Surface properties of magnesium hydroxide which adsorbed soluble silica were investigated in comparison with magnesium silicate gel. Surface area increased with increasing amount of adsorbed silica it was attributed to the formation of micropores. The formation of -Mg-OSi- bonds by the adsorption brought about an acidic nature on the surface. The total acidity (Ho< +3.3) also increased with increasing amount of adsorbed silica. The surface products formed by the adsorption were isolated by dissolving bulk magnesium hydroxide with an ammonium chroride solution, and their properties were examined by means of IR spectroscopy, DTA, X-ray diffraction, and chemical analysis. The properties were similar to those of magnesium silicate gel. It was presumed from the experimental results that more amounts of silica adsorbed than those to form a monolayer did not bond to the monolayer silica, but bonbed to the first layer of Mg atoms from the direction of bulk side or to the second layer of Mg atoms.

View full abstract

Samples of La, MnSr, O, in the range 0 s x s 1 were prepared by co-precipitating the nitrates of La, Sr and Mn with ammonia and hydrogen peroxide and used as catalysts for the oxidation of CO. The effects of strontium incoporation on the crystal structure and the amounts of surface oxygen were investigated by the X-ray diffraction, oxygen adsorption and KI-methods.
Catalysts with x so.8 had single-phase perovskite and the cell size decreased with the increase in x. Chemical analysis of the catalysts showed the presence of oxygen vacancies for 0.7 s x s O.8, at which CO was oxidized at maximum rates the orders of the reaction were approximately 1 and 0.5 with respect to the pressure of CO and 02 respectively. The amounts of reversibly adsorbed oxygen showed the minimum values in this range of x. The amounts of surface oxygen as measured by the KI-methods were greatly affected by those of surface manganese ions of the catalysts. It was concluded from these results that the oxygen vacancies introduced with the Sr incoporation greatly affect the catalytic activity by changing the oxygen adsorption state.

View full abstract

Steam dealkylation of alkylbenzenes over Rh/MgWO₄ catalyst was compared with that over other catalysts, i. e., Rh/A1203, Rh/Cr203, and Rh/MW04 (M- Be, Ca, Sr, or Ba).
The turnover number for Rh/MgWO₄ catalyst was about four times as high as that for Rh/A1203 catalyst. The high activity of Rh/MgWO₄ catalyst was attributed to the promoting action of MgWO₄ for the elementary step (d and e) in the following reaction pathway:
On the basis of the benzene content in the liquid products it was considered that benzene rings in adsorbed alkylbenzene molecules oriented parallel to a rhodium surface.

View full abstract

As a fundamental research on the storage of hydrogen by using mental hydrides, the absorption-desorption characteristics of hydrogen for mischmetal based alloys were investigated. The relation among pressure, temperature and composition was examined for the alloy-H systems. Both MmNi5 and MmCo, have the same hexagonal structure as LaNi5, and they reacted readily with hydrogen to form hydrides of MmNi5I-18.3 and MmCo51-13.0 under 60 atm hydrogen pressure and at room temperature. The enthalpy changes in hydride formation determined from the dissociation isotherms (Fig.2) were 6.3 kcal/mol and 9.6 kcal/mol, and the dissociation pressure at 20° C was 13 atm and 0.6 atm, respectively. The desorption rates of hydrogen for MmNi5 and MmCo, were increased with increasing temperature. MmNi, had been subjected 110 times to hydrogen absorption-desorption cycles, and the variation in hydrogen absorption ability was almost not recognized.
Hydrogen absorption and desorption characteristics of alloys such as Mm, rAsNi, and Mm, x A, Co, (A: Ti, Ca) were also investigated; Mm, xTizNi, (x=0.1-0.25) and Mmi_xCaxNi, (x=0.1-0.75) reacted readily with hydrogen to form the hydrides at room temperature. It was found that dissociation pressure of Mmi xTixNi, hydride was getting higher than that of MmNi, hydride with increasing x, while that of Mm1_sCazNi5 hydride decreased when taking x>0.5. The hydride of Mmo., Cao., Ni, showed properties suitable as a hydrogen storage material since it had the dissociation pressure of 5 atm at 20° C, and the enthalpy change of 7.6 kcal/mol.
In the case of Mm, , TizCo5, Mno, , Tio., Co, reacted with hydrogen to form hydride of Mmo.9Tio.1Co5H3.4, and alloys absorbed almost no hydrogen over the composition of x=0.75.

