1,2,3,4-Tetrahydro-5-hydroxy-1-naphthylacetic acid has been obtained from 2-methoxy-5-hydroxy-1-naphthylacetic acid by reduction either with sodium and n-butanol, or with lithium and liquid ammonia-ethanol. In the former case, under moderate conditions, 1,2,3, 4-tetrahydro-2-oxo-4, 5-dihydroxy-1-naphthylacetic acid has been isolated as a by-product.
The kinetics of silver catalyzed oxidation of arsenious acid has been followed by estimating the acid with the permanganate. The results are reproducible only with the same stock solution of arsenious acid. This oxidation is much faster than other silver catalyzed oxidations, such as those of Cr3+, VO2+, Mn2+, Ce2+, etc. The oxidation is of the first order in persulfate and independent of the concentration of the acid. The entropy of activation has been calculated and a mechanism has been suggested. No conclusion regarding the salt effect could be obtained due to the specific effect of the ions. K+, Na+, NH4+ and Mg2+ inhibit in the order given. Nitrate ion accelerates the rate and sulfate ion seems to have no effect.
Two new complexes, sodium di-monothiophosphato-bis-ethylenediamine cobaltate(III) octa-hydrate and monothiophosphato-bis-ethylenediamine-cobalt(III) dihydrate, have been synthesized by the reaction of trans-dichloro-bis-ethylenediamine cobalt(III) chloride with anhydrous sodium monothiophosphate in cold aqueous solution. The infrared and the visible and ultraviolet absorption spectra of these compounds and of the corresponding thiosulfato-Co(III) complexes have been measured and discussed in relation to the structures of the complexes.
The apparent dissociation constant of alginic acid was measured by means of the neutralization with 0.1 N potassium hydroxide in 1 N potassium chloride solution and found to have a value of 3.1. This value is between that of IR-120 and of IRC-50, which is obtained by the same manner of measurement. The values of Kd for thorium(IV) and cerium(III) ions in regard to these three exchangers were measured, showing that the value in regard to alginic acid is also situated between the other two. The application of alginic acid to the fractional separation of thorium(IV) and cerium(III) ions gave a satisfactory result.
1) The ultraviolet absorption spectra of biphenyl in the crystalline state, in the solution state, and in the vapor state have been discussed in detail. 2) The relation between the position of conjugation band in the spectra of biphenyl and the spatial configuration of the molecule has been clarified by calculations based on the simple LCAO molecular orbital method. 3) By using the results of the calculations, it has been inferred from the analysis of the absorption spectra that the angles between the planes of the two benzene rings in the most probable conformations of biphenyl in the solution state and in the vapor state are about 20°C and about 40∼43°C, respectively. These values coincide fairly well with the values estimated by other workers on different grounds.
The method described in the preceding part of this series has been applied with allowance for the electronic bathochromic effect of the substituents to o-alkyl- and o,o′-dialkylbiphenyls, and the relation between the ultraviolet absorption spectra and the most probable spatial configurations of these compounds has been clarified, resulting in the conclusion that the interplanar angle in o-methylbiphenyl as well as its analogues is about 60°C and that o,o′-dimethylbiphenyl as well as its analogues has the cis-configuration in which the interplanar angle is about 70°C. On the basis of the result, the interpretation by Braude and Forbes of the spectra of o-methyl- and o,o′-dimethylbiphenyl has been criticized. In addition, the inferred spatial configurations of these biphenyl derivatives have been correlated with some physical and chemical properties of these and some related compounds.
The ultraviolet absorption spectra of some o,o′-bridged biphenyls and their relations to the spatial configurations have been discussed. The method developed in the earlier parts of this series has been applied to these compounds, especially o,o′-three-atom-bridged (o,o′-7-memberedring-bridged) and o,o′-four-atom-bridged (o,o′-8-membered-ring-bridged) biphenyls, and the interplanar angles have been calculated to be about 44.5∼47.3° (average, 46°) for the former compounds and about 58.0∼61.5° (average, 59.8°) for the latter.
The effect of dry grinding on gibbsite was examined by X-ray diffraction, X-ray small angle diffraction and differential thermal analysis. It has been found that there are two sorts of structural change in the process of dry grinding. One, which occurs early in this process, is the slip of layers. In this stage (002) reflection retains its intensity. The other, which takes place after grinding of about 10 hr., is the three-dimensional disintegration of the crystal structure and the intensities of all diffractions become weak. Since only two reflections (002) and (110) are observed after 40 hr., it can be known that the direction of the slipping of layers is . DTA-curve of gibbsite exhibits three endothermic peaks in the beginning of grinding but comes to exhibit only one peak which indicates the decomposition of gibbsite to alumina. This means that ground gibbsite decomposes directly to χ-alumina as fine gibbsite and boehmite is not produced in this process.
The effect of acetate ions on the rate of the substitution reaction of copper(II) and lead-EDTA complexes is explained quantitatively on the basis of the formation of acetato complexes of copper (II) and lead(II) in acetate media and on the assumption that the substitution reaction proceeds only through the hydrated metal ions. The rate constants, the heats of activation and the entropies of activation for three elementary reactions are recalculated with the experimental results obtained previously.