A study on the frontier MO of benzoyloxyl radical was carried out by oh initio unrestricted HF MO (STO 3 G basis set) method. The following results were obtained: ( 1 ) The plane of phenyl group is orthogonal to the plane of carboxyl group. The optimized geometry can be seen from Fig.3 (in Text). ( 2 ) The carboxyl group has a Cs-²A' structure. Therefore the unpaired electron is of σ. From the calculation of gross orbital charges of the atoms of COO·, it was found that the α-spin density concentrates on ¹⁴C atom and exists on the plane of carboxyl group (Fig.4 in Text). ( 3 ) C₆H₅COO· has 63 electrons. Accordingly, the frontier MO are apparently ψ_α³² (abridged as α₃₂) and ψ_β³² (abridged as β₃₂). However, since α₃₂ and β₃₂ have different structures of a'' and a' concerning COO· structures, they are not a corresponding pair.
From the symmetries and the coefficients of 2 p orbitals, the pairs of αMO and βMO were identified from Fig.5 (in Text) as follows:
α₃₂-β₂₈;πMO of C₆H₅
α₃₁-β₂₉;πMO of C₆H₅
α₃₀-β₃₀;σMO of COO·, especially σ lone pair of O¹³
α₂₉-β₃₁;π lone pair of O¹⁴
α₂₈-β₂₇;σ HOMO of C₆H₅ by 2p_z orbitals
α₂₇-β₂₆;σ HOMO of C₆H₅COO· by 2p_y orbitals
α₂₆-β₂₅;πMO of C₆H₅
α₂₅-β₃₄;radical unpaired electron
Thus, α₂₅(-13.7228 eV) and β₃₄(+8.8294 eV ) were determined to be the radical MO of C₆H₅COO· as shown in Fig.6 (in Text).

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The electrochemical reactions of 0.03 mol·dm^-3 hydrogen peroxide in 6 mol·dm^-3 potassium hydroxide solution were investigated using the rotating ring-disc electrode (RRDE) of the well-processed glassy carbon (GC) and the Pt-supported GC disc electrodes. The theory for RRDE was applied to these circumstances. The heterogeneous reaction rate constants of electrochemical reduction and catalytic decomposition of hydrogen peroxide and their dependence on potential were evaluated from the results.
It is indicated that the value of the rest potential on the discelectrode is determined by the oxidation and reduction equilibrium of hydrogen peroxide.
The rate constants of catalytic decomposition scarcely depends on electrode potential, but the others depend on potential. The potential dependence of the rate constants of electrochemical reduction suggests that the influence of hydrogen peroxide on the electrode surface state plays an important role in determining the activity and stability of reaction sites.
The Pt-supported GC electrode showed the higher rate constants than that of the GC electrode. It was suggested that the chemical state of the electrode surface formed by the interaction between the supported Pt particles and the GC introduced the electrocatalytic activity and stability of the Pt-supported GC electrode.

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Poly(tetrafluoroethylene)(PTFE)-bonded carbon electrodes loaded with perovskite type oxides were investigated to develope high performance cathodes for electrochemical reduction of oxygen.
It was found that several oxides such as La_0.6Sr_0.4Fe_0.6M_0.4O₃ and La_0.8Sr_0.2 MO₃(M=Mn, Co) were quite active as electrode catalysts. The highest cathode performance was achieved with the electrode containing 40 wt% La_0.6Sr_0.4Fe_0.6M_0.4O₃ the current density as high as 1600 mA/cm², which was 15 times larger than that of a carbon electrode without the catalysts, was obtained at -125 mV vs. Hg/HgO (0.8 V vs. RHE) in 9 mol/dm³ NaOH at 80°C (Fig.7).
Based on the kinetic parameters collected by rotating ring-disk electrode measurements, it was deduced that the activation of the four-electron reduction of O₂ was most important as effective electrode catalysts. In addition, the ability to decompose HO₂- was considered to be necessary to obtain high current densities, because under such strongly polarized electrode potential, HO₂- can easily be produced on the carbon substrate or catalysts themselves. The electrode activity was stable in a short term operation for 50 h at the current density of 300 mA/cm² (Fig.8).

