Phenylazoacetoacetanilide and its related compounds have the hydrazone structure. The phenylazoacetoacetic acid ethylester, for example, forms an intramolecular hydrogen bond between a ketone group and a hydrazone group in the solid state and in non-polar solvents. The electronic absorption spectra exhibit three groups of bands—A,B and C—D. The effects upon the spectra of the intramolecular hydrogen bond and of the π-p conjugation at the carboxylic acid amide group have been discussed.
Phenolazoacetoacetamides take the hydrazone form. The phenolic hydroxyl group forms an intramolecular hydrogen bond with a hydrazone nitrogen atom in the solid state and in non-polar solvents. The electronic absorption spectra of these compounds exhibit four groups of characteristic bands: The A bands arise from a transition involving electron migration along the whole conjugate system of the respective compound; the C bands originate in a conjugative electronic transition between a phenolic nucleus and a hydrazone group, and the D bands, in a conjugative electronic transition between a carboxylic acid anilide group and a hydrazone group. From the investigation of the series of spectra in phenolazoacetoacetbenzylamides, the B bands have been assigned to the conjugation band; they arise from a conjugative electronic transition within a partial chromophore consisting of an acetyl carbonyl and a hydrazone group.
1) The electronic absorption spectra of metallized phenolazoacetoacetanilides exhibit four characteristic groups of bands—A, B, C and D. These groups of bands originate in the band of the respective ligand-dye. 2) The metal-complexes have the structure shown in formula VI. 3) The bathochromic shifts of the A ligand-bands with complex-formation are ascribed to two causes: (i) the polarity of the M–O (M, tervalent metal; O, phenolic oxygen) bond, and (ii) the perturbation of the π-electron system by the dπ-pπ interaction. The shifts of the C ligand bands with the complex-formation are closely related to the polarity of the above-mentioned M–O bond. The cobalt (III)-complex has the covalent M–O bond with which to form a stable chelate ring, whereas the chromium (III)-complex has the ionic M–O bond. 4) The absorption characteristics of the iron (III)- and the aluminum-complexes have been discussed.
The electronic absorption spectra of the series of metallized phenolazoacetoacetanilides have been investigated. The substituent, in the o- or p- position to the M–O (M, central metal; O, phenolic oxygen) bond, generally alters the polarity of the M–O bond. On the other hand, the substituent, in the m-position to the M–O bond, i.e., the p-position to the hydrazone group, mainly contributes to the dπ-pπ interaction between the hydrazone group and the central metal atom. The effects of such substituents upon the shifts of the A bands are more pronounced in the cobalt (III)-complexes than in the chromium-(III)-complexes, because the former complexes have the stable five-membered chelate rings involving the highly covalent Co–O (O, phenolic oxygen) bonds.
The absorption spectra of metallized phenolazoacetoacetbenzylamides were investigated. The isolation of the electronic effect of the amide phenyl ring by the insertion of the methylene bridge decreases the intensity of the D band, resulting in the hypso- and hypochromic displacement of the A, B and C bands. The red-shifts of the A and C ligand-bands with the complex-formation indicate that the Co–O (O, phenolic oxygen) bonds increase their ionic character as compared with those of the metallized phenolazoacetoacetanilides. The splitting of the A band in the spectra of metallized 2-hydroxy-5-nitrophenylazoacetoacetbenzylamide is possibly to be attributed to the polarization of the M–O (O, phenolic oxygen) bond by the electron-withdrawing nitro group.
An investigation of the reactions between sym-metrically-parasubstituted benzoyl peroxides and iron (II) has been made. From the apparent first order specific reaction rates, which were obtained from the data of the thermal analysis method, the energy and entropy of activation have been estimated. In this reaction series, the linear enthalpy-entropy relationship was observed. William’s concept of the coördination of iron(II) to the peroxide molecule was assumed, and the effects of substituents on both the enthalpy of activation and the entropy of activation were discussed. It was also found that the Hammett’s equation is approximately applicable, except for nitrosubstituted benzoyl peroxide.
The decay of the activity of bright platinum electrodes activated by means both of electrolytic and chemical preoxidations have been studied under a hydrogen atmosphere. The life of the activity has been shown to depend upon the extent of the oxidation of the surface in the pretreatment. The structural change of surfare caused by the preoxidation appears to be responsibe for the enhanced activity.
