From the measurements of polarized absorption spectra using stretched PVA films and from the polarization of the electronic transitions of coumarin and its 4- and 7-hydroxy derivatives were determined. It has been clarified that in each compound the first and second bands are polarized along the longer molecular-axis and the third one is almost perpendicular to it. These results were well interpreted in terms of the configuration analysis.

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Yellow iron oxide (α-Fe0OH) was synthesized by the seed method and then autoclaved it in 1 N NaOH solution at 200°C for 5 hr.
The effects of the hydrothermal treatment on the powder properties, thermal decomposition process, and grinding change of the iron oxide, were investigated by electronmicroscopic observation, X-ray diffraction, DTA, and specific surface area measurements.
The following results were obtained:
( 1 ) By the electronmicroscopic observation, needle-like particles of α-FeOOH were transformed into rod-like particles and the size distribution was substantially homogenized by the hydrothermal treatment. The specific surface area was reduced to about one third its initial one and the X-ray diffraction peaks became sharp. From these facts, in terms of the reaction in an autoclave, the fine particles and the ends of needle-like particles, present in untreated α-FeOOH, dissolved and then changed into particles of a suitable size.
( 2 ) Added clearness to the coloring and the resistance to grinding were increased.
(3) The thermal stability was also improved by the hydrothermal treatment. For example, the treated α-FeOOH decomposed to α-Fe₂O₃ at above 260°C, while the untreated one did at lower temperatures, 220∼250°C, with two steps.

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Studies were made on the relation between adhesion and surface properties for pretreated polyethylene, Teflon, and poly (ethylene terephthalate) samples. Pretreatments made were immersion in chromic acid mixtures, ultraviolet irradiation, electron bombardment under reduced pressure, and oxidation with flame of town gas for polyethylene, electron bombardment for Teflon and ultraviolet irradiation and chemical etchings for poly (ethylene terephthalate). The mechanism for the increase of adhesion strength due to the treatments was discussed with data of the critical surface tension and the adhesion tension for various liquids in air and in water. It is likely that hydrogen bond like interaction between adhesives and polar groups formed on the surface in the above-mentioned treatments causes the increase of adhesion strength.

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The adsorption of SO₂ on iron(III) hydroxide oxides(iron(III) oxyhydroxides)(α-FeOOH, β-FeOOH, and γ-FeOOH) prepared from various mixed solutions of Fe(II or III), Mg(II), Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) (0∼50 metal/Fe atomic%), has been investigated by the X-ray diffraction, surface area measurement, and chemical analysis. Results showed that the metal ions added impede the crystal growth of α-FeOOH and γ-FeOOH, but promote the formation of spinet. For α-Fe0OH, the maximum amount of chemisorption of SO₂ appeared on the samples containing each ion of ca.5 atomic%, except Mn (II)-doped samples which showed high SO₂ chemisorption capacity (0.51∼0.59 mg/m²) in the range of Mn(II) content over 25 atomic%. The β-FeOOH doped with 5.2 atomic% Cu(II) chernisorbed a considerably large amount of SO₂ (0.81 mg/m²). Whilst the SO₂ chemisorption on γ-FeOOH did not vary markedly with the Cu(II) content in the range of 0∼48.2 atomic%. The SO₂ chemisorption capacity of γ-FeOOH was decreased in general by the addition of foreign ions, except Cu(II), although their incorporations were limited in a range up to 9.2 atomic.

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For the improvement of the capacity of a silver-silver oxide electrode as a positive plate of an alkaline battery, the effects of addition of thallium, lead, and indium salts to the electrolyte on the behavior of the silver-silver oxide electrode were investigated.
The following results were obtained:
1) The capacity during charge and discharge was increased by the addition of thallium, lead or indium salts. Especially, the addition of an indium salt was effective. An intermediate small potential maximum in the 1 st stage of charging disappeared by the addition of a thallium or lead salt.
2) All peaks in the cyclic voltammetry became larger by the addition of thallium, lead, and indium salts even in the first cycle. An increase of active materials at the silver-silver oxide electrode was found.
3) Results of charge-discharge curves, current-potential curves, observations with an electron microscope, and fluorescence X-ray analysis showed that fine-grained crystals of active materials were formed by the electrolytic deposition in the case of thallium, by the electrolytic deposition and adsorption in the case of lead, and by adsorption in the case of indium; and therefore, the addition of these metallic salts were effective.

