a number of these compounds have been elucidated by unambiguous syntheses.Inter alia, it was observed that the Fries rearrangement of 4-acetoxy-3-methoxy-toluene yielded exclusively am-hydroxy-acetophenone. This appears to be the only recorded case of an exclusive meta-rearrangement. Several intermediate aldehydes and some compounds derived from them are described.
ISSN:1923-4287
DOI:10.1139/cjr44b-014
出版商:NRC Research Press
年代:1944
数据来源: NRC
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| 3. |
NOTE ON A THERMOSTATICALLY CONTROLLED MICROSCOPE HOT STAGE |
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Canadian Journal of Research,
Volume 22b,
Issue 4,
1944,
Page 125-126
I. E. Puddington,
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摘要:
A microscope hot stage, capable of maintaining any desired temperature to within ±0.1 °C. in the range from room temperature to 300 °C, is described.
ISSN:1923-4287
DOI:10.1139/cjr44b-015
出版商:NRC Research Press
年代:1944
数据来源: NRC
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| 4. |
THE SEPARATION OF THE OXYGEN ISOTOPES BY THE DISTILLATION OF WATER |
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Canadian Journal of Research,
Volume 22b,
Issue 4,
1944,
Page 127-136
H. G. Thode,
S. R. Smith,
F. D. Walkling,
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摘要:
Three 25 ft. columns packed with "Haydite" aggregate, a cheap efficient packing material, have been operated in cascade for 120 days to concentrate the oxygen isotopes by the distillation of water. In this time 23 gm. of O18in excess of normal were produced. This includes 150 ml. of water enriched 6.5-fold in O18and 2.7-fold in O17. The results indicate that these columns can be expanded to several feet in diameter for large scale production of O18without much loss in efficiency. Cohen's theory for the operation of packed fractionating columns explains satisfactorily the effect of rate of flow on the equilibrium fractionation and gives a production rate in agreement with our data. The vapour pressure of H2O17has been calculated and found to be equal, within the limits of our experiments, to the algebraic or geometric mean of the vapour pressures of H2O16and H2O18.
ISSN:1923-4287
DOI:10.1139/cjr44b-016
出版商:NRC Research Press
年代:1944
数据来源: NRC
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