1) Reaction of tetrahydrofuran hydroperoxide with ferrous sulfate produced hexane-1, 6-diol-diformate (13.8%), which was formed by the dimerization of 3-formoxypropyl radical generated from 2-tetrahydrofuranoxy radical, and γ-butyrolactone (31.4%) and 4-hydroxybutanal (trace). 2) In the presence of metal halide, the dimerization of the 3-formoxypropyl radical did not occur and halogenation of the 3-formoxypropyl radical was observed. For example, when tetrahydrofuran hydroperoxide was reacted with cuprous chloride and cupric chloride, 3-formoxypropyl chloride was obtained in a yield of 42.3%. 3) It is worth nothing that under suitable experimental condition the chloro compound was obtained in a good yield. 4) Probable reaction process was discussed.
The kinetic study of the substitution reaction of copper(II) ions and cobalt(II)-EDTA complexes in acetate buffer solutions has been carried out with the same procedure as that reported previously. The reaction was found to proceed, under the experimental conditions, through three simultaneous reaction paths similar to those found in the substitution reaction of copper(II) ions and lead(II)-EDTA complexes. The rate constants for three elementary reactions of those reaction paths were determined at ionic strength 0.2 at 5 and 15°C. A reaction path in which the dissociation of cobalt(II)-EDTA complex is rate-determining was not observed in this substitution reaction.
Valence-bond calculations of the angular dependency of the proton coupling constants of the methylene group in the ESR spectra have been carried out. If the rotation of the group is the only type of deformation, the cos2θ rule by McConnell seems to be valid. If the rocking of the group takes place, however, the angular dependency is entirely different from the cos2θ rule, and the deformation angle based on the rocking model is much smaller than that derived by the cos2θ rule. This finding has been applied to the unequal coupling constants of the two methylene protons of the allyl-type radical in polyethylene.
We have tested several models and their molecular orbital indexes of the rate-determining step of antioxidization by substituted phenols. Some molecular complex models have been found to be rational, though the problem of which of them is actually the true mechanism of the chain-breaking inhibition of autooxidation cannot yet be settled. Another possibility, that the earlier stage of the hydrogen abstraction reaction may be the rate-determining step, cannot yet be abandoned. The numerical calculations have been carried out on the KDC-I digital computer of Kyoto University.
The diamagnetic susceptibilities of several aliphatic and aromatic amines have been determined. The susceptibility contribution, of NH21+ is evaluated from the noninteracting aliphatic amines, and this value is used for calculation of χM of aromatic amines. The exaltations are attributed to the interactions in the system. An anomalous value for N3+ ion is obtained.
The amounts of rare earth ions dissolved in a potassium bicarbonate solution, as well as those of other metallic ions dissolved in potassium bicarbonate, potassium carbonate and ammonium carbonate solutions, have been measured. Moreover, the minimum concentrations of potassium bicarbonate, potassium carbonate and ammonium carbonate required to dissolve the precipitates of the metallic bicarbonate and carbonate completely has been determined, and the distribution coefficients, Kd, of the completely dissolved metallic ions between an anion exchange resin and a potassium bicarbonate, potassium carbonate or ammonium carbonate solution had been measured. On the basis of those findings, the dissolution and anion exchange behavior of the metallic ions has been discussed, and the applicability to an analytical separation has been described.
1) By measuring the conductivity of the solution of hexa-aquochromium(III) sulfate and potassium-chrome alum, the formation constant of the ion-pair [Cr(H2O)6]SO4+ has been calculated. 2) By measuring the pH, ion exchange separation and electrical conductivity of the heated solution of potassium-chrome alum and of the solution of the alum heated in the solid state, their ion compositions have been deduced. Appreciation is expressed to Messrs. Teruyoshi Fujishima and Tosuke Imamura for their help in the determination of the electrical conductivity.
The influence of temperature upon the Michaelis constant,Km, and on the breakdown rate constant, k3, has been investigated for the hydrolytic reaction of amylose catalyzed by crystalline Bacillus subtilis α-amylase at pH 5.85 (the optimum pH) over the temperature range from 6 to 40°C. It has been found that logKm and logk3 increase linearly with a decreasing reciprocal absolute temperature 1/T in the lower temperature range below 25°C, while above that point they tend to flatten out. On the other hand, the plot of logk3⁄Km versus 1/T has been found to be linear over the whole temperature range studied. Apparent thermodynamic quantities have been calculated from Km, k3 and k3⁄Km and their temperature dependences. The results have been examined kinetically in terms of two different mechanisms, the first assuming a three-step mechanism, and the second assuming the reversible denaturation of the enzyme molecule. It has been found that the former is reasonably consistent, but the latter is poorly consistent with the results. By combining these findings with the previous data of solvent effect, the non-electrostatic part of the entropies for the reaction processes has been discussed. The meaning of thermodynamic quantities obtained have been diccussed.