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The conditions of the formation of NdPO₄.0.5 H₂O, NdPO₄, Nd(PO₃)₃ and NdP₅O₁₄ in the reaction of neodymium oxide with orthophosphoric acid have been investigated, and their compositions, infrared absorption spectra and thermal change are presented. Neodymium orthophosphate NdPO₄.0.5 H₂O can be easily formed at an atomic ratio P/Nd (R)=1 and a low temperature below 500°C, while NdPO₄ at R=1 and 500∼800°C. On the other hand, Nd(PO₃)₃ can be purely prepared under conditions R=3 and >500°C/or Raw and heating at 300°C for 20 hr. Neodymium ultraphosphate NdP₅O₁₄ can be purely prepared at R 10 and by heating at a temperature above 500°C. Further, NdPO₄.0.5 H₂O and Nd₄(P₄O₁₂)₃.13H₂O can be easily obtained in crystalline form by reaction in aqueous solution. From the fact that chemical and fluorescent X-ray analyses of NdPO₄.0.5 H₂O, NdPO₄, Nd(PO₃)₃, Nd₄(P₄O₁₂)₃.13H₂O and NdP₅O₁₄ samples agree well with calculated values, chemical formulas of these compounds are proved to be right.
Neodymium orthophosphate NdPO₄.0.5 H₂O (hexagonal) is changed at about 210°C into NdPO₄(hexagonal), which, on heation at a temperature above 600°C, is gradually transformed into NdPO₄(monoclinic). On the other hand, Nd₄(P₄O₁₂)₃.13H₂O loses 7.5 H₂O at 100°C, and the remaining water of crystallization completely at 160°C to form amorphous substance. This amorphous substance is changed into an unknown substance at 670∼700°C and then into Nd(PO₃)₃ at 830°C. When NdP₅O₁₄ is heated at a temperature above 1000°C, it is decomposed into Nd(P0₃)₃, with the evolution of P₂O₅ fumes. Neodymium metaphosphate Nd(PO₃)₃, though stable up to about 1100°C, melts at 1200°C.

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An ilmenite type compound or an anatase type product, obtained from ilmenite treated with sulfuric acid, was allowed to react with NaOH in the mole ratio Na₂O/TiO₃ of 0.44∼1.10 at temperature of 110∼500°C. Crystalline fractions in the sample decreased with increase in the mole ratio and reaction temperature and sodium titanate was found in the product at the mole ratio of 0.64 or more. The resulting product was easily hydrolyzed in water, giving an amorphous substance which was soluble in diluted sulfuric acid.
Some impurities in the sample, such as chromium and vanadium, were converted into water-soluble form by the alkali treatment, so that more than 90% of these ions could be removed.

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Properties of α, β, γ, δ-tetrakis (4-carboxyphenyl) porphine [T(4-CP)P] and its complex f ormation with metal ions have been studied in aqueous sodium dodecyl sulfate solution. A highly sensitive and selective method for the determination of copper at ppb level has been established using the Soret band of the copper (II)-T (4-CP)P complex. The complex formation of copper(II) with T (4-CP)P is slow at room temperature. However, it proceeds quantitatively at pH about 5.5, the solution being heated at about 100°C for 5 min in the presence of small amounts of hydroxylamine. The Soret band of the complex lay at 416 nm, which was well separated from that of diacid form of T (4-CP)P (440 nm). A straight line calibration curve was obtained up to at least 140 ppb of copper. Apparent molar absorption coefficient of the complex and sensitivity for 0.001 absorbance were 4.2 × 10⁵l. mol^-1 cm^-1 and 0.15 ng Cu.cm^-2, respectively. Tolerance limits were shown for 17 ions and 16 salts. The method established could be applied to the determination of copper in water boiled in a kettle with satisfactory results.

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Chemiluminescent detector(CLD) was used to detect sulfur compounds, nitrogen compounds and carbon compounds in gas chromatographic effluent. Atomic oxygen was produced by the dissociation of molecular oxygen in the microwave discharge and chemiluminescence emitted - through the reaction of the mentioned compounds with atomic oxygen was detected by photo multiplier at 300, 310 and 610 nm by the use of interference filters, respectively. Detection limit of CLD for sulfur compounds and carbon compounds were comparable to that of FPD and TCD.
CLD was fifth times less sensitive than FPD for the detection of H₂S and eight times more sensitive than TCD for the detection of C₂H₄. CLD was found to be suitable detector for gas chromatographic detection of sulfur compounds and nitrogen compounds.