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Since hafnium belongs to the same group of elements as titanium and zirconium, SrHfO₃ may have photocatalytic activity comparable to those observed for SrTiO₃ and SrZrO₃. The band gap of SrHfO₃ is too large to be excited in the visible region of light. To improve this sulfurization-oxidation cyclic processings were tried. The sulfurization was made in CS2atmosphere (13.3 Pa) at 900°C, and then oxidation was made in O₂ atmosphere (0.1 MPa)at 600°C. The SrHfO₃ treated by three cyclic processings became to absorb visible light. The SrHfO₃ catalyst, thus prepared photolyzed H₂O-2-propanol and H₂O-methanol system with quantum efficiencies as high as 9.7%. Such visible light responsiveness may have been caused by the introduction of SO₂- ions during the CS₂-O₂ processing cycle.

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Ring opening of cyclohexane and methylcyclopentane (MCP) catalyzed by a cobalt-alumina catalyst was investigated at a hydrogen pressure of 10 kg/cm², in the temperature range from 230 to 300°C. MCP can react at a temperature by 30°C lower than cyclohexane (Fig.1). The major product from cyclohexane was methane with relatively small amount of C₂-C₆ normal and branched paraffins, MCP and benzene (Table 1). At lower temperature, the major products from MCP were methane and hexane isomers which consisted of hexane, 2-methylpentane (2-MP) and 3-methylpentane (3-MP). As the temperature increased, the selectivity for methane production increased (Table 3). The ratio of 3-MP with 2-MP in product was from 0.1 to 0.2 for cyclohexane reaction and 0.8 to 0.9 for MCP reaction (Tables 1, 3). The difference in the values between cyclohexane and MCP has been discussed in terms of the specific modes of their activated adsorption on the catalyst (Fig.2). It is suggested that the rate-determining step of hydrogenolysis of cyclohexane is dehydrogenation process to form activated adsorption species, and a reaction scheme for ring opening of cyclohexane is proposed (Fig.3).

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In relation to softening of city water, inhibition of boiler scale, retarding action on setting of gypsum hemihydrate and portland cement, several complexing agents such as sodium citrate, sucrose, α-D-glucose, diglycolic acid were chosen and the sequestration capacity of these agents and the composition of complex ions were studied by means of turbidometric titration, chelatometric titration, potentiometry using ion-selective electrode, electric conductivity for the purpose of forming the complex ions with calcium and magnesium ions in aqueous solution.
The se questration capacities of sodium citrate and saccharides differed considerably by the method of measurement. The reason was considered. The calcium ion was seauestrated very well by sodium citrate, the sequestration capacity toward calcium and magnesium ions being about 26.8 g and 17.0 g at pH 8.5, respectively. Most of the complex ions studied in the present work have the bonding ratio of 1/1 in terms of agent/calcium or magnesium, but the bonding ratio was 2/1 for diglycolic acid/calcium. A more stable complex ions appeared in the range of pH 8.0 to 9.5.

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The methanol solution of Co(dmgBF₂)₂ (the BF₂ capped species of bis(dimethylglyoximato)-cobalt(II) complex, Fig.1) containing a excess (with a mole ratio of about 1-6: 1) of tributylphosphine (P(n-C₄H₉)₃) was remarkably thermochromic. The solution which was purple at higher temperature than -20°C became blue at lower temperature than -40°C, and the color change was reversible. The thermal change of the visible absorption spectra of the solution, showed that the patterns of spectra at lower and higher temperatures are quite similar to those observed at higher and lower concentration ranges of tributhylphosphine. It is suggested from the visible absorption spectra and ESR spectra that the thermochromism of Co(dmgBF₂)₂-P(n-C₄H₉)₃-methanol solution is due to the shift of equiliblium between Co^II(dmgBF₂)₂·P(n-C₄H₉)₃ (purple) and Co^I(dmgBF₂)₂·P(n-C₄H₉)₃ (blue), and is th e same sort of change observed in varying concentrations of tributylphosphine.