View full abstract

In an attempt to use calcium sulfite hemihydrate (CaSO3.1/2 H₂O) as an inorganic filler in plastic composite, the hemihydrate crystals of different shapes were prepared either by dropping CaCl2 solution into Na₂SO₃ solution or by passing a stream of SO₂ through the suspension of Ca (OH) 2. Characteristics of each inorganic filler, such as particle size, crystalline degree, surface property and thermal stability, were investigated.
Under controlled synthetic conditions the CaCl2-Na₂S03 reactions yielded hemihydrate crystals of different shapes, i. e. chestnutburr (c 5, um), needle (17 x 0.7, urn), pillar (14 x 2, um) and planar (50x50 pm) crystals. Similarly, the Ca (OH) 2-SO₂ reaction system led to the formation of fine particles (0.05, um), needle (0.5 x 5, um) and planar (6 x 9 or 4 x 4, um) crystals according to the reaction conditions involved. Each crystal shape was identified from the intensity ratio of characteristic peaks on the X-ray diffraction pattern so that the orientation of their crystals differed remarkably. On the other hand, the surface modification of the hemihydrate was made possible by dropping CaCl2 solution into Na₂S03 solution containing Cl7H35COONa under the most suitable synthetic condition for each crystal shape. Thus, its surface changed into hydrophobic from hydrophilic without changing any crystal shape.
From the thermal analysis (TG-DTA) of each crystal of different shape, the thermal behavior of the hemihydrate in dehydration and oxidation turned out to differ remarkably in accordance with crystal shapes. Thus, the activation energy for dehydration ranged from 204.8 kJ/mol for the chestnutburr crystal to 390.4 kJ/mol for the planar crystal. A characteristic exothermic peak due to the combustion of PVC in PVC composite was not found on DTA curves of the PVC composite containing the hemihydrate, so that the water of crystallization in CaSO₃.1/2 H₂O should act as a flame retarder. A new double salt phase appeared in the Ca (OH) 2-502 system, being confirmed as a double salt of CaS03-CaSO₄ system by Xray diffraction.

View full abstract

The phosphorus ligand exchange of trans-[M11(O-CH, C, H4)X (PPh3) 2] (M=Ni, Pd, Pt; X=Br, I) was investigated by means of "P-NMR spectroscopy. With tertiary phosphine ligand, the triphenylphosphine ligand is readily replaced in chlorobenzene solvent in the following order: PPhMe2, =PPh2Me>P(p-C61-140Me) 3 > P (P-C6H4Me) 3 > P (P-C6H4F) 3=P (p-C6H4Cl) 3>>>P (O-C6144- 0Me), P(o-C. H, Me), and also with phosphite ligands, in the following order: P(OMe)3> P(OEt)3>P(O-i-Pr)3>>>13(OPh)3. This result indicates that steric factor predominantly more contributes to the exchange reactions than electronic factor. It is worthy of notice that the exchange reaction with trimethyl phosphite gives a zerovalent nickel complex, Ni [P (OMe) 3]4, which is formed presumably in terms of a reductive elimination of o-bromotoluene. The exchange reactions of Ni (o-CH₃C6H4) I (PPh3) 2 and Pd (o-Cl-13C6H4) I (PPh3) 2 with typical phosphorus ligands were also examined.