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A new spectrophotometric method has been developed for the determination of micro amounts of mercury (II). The method is based on the formation of tricyanomercurate(II) by the reaction of mercury(II) with cyanides, and on the extraction of the cyanomercurate into 1, 2-dichloroethane as an ion-pair with Methylene Blue. A recommended procedure is as follows. Put 10 ml of a sample solution containing mercury up to 20, μg in a 50 ml separatory funnel, and add 2 ml of a phosphate buffer solution (pH 7.0) and 2 ml of 3 × 10^-2mol/l potassium cyanide. To this mixture, add 1 ml of 1.5 × 10^-3 mol/l Methylene Blue and 10 ml of 1, 2- dichloroethane, and shake the funnel for 1 min. After standing for a given period of time, transfer the organic phase to a 15 ml glass tube with a stopper, and add a small amount of anhydrous sodium sulfate. Shake the mixture vigorously by hand until the phase becomes transparent, and measure the absorbance at 657 nm against dichloroethane.
The extract has a maximum absorption at 657 nm, and gives the maximal and constant absorbances in the pH range 7.7∼8.0. The calibration line (symbol O) in Fig.3, obtained by the above recommended procedure, is straight up to 20 pg mercury. The color of the extract is very stable; no measurable change in absorbance was found even after standing for 3 days at room temperature. The apparent molar absorptivity of the extract at 657 nm is 9.02 × 10⁴ cm^-1.mol^-1. l and its Sandell sensitivity is 2.2 × 10^-3 μg Hg.cm^-2for absorbance= 0.001. In six results for 10 ml aliquot of 6 × 10^-3 mol/l mercury solution (12 μg Hg), the the present method gave a mean absorbance value of 0.541, with a standard deviation of 0.002 absorbance unit and a relative standard deviation of 0.4%. Composition of extracted species and its percent extraction were respectively evaluated.

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The electrochemical reduction of pyrimidine and quinazoline was investigated at a mercury electrode in N, N-dimethylf ormamide(DMF)-water and aqueous buffer solution. The electrode reaction mechanism of quinazoline in DMF-water was found to be nearly similar to those of pyrimidine except that pyrimidine showed the only 1-electron wave at 0. 1 vol% H₂O. A series of experimental data suggest the following mechanisms for the electrode reaction of pyrimidine and quinazoline in DMF-water and buffer solution.
These mechanisms were supported by controlled potential coulometry and the UV spectra of the solution obtained after controlled potential electrolysis.

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Ortho-, pyro- and triphoshate in detergents were separated by a column packed with a porous micro-spherical strong anion exchanger (TSK-Gel LS-222, 6 μm) and the condensed phosphates in the column effluent were determined calorimetrically by the post-column method. Color-producing agent, consisted of nitric acid, ammonium molybdate and metavanadate, was mixed continuously with the column effluent. The condensed phosphates were hydrolyzed by the acid and the yellow complex of phosphate, molybdate and vanadate was formed in the acid solution. The absorbance of the solution was monitored spectrophotometrically at 400 nm using a micro flow cell. The separation of the condensed phosphates was affected by the pH and concentration of potassium chloride in the eluent, as shown in Figs.2 and 3. The sensitivity of the detection was influenced by the concentration of nitric acid, ammonium molybdate and metavanadate in the color-producing agent (Figs.4, 5 and 6) and temperature of the reaction bath (Fig.7). The recommended conditions for the analysis were as follows; analytical column: 5 mm I. D. × 50 mm, eluent: pH 9.2, (0.005 mol/l sodium borate-0.23 mol/l potassium chloride containing 0.1% EDTA-2 Na), analytical column temperature: 35°C, color-producing agent: 2.5 mol/l nitric acid containing 0.8% ammonium molybdate and 0.02% ammonium metavanadate, flow rate eluent 0.8 ml/min and color-producing agent 0.4 ml/min, reaction coil: 0.5, mm I. D.× 10 m, reaction bath temperature: 120°C. Synthetic mixtures of the condensed phosphates were analyzed by the proposed condition. The ratio of peak area obtained in the chromatograms agreed with the P₂O₃, ratio of the mixtures (Table 1). The calibration curve for orthophosphate was linear over the range of 0.75∼3.0 μg, pyrophosphate was 1.0∼4.0 μg and triphosphate was 1.5∼6.0μg, as shown in Fig.8. The calibration curve for pyrophosphate was parallel to that for triphosphate, but that for orthophosphate was deviated slightly from this relationship. However, this deviation was negligible as orthophosphate was a minor component in detergents. Since the slope of those for pyro- and triphosphate was identical, total P₂O₃, content in detergents was obtained with that for triphosphate and the sum of the peak area of each phosphate species. The condensed phosphates in commercial detergents were separated completely without any interference and the total P₂O₃ contents obtained by the proposed method agreed with those obtained by the Auto-Analyzer method, as shown in Table 2.

