摘要:

A series of phenoxymethyl 2-chloroethyl ethers has been prepared for testing as possible insecticides.

ISSN:0008-4042    

DOI:10.1139/v55-001

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The following new compounds were isolated from the vapor phase chlorination of butyne-1, butyne-2, and pentyne-1: 1,1,2,2-tetrachlorobutane, 2,2,3,3-tetra chlorobutane, 1,1,2,2-tetrachloropentane,trans-1,2-dichloro-1-butene,trans-2,3-dichloro-2-butene, andtrans-1,2-dichloro-1-pentene. Dehydrochlorination of 1,1,2,2-tetrachlorobutane and 1,1,2,2-tetrachloropentane gave 1,1,2-trichloro-1-butene and 1,1,2-trichloro-1-pentene respectively. Partial dechlorination of 1,1,2,2-tetrachlorobutane and 1,1,2,2-tetrachloropentane gavecisandtransisomers of 1,2-dichloro-1-butene and 1,2-dichloro-1-pentene respectively. 2,2,3,3-Tetrachlorobutane gave chieflytrans-2,3-dichloro-2-butene. 1,1,1,2,2-Pentachlorobutane and 1,1,1,2,2-pentachloropentane were prepared by chlorination of 1-chloro-1-butyne and 1-chloro-1-pentyne respectively.

ISSN:0008-4042    

DOI:10.1139/v55-002

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

In a search for antituberculous compounds of low toxicity, the isonicotinylhydrazones of monohydroxybenzaldehydes and of the corresponding aldehydophenoxyacetic acids were prepared. When testedinνiνo, the isonicotinylhydrazones of 2-formyl-phenoxyacetic acid and of 6-methoxy-2-formyl-phenoxyacetic acid showed the most marked antituberculous activity combined with low toxicity. The preparation of 6-methoxy-2-formyl-phenoxyacetic acid and of the isonicotinylhydrazone of 2-formyl-phenoxyacetic acid are described as representative examples. The results of microanalysis include data which define the antituberculous isonicotinylhydrazones of 2-hydroxybenzaldehyde, 4-hydroxybenzaldehyde, and 2-hydroxy-3-methoxybenzaldehyde (o-vanillin).

ISSN:0008-4042    

DOI:10.1139/v55-003

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

A new method for preparing thin films for use in beta-spectrometry and 4π-counting is described. These films, made of polyvinylchloride-acetate copolymer are readily prepared with superficial densities as low as 1 μgm. per cm.2The films have good tensile strength and show excellent resistance to acids, alkalies, and many organic reagents. The thickness of the films may be determined (a) gravimetrically, (b) radiometrically, and (c) optically either by transmission or reflection. The films can be made conducting by distilling a thin gold layer on to them. The thickness of the gold layer can be determined spectrophotometrically.

ISSN:0008-4042    

DOI:10.1139/v55-004

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The yields of vanillin and syringaldehyde obtained by the alkaline nitrobenzene oxidation of aspen wood meal have been determined at various temperatures for various times. The maximum yield of each of these aldehydes,ca. 15 and 36% respectively, was obtained under the same conditions. Similar maximum yields result at 130 ± 5 °C. as at 170 ± 5 °C. if the reaction time is markedly increased. Treatment of the wood meal with sodium hydroxide at 160 °C. for two and one half hours prior to the addition of nitrobenzene and subsequent heating under the same conditions decreases, by over 30%, the yields of aldehydes. Samples of 3,4,5-trimethoxybenzaldehyde, β-D-glucovanillin, and β-D-glucosyringaldehyde were oxidized by alkaline nitrobenzene at 160 °C. for two and one half hours and yields of the corresponding phenolic aldehydes of 10.7, 69.6, and 71.9% respectively were obtained. These results are discussed with respect to the chemistry of aspen lignin.