1) Microscopic and radiotracer studies have been made upon the diffusion of barium into a rutile single crystal. 2) In the microscopic observation, the diffusion layer of barium oxide in the rutile single crystal was confirmed to liquefy above 1300°C due to the formation of a eutectic mixture between both constituents. Below 1300°C solid phase diffusion prevails, and the diffusion layer consists of polycrystalline of a random orientation. 3) The diffusion coefficients of barium oxide in a rutile single crystal were measured by means of the radiotracer method using 133Ba. The diffusion coefficients obtained were 3.5×10−14∼2.4×10−13cm2/sec. in the range of 1100∼1200°C and 1.1×10−12 cm2/sec. at 1300°C. Between 1100°C and 1200°C, small differences seemed to be observed for the values obtained according to the direction of the diffusion in the crystal, but this is not conclusive. The large value of the diffusion coefficient at 1300°C was considered to be due to the liquefaction of the diffusion layer. The energy of activation was calculated to be 43 kcal./mol. (parallel to the c-axis) and 59 kcal./mol. (perpendicular to the c-axis).
A novolak resin of a higher molecular weight, as described by Burke et al., was not obtained. It was considered that the reaction of p-chlorophenol with s-trioxane proceeded as follows: (1) At first, a normal reaction of novolak formation proceeded. The molecular weight distribution was explained by Imoto’s theoretical equation (120°C, 4 hr.). The analytical value of C1% was rather close to the calculated value. (2) Then “ reformation reaction” started (120°C, 7 hr. and 150°C, 2 hr.).(3) Reformation took place rather vigorously, and the molecular weight distribution became close to Poisson’s distribution (150°C, 8 hr.). (4) A three-dimensional compound was formed, and the molecular weight of the soluble part was lowered (150°C, 11 hr.). (5) The molecular weight of the soluble part increased by the decomposition of the threedimensional compound and by the dehydrochlorination reaction (150°C, 24 hr.).
1) In the photosensitized reaction of cycloheptatriene vapor, toluene was produced as the result of isomerization. The amount of toluene formation decreases as the pressure of cycloheptatriene increases. Isomerization to toluene proceeds through the excited molecule, which may be collisionally deactivated. 2) The ESR experiments at low temperatures show that cycloheptatrienyl radicals are formed by electron irradiation. However, the yield of the radical formation is low, nearly equal to that of benzene. 3) In the radiolysis of liquid cycloheptatriene the G values of the gaseous products and toluene are very small. The G value of the polymer seems to suggest the low yield of the radical formation at the initial step. We concluded that the major part of the absorbed energy results in the formation of the excited molecule, the electronic energy of which is readily converted to thermal energy.
Two kinds of polymerization reactions, the condensation polymerization of sodium dihydrogen orthophosphate anhydrate (NaH2PO4) and the ring-opening polymerization of sodium trimetaphosphate, have been compared by determining the average degree of polymerization of the whole molecule, \barn0, and of each branch, \barn∞, and the average number of branches, B, per molecule. As a result, it has been concluded that the remarkable difference between these two reactions can be explained by simultaneous polymerization and depolymerization during the heating. In the case of the condensation polymerization, the polymerization process is more important because the removal of water needs much heating, while, in the case of the ring-opening polymerization, the depolymerization process is more important because the polymerization is completed almost immediately after the material is melted.
The crystal structure of chloral hydrate has been redetermined by the two-dimensional Fourier method and the least-squares method on the NEAC-2203 computer. It is monoclinic and belongs to the P21/c space group, with four molecules in a cell of the dimensions a=11.50,b=6.04,c=9.60Å and β=120.0°. The molecular structure of chloral hydrate is of the gem-dihydroxy compound type with the two OH groups in the staggered gauche-position referred to the adjacent C–Cl3 group. The molecules of chloral hydrate in the crystal are held together mainly by the van der Waals attraction of Cl…Cl and by the bifurcated hydrogen bonds of (Remark: Graphics omitted.). As a result of differential thermal analysis, a high-temperature phase has been found between 53.6° and the melting point, which was ascertained by X-ray diffraction powder patterns. Some of the molecules of chloral hydrate appear to dissociate into water and chloral and attain equilibrium with them. This is inferred from infrared study and from the chemical reactivity with the Schiff reagent.