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The difference in the strength of hydrogen bond between oxygen-containing heterocyclic hydroperoxides (2-tetrahydropyranyl hydroperoxide, 1, 4-dioxan-2-yl hydroperoxide and 2-tetra- hydrofuryl hydroperoxide) and cycloalkyl hydroperoxides (cyclohexyl hydroperoxide and cyclo- pentyl hydroperoxide) was studied by means of IR and NMR spectroscopies, and the reasons for the strength of the stronger association of the oxygen-containing heterocyclic hydroper- oxides were discussed.
The bonded OH band of the heterocyclic hydroperoxides was observed even in low concentration and was little affected from carbon tetrachloride to chloroform or benzene by varing the solvent. The large wave number shifts from the free OH band (Δv 160∼490 cm^-1) indicated the strong interaction of hydrogen bond. The dependence on the concentration was observed in the spectra and the axial orientation of hydroperoxyl group does not allow the interaction between the proton of hydroperoxyl group and the unshared electron of the ring oxygen, so that the heterocyclic hydroperoxides show no intramolecular hydrogen bond. The large down field shift (δ=8.55 ppm) of the signal of hydroperoxyl proton suggests that the proton is more acidic.
Consequently, the association structure of the heterocyclic hydroperoxides is similar to that of the alicyclic hydroperoxides, but the inductive effect of a-oxygen atom in the ring is acted greatly in the intermolecular hydrogen bond.

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A marked induction period was observed in the first stage of dehydration reaction of 2-methyl-2-butanol with anhydrous antimony tribromide. The length of induction period was found to be exponentially reduced with increasing concentration of the Lewis acid. Plots of logarithms of the concentration of the Lewis acid against those of reciprocal of induction period values ((IP)^-1) were found to be linear with a positive slope. From the slope of the line, this reaction was of the first-order with respect to antimony tribromide approximately. Further, the length of induction period was markedly affected by hydrogen bromide evolved during the dehydration proceeded. Accordingly, induction period was markedly reduced or entirely distinguished by the addition of hydrogen bromide to the reaction mixture. However, the marked reduction of induction period showed the necessity of the Lewis acid catalyst besides hydrogen bromide. Arrhenius plots were found to be linear.
The activation energy of the process of induction period was estimated to be 8∼11kcal/mol, which is about a half of that of the dehydration under similar conditions. These observations suggested that induction period of the reaction was considered to be the time required for a sufficient accumulation of hydrogen bromide formed from the alcohol-catalyst complex to initiate the reaction.

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The thermal rearrangement of N- (substituted allyl)-N-tosyl-1-naphthylamines containing 1-methyl [1 a], 2-methyl [1 b], 3-methyl [1 c], 3, 3-dimethyl [1 d], or 3-phenyl group [1 e] as a substituent on the allyl group was examined. The starting compounds except [1 d] gave expected 2- (inverted ally1)-N-tosyl-1-naphthylamines ([2 a], [2 b], [2 c], and [2 e] respectively), the formation of which demonstrates that the ortho rearrangement involves a [3, 3] sigmatropic rearrangement.
Furthermore, 4- (non-inverted allyl)-N-tosyl-1-naphthyl-amines ([4 c], [4 d] and [4e]) were obtained only from the starting compounds containing substituents in 3-position of the allyl group ([1 c], [1 d] and [1 e]). The p/o ratios in each products increased in the following rder; [4 c] < [4 e] < [4 d], and [4 d] was a sole product from [1 d]. These results show that the para rearrangement involves successive [3, 3]sigmatropic rearrangements, followed by the enamidation (Fig.3). The driving force of the para rearrangement is the steric interaction between the tosylimino group and the 1-position substituted allyl group, formed by inversion of the ortho rearranged intermediate (A).

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The cyclocotrimerization of acetylenes with isocyanates in the presence of (η⁵-cyclopentadienyl) (triphenylphosphine) cobaltacyclopentadiene [ 1 ] or bis (η⁵-cyclopentadienyl) cobalt (II) (6) gave various 2-oxo-1, 2-dihydropyridines in good yields. For example, when a mixture of methyl phenylpropiolate [2 a], phenyl isocyanate [3 a], and a catalytic amount of [1 a] was heated at 135°C for 19 hr, dimethyl 1, 3, 6-triphenyl-2-oxo-1, 2-dihydropyridine-4, 5-dicarboxylate [4 a] and dimethyl 1, 4, 6-triphenyl-2-oxo-1, 2-dihydropyridine-3, 5-dicarboxylate [5 a] were obtained in 40 and 26% yields, respectively. The cyclocotrimerization of isocyanates with terminal acetylenes such as phenylacetylene [2 b], propyne [2 c], and 1-hexyne (2 d) also yielded two cotrimers, 1, 3, 6-and 1, 4, titrisubstituted 2-oxo-1, 2-dihydropyridines.
Similarly, the cyclocotrimerization of asymmetric acetylenes with diphenylcarbodiimide gave two 2-irnino-1, 2-dihydropyridines isomers. An attempt to obtain 2-thioxo-1, 2-dihydropyridine from [ 2 a ], and phenyl isothiocyanate [10] was unsuccessful because of a desulfurization of [10], but gave 2-irnino-5-thioxo--3-pyrroline [11] which might be derived from [2 a], [10], and phenyl isocyanide, the desulfurized product of [10].
A mechanism of the cyclocotrimerization of acetylenes with the heterocumulenes was discussed.