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Conductometric titration of acid halides were examined by ethylenediaminetetraacetic acid (EDTA) in N, N-dimethylformamide (DMF). DMF was used as the solvent because the acid halide did not dissolve in water, but dissolved in the organic solvents such as DMF, dimethyl sulfoxide (DMSO), pyridine, etc., while EDTA could dissolve in DMF only. The acid halides used therein were butyryl chloride, octanoyl chloride, palmitoyl chloride and acetyl halide. Standerdization of the solutions was made by gravimetry.
After the sample solution was taken in the titration cell, DMF was added and they were stirred and titrated. Titration was carried out at the speed from 0.5 cm³·min^-1 to 1.0 cm³·min^-1 at room temperature. The observed molar ratio between the chlorides and EDTA w as found to be 1: 1. The significant inflection point was not obtained by the use of other solvents (DMSO, pyridine, etc. ).
Less than 1 v/v% of water gave no influence on this method, but the equivalent molar of various metal ions such as Ni²⁺, Cu²⁺, Co²⁺, etc., gave a posxitive error respectively.
The total of 1 × 10^-2 mol·dm^-3 of chloride and acid halides was obtained. The applicable concentration range of the method was from about 1 × 10^-3 mol·dm^-3 to 5 × 10^-2 mol·dm^-3.
It seemed that these reactions were addition reactions for nitrogen atom of EDTA. These reactions seemed to depend on length of the ionic radius and electronegativity, but did not relate to dissociation energy between carbon and the halogen atom.

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Several 2-substituted 4, 6-diphenyl-1, 3-thiazin-l-ium salts were accessible conveniently by the reaction of benzoylphenylacetylene with thioamides in the presence of a strong acid. The reactivity of 2-methylthio-4, 6-diphenyl-1, 3-thiazin-l-ium perchlorate (1a) toward nucleophiles, such as active methylenes and various amino compounds, was investigated. Active methylenes and monofunctional primary amines attacked the 2-position of the thiazinium ring to afford 2-(disubstituted methylene)- and 2-(substituted imino)-4, 6-diphenyl-2 H-1, 3thiazines, respectively.
On the o ther hand, bifunctional nucleophiles, such as hydrazine and hydroxylamine, reacted at the 4-and 6-positions of (1a) to give 3, 5-diphenylpyrazole and isoxazole, respectively.

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The reaction of 3-aryl-5-phenyl-2-isoxazoline [15] with [Mo(CO)₆] (Equation ( 5 ), Table 1) follows two pathways both via an intermediate of the pentacarbonyl(2-isoxazoline-N)molybdenum ( 0 ) species [21] (Scheme 1). One includes the N-O bond cleavage and subsequent reactions to result in the formation of 1-aryl-3-phenyl-1-propanone [17], 1-ary1-3pheny1-2-propen-1-one [18], and 1, 3-diary1-5, 8-diphenyl-2, 6-diazabicyclo[2.2.2]oct-3-ene [19]. The other pathway includes the N-O and C4-C 5 bond cleavages to give benzaldehyde [20] and (1-arylvinyl) nitrene complex [2]. The reduction-hydrolysis and dimerization of [2] give acetophenone derivative [4] and 2, 5-diarylpyrrole [3], respectively. Furthermore, [2] undergoes novel cyclocondensation with 1-aryl-3-phenyl-2-propen-1-one [18] to give 2, 6-diaryl-4-phenylpyridine [16] (Scheme 2). Evidence for the mechanistic aspect of the formation of the pyridine is obtained by the studies on the [Mo(CO)₆]-induced reaction of a-azidostyrene [1a] with α, β-unsaturated ketones [18a] and [18c-d] (Table 2). The reaction of 3-hydroxy-1, 3-diphenyl-1-propanone oxime [35] with [Mo(CO)₆] was also found to give 2, 4, 6-triphe nylpyridine [16a] in a similar manner (Equations ( 6 ) and ( 7 )).

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Oxidation of secondary alcohols with sodium bromite (NaBrO₂) was studied in the alkaline aqueous solution.
The ox idation proceeded effectively and stoichiometrically at room temperature in the presence of a small amount of metal powders or ions such as Cu, Cu²⁺, Ru³⁺, or Al³⁺. No oxidation occurred without the metal ions. While secondary monohydric alcohols gave ketones in high yield, diols gave diketones, keto alcohols and/or enones depending on the structure of alcohols, and sodium bromide was the final inorganic product.
Thus, NaBrO₂ is a valuable oxidizing agent for alcohols, and its oxidati on capability in the alkaline aqueous solution can be considered to be superior to Fetizon's reagent.