ISSN:0008-4042    

DOI:10.1139/v55-005

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Azomethane has been photolyzed in the presence of CH3CHO and CH3CDO, and the results compared with the direct photolysis of the aldehydes. The activation energies found were 6.8 and 7.8 kcal./mole, respectively, for the reactionsThe results furnish evidence that only an acyl hydrogen is captured. Evidence has also been found for the occurrence of wall reactions and the disproportionation reaction

ISSN:0008-4042    

DOI:10.1139/v55-006

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The photolysis of biacetyl has been reinvestigated. The results are, in general, in excellent agreement with those of Blacet and Bell. Curvature occurs at low temperatures in the Arrhenius plot of[Biacetyl], and this is attributed to wall reactions, and to the disproportionation reactionAzomethane–biacetyl mixtures have been photolyzed to give further information on these points. An activation energy of 8.5 kcal. has been found for the reaction of methyl radicals with biacetyl.

ISSN:0008-4042    

DOI:10.1139/v55-007

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The photolysis of acetone has been investigated at room temperature using low pressures and high intensities. In addition an investigation was made of the photolysis of azomethane–acetone mixtures. The results indicate that the curvature at low temperatures of Arrhenius plots of[Acetone] is due to two causes (a) a reaction between methyl radicals and adsorbed acetone and (b) to the occurrence of the disproportionation reactionConfirmatory evidence for wall effects was obtained from experiments at low pressures and higher temperatures.

ISSN:0008-4042    

DOI:10.1139/v55-008

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The hemicellulose prepared from wheat bran by alkaline extraction was an acidic polysaccharide containing arabinose (50.0%), xylose (38.5%), and uronic acid (9.0%). Graded hydrolysis with 0.02 Noxalic acid preferentially released 65% of the arabinose with only a small simultaneous production of xylose. Hydrolysis of the full methylated hemicellulose yielded 2,3,4-tri-O-methyl-, 2,3-di-O-methyl-, 2-O-methyl-, and freeD-xylose; 2,3,5-tri-O-methyl-, 2,5-di-O-methyl-, and probably 3- and 5-O-methyl-L-arabinose. These data, together with those from periodate oxidation, strongly suggested that the molecule was a highly branched araboxylan. Viscosity measurements and reducing power determinations indicated a degree of polymerization of 300.

ISSN:0008-4042    

DOI:10.1139/v55-009

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Vanillin almost instantly reduced 1.2 to 1.5 moles of aqueous chlorine dioxide at 20 °C. or 5 °C. and any pH between 1.2 and 6.5, and a white crystalline substance with the composition of a dihydroxyvanillin, C7H5O4(OCH3), was isolated in roughly 25% yield independently of the pH. When oxidized with aqueous sodium chlorite at 20 °C. and pH 0.5, these crystals gave another crystalline substance with the composition of a dihydroxyvanillic acid, C7H5O5(OCH3). Although both these substances decomposed readily to red oils and then to brown powders free of methoxyl groups, seven well characterized derivatives were prepared. The results showed that the substances were unsaturated, monohydroxy, diketone tautomers of a dihydroxyvanillin and the corresponding dihydroxyvanillic acid, but precise structures could not be assigned. Parallel oxidations of vanillin with aqueous sodium chlorite at 20 °C. and pH 6 proceeded at a negligible rate, but near pH 5 a reaction that often seemed autocatalytic produced about 19% of 5-chlorovanillin. At pH 4 the aldehyde C7H5O4(OCH3) was isolated in 19% yield; at pH 1 this aldehyde (15%) was mixed with 7.7% of the corresponding acid C7H5O5(OCH3), but at pH 0.5 the latter alone was produced (28%). Chlorine dioxide and sodium chlorite therefore differed markedly in their oxidizing action and in the effect of pH upon it. When acting on vanillin, both oxidants also produced deep red, unstable oils with quinone-like properties and often containing chlorine.

ISSN:0008-4042    

DOI:10.1139/v55-010

出版商:NRC Research Press    

年代:1955

数据来源: NRC