摘要:

The treatment of chloranil (I) with alkali and 2-mercaptoethanol resulted not only in replacement of the chlorine atoms but also in reduction to form 2,3,5,6-tetrakis(β-hydroxyethylmercapto)-1,4-hydroquinone (II). The conditions for the preparation of 2,3,5,6-tetrakis(β-chloroethylmercapto)-1,4-hydroquinone (III) from II differed from those required for the preparation of a lower-melting compound (IV) from II by such a narrow margin that exact control of temperature and concentration were necessary in order to avoid erratic behavior in the preparation. The structure of the lower-melting compound has been established as 2,3-dihydro-5,7,8-tris(β-chloroethylmercapto)-6-hydroxy-1,4-benzoxathiin (IV) by analyses and cyclization reactions. The treatment of 2,3-dichloro-1,4-naphthoquinone (VIII) with 2-mercaptoethanol yielded 2,3-bis(β-hydroxyethylmercapto)-1,4-naphthoquinone (IX) and not the quinol as was the case with chloranil. The quinone (IX) could not be converted to 2,3-bis(β-chloroethylmercapto)-1,4-naphthoquinone by treatment with hydrogen chloride because under these conditions only 1,4-oxathio-5,10-anthraquinone (X) was formed. A mechanism for the formation of X which involves intramolecular addition, elimination, and cyclization is described.

ISSN:0008-4042    

DOI:10.1139/v62-191

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

A study of the hydrogen peroxide oxidation of phenylmercaptoacetic acid led to a new interpretation of the mechanism of the acid-catalyzed cleavage of phenylsulphinylacetic acid.

ISSN:0008-4042    

DOI:10.1139/v62-192

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The photodimer of coumarin is shown to have the head-to-head cis cyclobutane structure I. An isomer, obtained by the lactonization ofo-hydroxy-trans-cinnamic acid, is shown to have the head-to-tail trans structure II. The photodimers ofo-methoxy- ando-hydroxy-trans-cinnamic acids have been interrelated.

ISSN:0008-4042    

DOI:10.1139/v62-193

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The equilibrium diagrams of the systems NaNO3–LiNO3, LiClO3–NaClO3, LiClO3–LiNO3, NaNO3–NaClO3, and NaNO3–LiNO3–LiClO3–NaClO3have been investigated by thermal analysis and, to some extent, by X-ray powder photography. All the binary systems are of the simple eutectic type, accompanied, in one instance, by considerable solid solubility. The allotropic transformation of sodium nitrate complicates the equilibria involving sodium nitrate somewhat, especially when there is solid solution.The quaternary diagram shows that in the (fused) reactionlithium nitrate and sodium chlorate constitute the stable solid pair. The two invariant points of this system are both congruent.

ISSN:0008-4042    

DOI:10.1139/v62-194

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Linseed mucilage has been separated into an acidic and a neutral fraction. The acidic fraction was further separated, by the use of cupric acetate solution, into two fractions, CuI and CuII. Fraction CuI containedL-rhamnose,L-galactose, andD-galacturonic acid. The methylated reduced polysaccharide gave on hydrolysis 2,3,4-tri-O-methyl-L-rhamnose, 3,4-di-O-methyl-L-rhamnose, 4-O-methyl-L-rhamnose, 2,3,4,6-tetra-O-methyl-D-galactose, 2,3,6-tri-O-methyl-D-galactose, and 2,3-di-O-methyl-D-galactose (?);L-galactose was lost during the methylation process. Periodate oxidation studies on the material indicated that the polymer was composed of a main chain ofL-rhamnose units with most of theL-galactose units attached as non-reducing end groups. Fraction CuII containedL-rhamnose,L-fucose,L-galactose, andD-galacturonic acid. The methylated reduced polysaccharide gave on hydrolysis 2,3,4-tri-O-methyl-L-fucose, 2,3,4,6-tetra-O-methyl-L-galactose, 2,3,6-tri-O-methyl-D-galactose, 4-O-methyl-L-rhamnose,L-rhamnose, and possibly 2,3-di-O-methyl-D-galactose and 3-O-methyl-D-galactose. Periodate oxidation studies and a degradation by the Smith procedure indicated the presence of aL-rhamnose backbone withL-fucose andL-galactose units attached as non-reducing end groups.Theneutralfractionyielded a periodate-oxidizable material after one Smith-type degradation. Periodate oxidation studies indicated that the degraded material was branched. Methylation of the degraded polysaccharide followed by hydrolysis yielded 2,3,4-tri-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 2,4-di-O-methyl-D-xylose, 4-O-methyl-D-xylose,D-xylose, and traces of 2,3,4-trt-O-methyl- or 2,5-di-O-methyl-L-arabinose, 2,4-di-O-methyl-D-xylose, and 3-O-methyl-D-xylose. The main backbone of the degraded polysaccharide appeared to consist of (1 → 4)-linkedD-xylose units. Linkages of the (1 → 3) type were also present. The smaller fragments from the Smith-type degradation,L-arabinose, 2-O-α-L-arabinosyl glycerol, and glycerol were characterized. A partial acid hydrolysis of the neutral fraction yielded a number of oligosaccharides.