View full abstract

Water contents of fluorine bearing minerals have been determined by the Karl Fischer titration method. By using the tube-filling materials which had been reported in the previous paper, hydrogen fluoride released by heating from the minerals was converted in to water quantitatively. In this paper, the effect of heating temperature on water release and an analytical precision of the proposed method are reported. In a platinum crucible the weighed sample (150-250 mg dried at 110°C) was provided. The crucible was placed in the analytical apparatus. After passing a purified nitrogen to sweep water adsorbed on the apparatus, residual water in the gas was determined with Karl Fischer reagent (Blank Test). The sample was heated at 1100-1500° C in an induction furnace in the carrier gas of constant flow rate. Volatile substances released from the sample were introduced into the tube-filling materials, and then the total water was determined by the same method as that in the blank test.
In order to determine the temperature above which all water in the sample was expelled, the effect of the heating temperature on water release was tested and the results are shown in Figs.1-4. All water was removed from tourmaline or axinite at about 1100° C during 120-50 minutes. But several minerals, such as topaz, epidote, hornblende, some muscovite, biotite, phlogopite, and apatite, did not release all water below 1200° C. The heating tempera ture varied markedly with types of minerals and fluorine contents in the minerals. When the fluorine contents in the sample were high, it was necessary to rise the heating temperature. For biotite which contains 0.25, 2.79, or 5.68% fluorine, it was required to heat it at 1200°, 1420°, or 1460° C, respectively. For phlogopite, whose fluorine content being 2.00 or 3.23%, it was needed to heat it at 1200° or 1350° C, respectively.
The analytical precision of the proposed method was satisfactory. The 95% confidence limits of water found were 4.26± 0.03% or 4.55± 0.04% for muscovite, 3.44+ O.03% for phlogopite, and 3.43± 0.01% for biotite.

View full abstract

A highly sensitive method has been developed for the determination of trace amounts of cobalt based on the catalytic action of cobalt on the oxidation of Gallocyanin (GAL) by hydrogen peroxide. Since GAL was oxidized to decolorized product in the presence of cobalt in weakly alkaline solution, difference of absorbance (ΔE) between reagent blank and sample solution was used to determine cobalt by the fixed time method, the absorbance being measured at the absorption maximum of GAL (520 nm).
A linear relationship was obtained between zIE and concentration of cobalt in the range between 0.2 and 2.4 ng/ml under the following conditions;
GAL: 1.6 x 10-3 mol/l, H₂O2: 2.4 x 10-1 mol/l, pH: 9.4 (borate buffer),
Mg(II): 2.4 Pg/m/, Temp.: 25° C, Reaction time: 10 min.
In this method, an apparent molar absorptivity was 1.6 x 107(l/mol.cm). Among diverse metal ions, 300 times of iron (III) and 2000 times of chromium (III) interfers with the determination. Amounts of 100 times of nickel do not interfer. The coefficient of variation of the analytical result was 4.6%. Present method was succesfully applied to the determination of trace cobalt in lake water.

View full abstract

The electrodless discharge lamp of NO was developed and used as a light source for the determination of NO by molecular absorption spectrometry. This lamp was operated under frequency of 27 MHz. The lamp containing N203 and N2 gas at pressure of 1 to 5 Torr in a quartz tube was designed to be mounted within the cavity. The 8 and r spectra of NO molecular in the 190.0 to 280.0 nm and the much intense N2 and N2+ band spectra in the 280.0 to 500.0 nm were detected from this lamp. The most intense wavelength was 236.3 nm (0, 1) in all the NO emission bands. For determination of absorption spectrum, a quartz tube of 300 mm long was used as an absorption cell.
The absorption spectra of the NO bands were obtained at 214.9, 204.7, 226.3, 195.6 and 236.3 nm. Sensitivity values (ppm for 1% absorption) for NO were 0.83 ppm at 214.9 nm, 1.18 ppm at 204.7 nm, 1.6 ppm at 204.7 nm and 14 ppm at 236.3 nm. The detection limit for NO at 214.9 nm was 0.04 ppm.