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The reactions of anthrone with group 5B metal amides (R₂N)₃M(M=As and Sb) at 140°C for several days afforded the substitution products: bis(9-anthryloxy)(dialkylamino)arsine and -stibine. On the other hand, group 4B metal amides (R₂N)₄M(M=Si, Ge and Sn)reacted with anthrone to give 9-(dialkylarnino)anthracene along with the substitution products: bis(9-anthryloxy)bis(dialkylamino)metals. Transition metal amides of group 4 (Ti and Zr) and 5 (V and Nb) reacted with anthrone to give only 9-(dialkylamino)anthracene. The reaction of tetrakis(alkylthio)silane and -stanane with anthrone gave both 9-(alkylthio)anthracene and anthracene, whereas tris(alkylthio)arsine and -stibine gave anthracene only. Possible reaction mechanisms were proposed.

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The Reactions of anthrone with group 4B metal alkoxides (RO)₄M (M=Ge and Sn) at 140°C for a week provided 10-alkylanthrone, which were considered to be rearrangement products from the substituted intermediates ; dialkoxybis(9-anthryloxy)metals. On the other hand, group 4A and 5A metal alkoxides (RO)₄M (M=Ti and Zr), O=V(RO)₃ and (RO)₅Nb reacted with anthrone at 140°C for 24 h to give the substituted intermediates. And these unstable intermediates decomposed giving anthracene and 9, 10-dihydroanthracene. In these cases, Meerwein type reduction of 9-anthryloxy group might provide anthracene, and following redution of anthracene gave 9, 10-dihydroanthracene.

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The isomerization of 1, 5-cyclooctadiene(1, 5-COD) in the presence of catalytic amount of Ni(acac)₂-Et₃Al₂Cl₃-phosphorus ligand(Ni: Al₂=1: 10 molar ratio) was investigated. Wit h added PPh₃/Ni=0-3, 1, 5-COD isomerized rapidly at 10-60°C in toluene to give bicy clo[3.3.0]oct-2-ene(BCO, transannular product) in high selectivities (90%-) with 1, 4- and 1, 3-COD(double-bond isomerization products) in trace amounts. With PPh₃/Ni=6-10, the isomerization was slow, but the double-bond isomerization products were obtained in fairly high selectivities (Table 1). By comparison of 17 kinds of phosphorus ligands, the electronic effect of the ligands was observed for the isomerization: The reaction rate and the doublebond isomerization products increased with a decrease in the electron-donating ability of the ligands. With certain phosphite, 1, 4-COD was produced as a main product (selectivity 70%-). On the other hand, the steric effect was not appreciable (Table 2).
The overall rate of formation of BCO can be represented by the form: R=k[Ni]₀[1, 5COD]/(K+ [1, 5-COD]), k≈ 10^13.6exp(-16300/RT) min^-1, K=0.252 mol·l^-3(10°C), where [Ni]₀ is the concentration of Ni(acac)₂ used. The activation parameters are ΔH=15.7 kcal·mol^-1 and ΔS= 6.6 cal·deg^-1mol^-1. A reaction mechanism, in which hydridonickel complexes are considered to be the active species, is proposed for the isomerization to account for the experimental results.

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Effects of luminescence species adsorbed from ambient atmosphere and model compounds of polynuclear aromatic compounds (PNA) assumed to be the luminescence species on the photodegradation of high density polyethylene (HDPE) were examined. Furthermore, effects of precipitates extracted from HDPE and their model compounds, i. e.3-octanone and 1icosene were also investigated. The results obtained were as follows:
The luminescence species adsorbed under normal atmospheric cond itions and equivalent amount of PNA did not affect the photodegradation of HDPE. On the other hand, the extracted precipitates accelerated the photodegradation of HDPE and 3-octanone slightly accelerated it, but little effect was observed in 1-icosene. The results suggest that impurity components other than luminescence species such as PNA and extracted precipitate components containing carbonyl and terminal unsaturation groups play very important role in the photodegradation of HDPE. Therefore, affecting order of the impurities on the photodegradation of HDPE is as follows:
Extracted precipitates> >>C=O > PNA -CH=CH₂

