摘要:

The fission of methanol from the diastereomeric 2,5-dimethoxy-2,5-dimethyl-3,4-diphenylhexanes leads to products which are best explained in terms of restriction about the central carbon-carbon bond. As would be expected from its stable conformation thedd,lldiastereomer easily forms the 2,2,5,5-tetramethyl-3,4-diphenyltetrahydrofuran, but themesodiastereomer forms a tetrahydrofuran with difficulty. On the other hand themesodiastereomer readily undergoes Friedel-Crafts types of condensation leading in different media to either 3,3-dimethyl-1-isopropenyl-2-phenylindane, 3,3-dimethyl-1-isopropyl-2-phenylindene or 5,5,10,10-tetramethyl-4b,5,9b, 10-tetrahydroindeno[2,1-α]-indene. These indenes are the expected products from a consideration of the conformation of themeso-dimethoxydimethyldiphenylhexane which is most free from steric restriction.

ISSN:0008-4042    

DOI:10.1139/v54-094

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The dielectric constant and dielectric loss factor were measured in a dispersion region for a paper of high cellulose content. The complex arrangement of the paper in the measuring condenser did not effectively alter the position of the dispersion region of the paper itself, as shown by electrical analysis. From this analysis equations were derived from which the dielectric constant and maximum dielectric loss factor of the cellulose fiber were evaluated for varying amounts of sorbed water, methanol, and ethanol. The effect of each of these vapors on the position of the dispersion region was studied, measurements being performed over a range of frequency of 10 to 1000 kc.p.s., and a range of temperature of −58 to 26 °C. A typical plasticizing action was observed in all three cases. This was confirmed from an analysis of the data using the theory of absolute reaction rates.

ISSN:0008-4042    

DOI:10.1139/v54-095

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Measurements of the reduced viscosity of suspensions of glass spheres 5 μ diameter have been made up to concentrations of 18% by volume. The experimental results yield the empirical equation ηsp/c = 2.50 + 12.7c + … The coefficient ofc, due to interactions, is in fair agreement with a value of 10.05 based upon a modification of Vand's theory which takes into account the experimentally established mechanism of two-body collisions of spheres in a velocity gradient. Several reasons for the discrepancy are suggested.

ISSN:0008-4042    

DOI:10.1139/v54-096

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The thermal decomposition of dimethyl disulphide has been studied in the gaseous state by a static method. The primary reaction, which follows a reproducible induction period, produces one mole of methyl mercaptan per mole of disulphide, together with a product of low volatility believed to be a thioformaldehyde polymer:There is also a competing reaction producing a large quantity of hydrogen sulphide. The remaining volatile products, hydrocarbons of two or more carbon atoms (believed to be chiefly ethylene), free sulphur, polysulphides, and carbon disulphide are formed either by the latter reaction or by the extensive decomposition of products. The decomposition is catalyzed by hydrogen sulphide, and more strongly by the complete reaction mixture. A mechanism is proposed for the main reaction.

ISSN:0008-4042    

DOI:10.1139/v54-097

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Reanalysis of delcosine and several of its derivatives shows that the most likely empirical formula is C24H39O7N. Delcosine has been shown to be identical with Goodson's base C. Acetylation produces monoacetyldelcosine, identical with Goodson's naturally occurring base B. It has been possible to prepare two isomeric diacetyl derivatives, one of which has been reported previously, and a further acetylated compound also reported previously which seems to have lost the elements of water. A dipropionyldelcosine is also described. The base contains three methoxyls and four hydroxyls, only two of which are acetylated readily.

ISSN:0008-4042    

DOI:10.1139/v54-098

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Ethyl α-acetoxy-2-pyridineacetate and ethyl α-bromo-2-pyridineacetate have been prepared, and the latter converted in three steps to 1,2-dicarbethoxy-3-oxooctahydropyrrocoline. The main carbonyl band of simple saturated five membered lactams in the infrared is observed to lie close to 1700 cm−1

ISSN:0008-4042    

DOI:10.1139/v54-099

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Benzoylbenzoic acid-carboxyl-C14has been synthesized. The C14isotope effect in the condensation of this acid to anthraquinone-9-C14in concentrated sulphuric acid has been measured and the ratio of the reaction rates,k(14)/k(12), found to be 1.074 ± 0.003. It is suggested that this result supports the mechanism for this reaction proposed by Newman.

ISSN:0008-4042    

DOI:10.1139/v54-100

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Mayer's theory gives a good representation of the apparent molal volumeof sodium chloride in aqueous solution at 25 °C up to a concentration 0.4 molar. Representation of the relative apparent molal heat contentis also satisfactory but over a smaller range of concentration. The shape of thecurve is strongly influenced by the temperature dependence of the distance of closest approach of oppositely charged ions in the solution. Methods of evaluating this term are considered. The utility of Mayer's theory for the extrapolation of experimental data to infinite dilution is illustrated in the case ofand of intermediate heats of dilution.

ISSN:0008-4042    

DOI:10.1139/v54-101

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v54-102

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v54-103

出版商:NRC Research Press    

年代:1954

数据来源: NRC