View full abstract

In order to apply the pulse-FT-¹³C NMR spectrometry to quantitative analysis, the quantitative relationships between ¹³C NMR signal area intensity and number of resonating nuclei were investigated. CH, carbon signal area intensity ratios (S. A. R.) of (C-3 or more carbon/ C-2 carbon) in normal paraffines were found to approach to theoretical ratio with increasing pulse delay (PD) and with decreasing pulse width (PW) as shown in Fig.2. In the case of tetradecane, the proportional relationship between S. A. R. and theoretical ratio was held with relative error 10%, under PW= 20, u sec and PD=5 sec conditions as shown in Table 2.
¹³c Signal area intensity and signal-to-noise ratio (S/N) of carbonyl carbon in acetonemethyl acetate mixture were greatly influenced by PD and PW condition as shown in Fig.4. The relative error for the determination of acetone in acetone-methyl acetate mixture was found to be 3%, under PD= 5-15 sec and PW= 60, u sec as optimum pulse conditions as shown in Table 3.
The relative content of each component in o-, m- and p-tolyl acetate mixture was determined by measuring the signal area intensity ratio of the ring carbon bonded to OAc group or CH, group and the carbonyl carbon in OAc group. The relative error for the determination of o- and m-isomer in o-, m- and p-tolyl acetate mixture was found to be about 6%, under PD= 15 sec and PW= 60 g sec as shown in Table 5.

View full abstract

An ultra-micro amount of thallium could be determined by the isotope dilution-surface ionization mass spectrometry by using 20311 as a spike. After thallium was separately extracted into 10 ml of 0.00125/ dithizone chloroform solution from the solution of the sample isotopically equilibrated with the 203T1 spike, it was back extracted into 5 ml of 1% nitric acid. The nitric acid solution was treated with a mixture of 0.2 ml of 14 N nitric acid and 0.1 ml of 60% perchloric acid, and evaporated to dryness in a pyrex glass oven supplied with highly pure nitrogen. The residue was dissolved in a mixture of 60, u/ of water with 0.015% silica gel suspension and 5 xtl of 2% phosphoric acid solution. An aliquot of this mixture was loaded onto a rhenium single filament as an ionization equipment of a Hitachi RMU-6 type mass spectrometer. The detection limit of the present method was 10-15-10-14 g for thallium. The precision concerning mass spectroscopic analysis, as a coefficient of variation for the measurements of 205T1/203T1 ratios, was 0.1-0.5%. The application of the present method to environmental materials such as Japanese standard rocks and Orchard Leaves delivered by N. B. S. has shown that the precision of repeated analyses was 0.2-0.7% for a concentration of ppm level. This method has revealed that concentration of thallium in the ocean increased with increasing depth at a ppt level.

View full abstract

The kinetics of the reactions of N-methylmaleimide (MMI) with L-cysteine (CySH), 3- mercaptopropionic acid (PaSH) and 2-aminoethanethiol (AeSH) have been studied spectrophotometrically in the pH-controlled buffer solution over the temperature range from 10 to 50° C. The rate of the reaction is proportional to the concentrations of MMI and thiolate ion. For the reactions of MMI with CySH, PaSH and AeSH in a buffer solution of pH 7.0 and 30° C, the specific rate constants, km are 3.30 x 108, 7.59 x 104 and 1.10 x 107 dm mol-i, respectively. The activation entropies for the reaction in the pH region between 2.12 and 5.88 at 30° C have large negative values ranging from -99.5 to -152 J mol- These results suggest that the rate determining step is the nucleophilic addition of the thiolate ion to the double bond of MMI, and that the NH₃+ group of mercapto compound facilitates the reaction by assisting the polalization of the double bond of MMI and/or by lowering the energies of the transition state.

View full abstract

Catalytic hydrogenation of 1, 8-naphthalenedicarboximide [1 a] and 4-substituted-N-methyl1, 8-naphthalenedicarboximides [1 b-f] (X =H, OCH, , OH, NH, , SO₃Na) over palladium catalyst has been studied. First, [1 a] was hydrogenated (80° C and 50 kg/cm' of initial hydrogen pressure) to give 1, 2, 3, 4-tetrahydro-1, 8-naphthalenedicarboximide [2 a] (in 77% yield). The activity of palladium catalyst for the hydrogenation was higher than those of other plutinum group catalysts (Ru, Rh, and Pt). The hydrogenation of [1 a] under more drastic conditions (250° C and 50 kg/cm' of initial hydrogen pressure) gave decalin-1, 8-dicarboximide [ 3 ].
Next, [ 1 b-e] were hydrogenated (85, 225, 150, 220° C and 50, 80, 70, 80 kg/cm² of initial hydrogen pressure) to give the corresponding 5-substituted-. N-methyl-1, 2, 3, 4-tetrahydro-1, 8- naphthalenedicarboximides [2 ](in 60-80% yields). But[1 f] gave [1 b], because the ring hydrogenation did not occur under the same conditions.
Acetylation of [2 a] and [2b] with acetyl chloride gave 3-acetoxy-5, 6-dihydro-4 H-benz[de] isoquinolin-1-one [ 4 a] and 3-acetoxy-2-methyl-5, 6-dihydro-4 H-benz[de] isoquinolin-1-one [4 b], respectively.