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Electrodeposition of silver-palladium alloy from cyanide solutions with addition of NaAsO₂ has been investigated. It was found that the arsenic ions have marked effects that made deposition potentials of silver, palladium and silver-palladium alloy more noble and limiting current higher. The silver-palladium alloy appears to be deposited under the diffusion control of silver ions. Palladium content in the alloy tended to increase with an increase of NaAsO₂ or palladium content in electrolytes and decreased with an increase of solution temperature. Further, a decrease in the current density or an increase in the magnitude of stirring yielded alloy coatings with lower palladium content. The cathode current efficiency was found to be lowered, at a high current density by the evolution of hydrogen. SEM photographs showed that crystal grains became globular as the current density was enhanced, and alloy films with less than 10% palladium had smooth and fine surfaces.

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The catalytic dehydrogenation of butanols over the silica-copper(II) and -zinc(II), which were prepared by the precipitation method from homogeneous solution at pH 8, was compared with those of the catalysts prepared by usual coprecipitation method. Dehydrogenation took place selectively over the catalysts prepared by both methods. The catalytic dehydrogenation activities on the homogeneous catalysts were much higher than those on the coprecipitated catalysts, and the order of activity was Cu(II)>Zn(II), and 1-butanol>2-methyl-l-propanol>2-butanol.
Kinetic studies using a flow reactor indicated that the dehydrogenation was of first-order irreversible reaction. From the Arrhenius plots the activation energies for the dehydrogenation of 1-butanol, 2-methyl-1-propanol and 2-butanol over the homogeneous silica-copper(II)were found to be 12.1, 16.0 and 41.2 kcal/mol·g, respectively.

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The catalytic hydrogenolysis of cyclopropylamine [1] was studied in order to investigate the regioselective behavior of the amino group in the cyclopropane ring hydrogenolysis. The reaction was carried out over Pd-C or Raney Ni in heptane or methanol for 24 h at room temperature under the atmospheric pressure or at 70°C under 80 kg/cm². The hydrogenolysis of the cyclopropane ring occurred selectively at the bond adjacent to the amino group and gave propylamine [4], accompanying dipropylamine [5], N-propylcyclopropylamine [6]and tripropylamine [7] formed by the subsequent reductive alkylation. The reductive alkylation proceeded more easily by the use of Pd-C than by Raney Ni. On the other hand, when the reaction was carried out over Pd-C in CH₃COOH or H₂O containing HC1 in equimolar amounts to [1], the hydrogenolysis occurred mainly at the bond opposite to the amino group and gave mainly isopropylamine [3].
The observed differences seem to be ex plained by considering the predominant adsorbed states in the hydrogenolysis. The amino group behaves as an adsorbed group and causing the adsorption and the subsequent cleavage of the adjacent C₁-C₂ bond under the neutral conditions. On the other hand, under the acidic conditions, the hydrogenolysis of the opposite C₂-C₃ bond proceeds predominantly because the adsorption of the C₁-C₂ bond accompanying the ammonio group is sterically hindered by the ammonio group.

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Metal alkoxides such as titanium and zirconium tetraisopropoxide and tetraethoxysilane reacted with 2-hydroxy-4 (or 5)-X-substituted aniline (X=H, CH₃, NO₂) and salicylaldehyde or 2-hydroxy-l-naphthaldehyde to give metal(W) complexes of Schiff bases in excellent yields. The reaction provides a simple method for the preparation of these metal complexes without using Schiff bases.

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The stereoselectivity in the rhodium(I)-catalyzed reduction of 2-alkyl-substituted cyclopentanones and cyclohexanones with organosilanes was investigated. Relative amount of the more stable alcohol increased with bulkiness of organosilanes used, and the more bulkiness of 2-alkyl substituents produced the larger percentage of less stable of the two possible alcohols. The results were compared with those of the reduction by boranes and those of hydrogenation over platinum catalyst.

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