摘要:

Electrode potentials of indium and gallium couples have been measured in dilute solutions of the ionic species in fused LiCl–KCl eutectic at 450 °C. Standard molar electrode potentials of the observed couples are −1.210, −0.944, and −1.136 V against a standard molar platinum reference for the In(I)–In(0), In(III)–In(I), and Ga(III)–Ga(0) couples, respectively. These oxidation states and potentials are compared with previous work in this and other fused salt systems.

ISSN:0008-4042    

DOI:10.1139/v70-353

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The reaction 2I + SO2 → I2 + SO2has been studied between 293 and 668°K. At 293°K, the recombination rate constant is 2.6 × 1010]2 mole−2 s−1; it attains 1/10 of this value at 668°K. Although the infrared and ultraviolet spectra of SO2, studied previously, suggest the existence of two forms of SO2in the temperature range in question, the present recombination studies present no further supporting evidence about the existence of the excited form.

ISSN:0008-4042    

DOI:10.1139/v70-354

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The geminal coupling constants between the non-equivalent benzylic protons of a series of para- and meta-substitutedN-benzyl-2-methylpiperidines were shown to be proportional to the Hammett σ constants of the substituents with ρ −1.38 in carbon tetrachloride, −1.21 in benzene, and nearly 0 in 1 NDCl solutions. The ρ values were compared with those of other series and were discussed in terms of the possible conformations involved. The chemical shifts of the benzylic protons of the piperidine derivatives did not give a good correlation with the Hammett σ constants in these solvents.

ISSN:0008-4042    

DOI:10.1139/v70-355

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Selectivity and yield were studied in the reaction of 5-chloro-1-phenyltetrazole with dihydroxytoluene systems. The mono-ethers of 2-methylhydroquinone (1a), 3-methylcatechol (2a), and 4-methylcatechol (3a) were formed in moderate yields with the predominant isomer resulting from attack by the more nucleophilic anion. With1aand2a, steric effects diminished the amount of predominant isomer formed as compared to3a. The di-(1-phenyltetrazole) ethers were formed in good yields. Hydrogenolysis of mono- and di-ethers gave good yields of cresols and toluene as determined by gas chromatography and ultraviolet analysis, respectively.

ISSN:0008-4042    

DOI:10.1139/v70-356

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

3-Alkylthio-1,2,4-dithiazolium salts are most conveniently made by alkylation of the corresponding 1,2,4-dithiazole-3-thiones by dimethyl sulfate. These salts readily undergo nucleophilic attack by amines in position 3, with loss of a methylthio group. Hydrogen peroxide oxidation, or chlorination, of the thiones gives the corresponding dithiazole-3-ones.

ISSN:0008-4042    

DOI:10.1139/v70-357

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

Hydrolysis of 4,6-O-benzylidene-3-deoxy-3-C-(iodomethyl)-D-allal (1) in neutral buffered medium with or without silver ion assistance gives the cyclopropyl aldehyde4as the only product. Methanolysis of1gives an equal mixture of the α and β anomers of methyl 4,6-O-benzylidene-2,3-C-methylene-2,3-dideoxy-D-allopyranosides (6and7). These results indicate that thecyclopropylcarbinyl-oxo-carboniumion(2), is produced with unit efficiency in solvolyses in neutral media, and the formation of both diasteriomers (6and7) requires the complete absence of bicyclobutonium ion (9) resonance contribution to the stabilized intermediate, and implies a strong contribution from the oxo-carbonium ion10. In basic media compound1undergoes quantitative dehydroiodination to the conjugated diene, 4,6-O-benzylidene-1,2,3-trideoxy-3-C-methylene-D-ribo-hex-1-enopyranose(8).

ISSN:0008-4042    

DOI:10.1139/v70-358

出版商:NRC Research Press    

年代:1970

数据来源: NRC

摘要:

The effect of solvent on the stereochemical course of deuteration of benzyl methyl sulfoxide has been studied by two methods. In the first, the relative rates of exchange of the diastereotopic methylene protons were found to vary from 14:1 (D2O/NaOD) to 0.5:1 (t-butanol-OD/NaO-t-butyl). Experiments on quenching α-lithiobenzyl methyl sulfoxide with D2O gave the same diastereomers in ratios ranging from 1.7:1 (DMSO) to 0.065:1 (THF). The significance of these findings in relation to previous work on conformational stabilities of α-sulfinyl carbanions is discussed.

ISSN:0008-4042    

DOI:10.1139/v70-359

出版商:NRC Research Press    

年代:1970

数据来源: NRC