View full abstract

The sulfonation of naphthalene with S03-base adducts was studied and the results are as follows;
(1) Reactivity of S03-base decreased in such a sequence as S03-dioxane>S03-DMF>SO, - pyridine>SO, -triethylamine. Sulfur trioxide-triethylamine did not react with naphthalene. (2) Sulfur trioxide-dioxane sulfonated naphthalene and gave mainly monosulfonic acid. The equimolar reaction of naphthalene and SO3-dioxane gave only monosulfonic acid. The composition of products in these reaction was almost invariable. In each case, 1-sulfonic acid formed in 90-83%. (3) Sulfur trioxide-DMF sulfonated naphthalene and gave mono and disulfonic acid. (4) Sulfur trioxide-pyridine sulfonated naphthalene at above 150° C to give a mixture of mono-, di- and trisulfonic acid. The reaction of naphthalene with four molar amounts of SO3-pyridine at 250° C gave 1, 3, 6-trisulfonic acid but mono- and disulfonic acids could not be detected. (5) When the reaction was carried out in organic solvents, a conversion of naphthalene and a ratio of disulfonic acids decreased in comparison with those under a solvent free conditions.

View full abstract

The interaction of sodium poly (styrenesulfonate) (PSSNa) with p-aminoazobenzene (D- I) or p-[bis (2-hydroxyethyl) amino]azobenzene (D-II) in aqueous solution has been studied. spectrophotometrically. The results showed the presence of two different bindings with equilibrium in each case; one was the electrostatic binding of PSSNa with the dyes protonated at 8-nitrogen of the azo group (complex 1) and the other was the binding of these dye molecules with the polymer in terms of a mechanism accompanying a change in electronic state of the dyes (complex 2) (Fig.1 and 5).
The binding constants, K, and K for complex 1 and 2, respectively, were calculated by the measurements of absorptivities at 510 and 460 nm for D- I SSNa system and 550 and 445 nm for D- II SSNa system (Eq. (7) and (5)). On the basis of the temperature dependence of K, change in enthalpy or in entropy of complex 2 formation has been evaluated as 11 2°=-0.9 ± 0.7 and 1.1 kcal/mol, and ZIS, °=-19.7 ± 2.5 and -19.2 e. u. for D- I and D- II at 25° C, respectively (Table 3 and 4). It was suggested that an increase in in solubilization of the dyes caused by PSSNa (4H°=-3.78 and -4.57 kcal/mol, and S°=5.6 and 17.3 e. u. for D- I and D- II at 25° C, respectively) (Table 3 and 5) involved the formations of complex 1 and 2.
The absorption, excitation, and emission spectra of sodium p-toluenesulfonate and PSSNa in aqueous solutions or in aqueous D- I solution (Fig.11) suggested that the bound dye interacted with benzene rings in the PSS side-chain and that mutual interaction among the side-chain benzene rings was enhanced with increasing concentration of the polymer in acetate buffer solution.

View full abstract

Catalytic gasification of polyethylene on silica-alumina supporting Ni, Pd or Pt, was carried out under a hydrogen atmosphere by a batch process. The effect of metal supported on silicaalumina on the yield of gas and the composition of gaseous products were examined at 300-600° C.
In the absence of the catalyst, the gasification proceeded rapidly at the temperature above 500° C, and at 600° C the yield of gas was 75 wt%. Ethylene, propylene and butenes constituted 70 wt% of the gaseous products. On the other hand, when silica-alumina supporting Ni was added in the proportion of 15 wt/ of polyethylene, the gasification was active at 350° C and the yield of gas increased rapidly with the increasing reaction temperature. Most of the gaseous products were butenes of which isobutylene was the main product.
When Ni was supported in the proportion of 0.2-0.4 wt% of silica-alumina and hydrogen was supplied in the proportion of 2.5 wt% of polyethylene, the yield of gas was 85 wt at 450° C. The composition of the gaseous products were nearly, constant even when the reaction temperature was raised and the relative amount of catalyst or the relative amount of supported Ni.