ISSN:0008-4042    

DOI:10.1139/v62-195

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Acid-catalyzed enolization of oxalacetic acid in H2O and D2O gives rise to a constant isotope rate effectof 2.4 over the pH (pD) range of 5.5 to 7.5. Base-catalyzed enolization of oxalacetic acid in H2O and D2O gives rise to a constant isotope rate effectof 4.5 over the pH (pD) range of 7.0 to 8.0. The percentage of enol form of oxalacetic acid was calculated to be 15.3% at pH 8.0, using the absorption of the enol form in ether at 255 mμ and the absorption of the keto form at pH 0.5 in an aqueous system. The spectrophotometric measurement of the isotope rate effect involved in the enolization of oxalacetic acid gives direct evidence for the rate-determining step in both the acid- and the base-catalyzed reactions without subsequent reactions.

ISSN:0008-4042    

DOI:10.1139/v62-196

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

In order to confirm the existence of specific molecular complexes in solutions of polar solutes inaromaticsolvents previously proposed, the temperature variation of the proton resonance shifts of the solutes acetonitrile,p-benzoquinone, and N,N-dimethylformamide in 5 mole% concentration in toluene were measured. The large temperature coefficients of the solute shifts observed strongly support molecular complex formation. For the same solutes dissolved in methylcyclohexane the temperature coefficients were negligibly small. The temperature at which onset of free rotation of the N-dimethyl group of N,N-dimethylformamide occurs is solvent and concentration dependent. These observations are consistent with the proposed geometry of the molecular complex in the aromatic solvents.

ISSN:0008-4042    

DOI:10.1139/v62-197

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The small HCN yield from the CH4and C2H6reactions in an unheated, cylindrical reaction vessel is greatly reduced in the presence of added NH3. The addition of NH3completely quenches the flame emission from the CH4reaction, and greatly reduces that from the C2H6and C2H4reactions. Both flame emission and HCN production from the CH4and C2H6reactions appear to be initiated, at reaction temperatures of about 83 °C, by an excited nitrogen molecule similar to that responsible for NH3decomposition.

ISSN:0008-4042    

DOI:10.1139/v62-198

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

Chlorine and tetrachlordiborine were the main products from the reaction of active nitrogen with boron trichloride. The maximum flow rate of chlorine recovered, about 4% of the available N-atom flow rate, was essentially independent of temperature in the range 100° to 395 °C. It is suggested that the reaction is initiated by (N2A3Σu+), and that this is followed by N-atom attack on the resulting BCl2radical. A similar mechanism is suggested for a slight extent of reaction observed with germanium tetrachloride.Hydrogen and germanous nitride (Ge3N2) were the products of the reaction of active nitrogen with germane. The amount of germane decomposed increased with an increase of temperature from 100 ° to 200 °C; at the higher temperature it corresponded to not more than two-thirds of the N-atom flow rate used. It is suggested that the reaction involves the direct and complete displacement of hydrogen by atomic nitrogen.

ISSN:0008-4042    

DOI:10.1139/v62-199

出版商:NRC Research Press    

年代:1962

数据来源: NRC

摘要:

The solid alcohol fraction of the oleoresin of the male fern was shown to contain two higher primary alcohols, 1-tricosano1 and 1-docosanol. The sterol fraction was found by means of chemical and spectrographic evidence to be 5,11(?)-stigmastadien-3β-ol.1-Tricosanol was synthesized from behenic (docosanoic) acid via tricosanoic acid, the latter being the product of Arndt–Eistert synthesis. 1-Docosanol was synthesized by LiAlH4reduction of behenic acid.

ISSN:0008-4042    

DOI:10.1139/v62-200

出版商:NRC Research Press    

年代:1962

数据来源: NRC