View full abstract

In a couse of studies on constituents of the cyperaceae, four kinds of essential oils obtained from roots of Kayatsurigusa, Cyperus microiria Steud.
collected in different seasons have been studied. The essential oils were separated into individual components by means of column chromatography and preparative gas chromatography (GC). Identification of known compounds were based on agreement of their tR in values and MS spectra with those of the authentic specimens, and structural determination of new compounds were performed on the ground of chemical and spectral evidence.
Thus, cyperene, caryophyllene, 8-cadinene, juniper camphor, a-cadinol, (2 E, 6 E)-farnesol, methyl (2 E, 6 E)-farnesate, methyl (2 E, 6 E, 9 Z)-3, 7, 11-trimethy1-2, 6, 9, 11-dodecatetraenoate [ 1 a], methyl (2 E, 6 E, 9 Z)-3, 7, 11-trimethy1-2, 6, 9, 11-dodecatetraenoate [1b], methyl (2 E, 6 E, 9 Z)-11-hydroxy-3, 7, 11-trimethy1-2, 6, 9-dodecatrienoate [ 2 ], and methyl (2 E, 6 E, 9 Z)- 11-hydroxy-3, 7, 11-trimethyl-2, 6, 9-dodecatrienoate [ 3 ] were identified as main components and a-copaene, x-humulene, a-elemene, 8-elemene and palustrol as minor ones.
The esters, [1 a], [ 1 b], [2], and [ 3] were new compounds.

View full abstract

In order to study the solution behavior of polyphosphate compounds, light scattering and viscosity measured were on the aqueous solution, with added sodium chloride, of ammonium polyphosphate prepared under the various polymerization conditions. The light scattering measurements were performed by a one-concentration method. The corrections for the degree of depolarization and the selective adsorption of low molecular weight ions on a polyphosphate ion were made to calculate the molecular weight of ammonium polyphosphate from light scattering data. The correction factor for the selective adsorption was calculated from the refractive index increment of the solution for light scattering and that of ammonium polyphosphate solution at Donnan's equilibrium with 0.1 moll aqueous sodium chloride solution. The solutions for light scattering and viscosity measurements were prepared from the same mother solution. The relationship between the molecular weight, M and intrinsic viscosity, [ r1], of the saline (0.1 mol/l sodium chloride) solution of ammonium polyphosphate was obtained for the molecular weight ranging from 49000 to 300000 at 25° C as [n]=8.26 x 10-5 mo.78.
The exponent in this relationship is not so much different from that of the most vinyl polymer solutions.
This suggests that the ammonium polyphosphate chain is a rather expanded random coil.

View full abstract

The polymerization of styrene in various solvents was carried out at 30° C, under irradiation with the light of wave length 366 nm and by using 1, 1' -azobiscyclohexanecarbonitrile (ACN) as a photo-sensitizer. The rate of polymerization (Rp) increased in the following order with respect to solvents: cyclohexane < benzene < 1, 2-dichloroethane < chlorobenzene < benzonitrile < bromobenzene < 1, 2, 4-trichlorobenzene < o-dichlorobenzene < benzyl alcohol.
The rate of initiation (R1) scarcely changed in these solvents, while the values of ktikp2 (=a) changed in them. The values of ktikp were obtained by means of rotating sector method, and the propagation rate constant (kp) and termination rate constant (kt) were derived on the basis of the values of kik, and ktIkp. The values of le, scarcely changed in these solvents, while those of kt markedly altered and were almost inversely proportional to the initial viscosity in this polymerization.

View full abstract

In order to disclose the possible interaction betWeen pollutants in waste water from different sources, the effect of pH on the turbidity of a starch solution was studied. The turbidity of the starch solution as a model of waste water from a desizing process decreased with the increase in pH of solution, and the reaction was irreversible under the experimental conditions (Fig.3).
The decrease in turbidity was caused solubilization of crude starch particle as a result of alkali sorption. The starch concentration, CT, in waste water was found to be given by equation:
where k2, k3, 1, m were constants (Table 2), T was the turbidity of starch solution, pK, was exponent of the ion product of water, and pH, was the pH value when the relation between turbidity and concentration on the starch solution was calculated.

View full abstract

The monoazo-type acid dyes have been oxidized by continuously supplying ozonized air in an aqueous solution (Fig.1). The decoloration rates of these reactions have been measured at 25° C (pH 7.0, : 0.2 (KNO₃)) (Table 2). The logarithms of the rate constants (log kobs) of these decoloration reactions increased linearly with increasing pH values of the solution between pH 5.5 and approximately half-neutralization points of the hydroxyl groups of these dyes (kobsocrOHla, a 0.13) (Fig.7). The linear relationship between the logarithms of the rate constants (log kobs) and the acid dissociation constants (pKoH) of these dyes can be derived by the following equation (Fig.9):
log kobs=-0.207 picOH +1.955 (25° C, pH 7.0, : 0.2 (KNO₃))
From these results, the mechanisms of these reactions seem to be nearly the same as that of ozone-olefin reactions proposed by Williamson and Cvetanovi6 (Scheme 1).

View full abstract

Chlorine atoms in polychlorinated biphenyls (PCB's, Kanechlor 400) were completely removed when PCB's were treated with Na-naphthalene [ 1 ] in THE for 10 min at 0° C (amount of Cl was less than 10-4 wt% after this treatment, Table 1). The minimum amount of [1] necessary to remove all chlorine atoms was estimated to be 1.1 mol/Cl when j was added to PCB's (inverse dropping), and 1.3 when PCB's were added to [ 1 ] (normal dropping) (Table 5). Even when the ratio of naphthalene to Na metal was reduced to 0.5, the dechlorination was completed within 5 hr (Table 3). K- and Li-naphthalene were also effective reductants. The average molecular weights of dechlorinated products were 400-600 (Table 7), which increased in the inverse dropping but decreased in the presence of proton sources. The dechlorination mechanism would be due to the two-step electron transfer, in which aryl anions are formed followed by S, 2-type arylations (Scheme 1); the arylation would be interfered with the protonation in the sterically unfavorable arylation processes or in the presence of alcohols. The present method seems to be useful for a facile and safe decomposition of PCB's when coupled with an ordinary incineration method.

View full abstract

Reactions betweem benzil and hydrogen in the presence of bis(diphenylglyoximato)cobalt (II)-pyridine complex were studied at 20° C under normal pressure. The reaction rate was not affected by the concentration of benzil (Fig.1), and the plot of the reaction rate vs. the concentration of the complex gave sigmoidal curves (Fig.2), and the addition of sodium hydroxide retarded the reaction (Fig.3). This alkali retardation contrasts strikingly. with alkali acceleration observed in the hydrogenation in the presence of bis(dimethylglyoximato) cobalt (II)-pyridine complex.

View full abstract

Effects of four different electron donors, i. e., tetrahydrofuran, dioxane, N, N-dimethylf ormamide, and dimethyl sulfoxide, on the dehydration of 2-methyl-2-butanol with antimony tribromide were examined. The participation order of these donors on the induction period of the dehydration was estimated to be roughly 0.4, while that on the over-all process of the dehydration ranged from 0.8 to 1.7 depending on the kind of donor added. On the basis of these results, the difference between the effect of the kinds of donor added on the induction period and the over-all process of dehydration is discussed.

View full abstract

The sulfonation of anthracene with SO₃-pyridine reported by Battegay was reinvestigated. Contrary with their results that 1-anthracenesulfonic acid was obtained in high selectivity, a mixture of six sulfonic acids was obtained 1- (14%), 2- (4%), 1, 5- (10%), 1, 8-(60%), 2, 6 +2, 7- (12%). The reaction in melting SO₃-pyridine gave 1-anthracenesulfonic acid in the selectivity of 40%.

View full abstract