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The reaction of methyl propiolate [ 1 ] with isocyanates [ 2 ] in the presence of bis (η⁵-cyclopentadienyl) cobalt ( II ) [ 3 ] or (η⁵-cyanomethylcyclopentadiene) (η⁵-cyclopentadienyl) cobalt ( I ) [10] gave a mixture of geometrical isomers of the 1: 2 cyclocotrimers, 1, 3-disubstituted 5- (methoxycarbonylmethylene) hydantoins [ 4 ](Z) and [ 5 ](E), which structures were charac- terized on the basis of their chemical reactivities and their NMR spectra.
The isomer ratio depended on both the reaction temperature and the catalytic concentration; the ratio of [ 4 ] increased at higher temperature and at higher concentration of the catalysts. When the isomer [5c] (R=Ph) was heated at 125°C for 5 hr in the presence of [3], a mixture of [14 c] and [5 c] in a ratio of 4: 1 was obtained. From these results we concluded that in the cyclocotrimerization the E-isomer [ 5 ] is a kinetically controlled product and the more thermodynamically stable Z-isomer [ 4 ] is generated by an isomerization of the former. A mechanism of the cyclocotrimerization was shown in Scheme; the oxidative addition of [1] to a low valent cobalt complex results in the formation of a cobalt acetylide bond, into which two molecules of [2] insert stepwisely to give [13]. The linear intermediate [13] induces an intramolecular addition of the cobalt-nitrogen bond to the acetylenic bond to form a cyclization product [14], which gives hydrantion [5] by the subsequent reductive elimination.

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In the present study the relative catalytic activity with respect to the various types of condensation of aliphatic aldehydes, RCH₂CHO (R=H, Me and Et), has been investigated utilizing a number of metal(W) alkoxides, M(OR')₄(M=Ti, Zr, Hf, Si, Ge, Sn and R'=^tPr, ^tBu).
Ti-, Zr- and Hf-alkoxides led to the formation of trimeric glycol esters, RCH₂CH(OH)CH(R)CH₂OCOCH₂R, in preferrence to the simple esters, RCH₂COOCH₂CH₂R, which were obtained mainly in the condensation reaction of aldehydes in the presence of Al-alkoxide.Si-, Ge- and Sn-alkoxides produced mainly dehydrated aldol-type condensation products, RCH₂CH=C(R)CHO, from aldehydes.The formation of the glycol esters has been attributed to a bifunctional activity of the catalyst whlch results in an aldol-type condensation followed by a crossed ester condensation between the aldol-type compound and the original aldehyde.

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The demethylation reaction of 6-hydroxy-5, 7-dimethoxyflavones [2] with anhydrous aluminum chloride in acetonitril was studied. It was found that methoxyl groups on the ring A of 6-hydroxy-5, 7, 4'-trimethoxyflavone [2a] were selectively split up to give a mixture of 5, 6- dihydroxy-7, 4'-dimethoxyflavone [3a] and 5, 6, 7-trihydroxy-4'-methoxyflavone [1a] as main products. Monoacetate of [3a] and triacetate of [1a] were easily separated by the mild acetylation of the mixture with acetic anhydride-pyridine.
This selective demethylation reaction was available for the synthesis of 5, 6, 7-trihydroxyflavones [1] which have some methoxyl substituents on the ring B of flavones. By this method, 5, 6, 7-trihydroxy-4'-methoxyflavone (scutellarein 4'-methyl ether) [1a], 5, 6, 7, 4'-tetrahydroxyflavone [1b], 5, 6, 7-trihydroxy-3', 4'-dimethoxyflavone [1c], 5, 6, 7, 4'-tetrahydroxy-3'-methoxyflavone (nordifloretin) [1d], 5, 6, 7, 3', 4'-pentahydroxyflavone [1e], and 5, 6, 7-trihydroxy3', 4', 5'-trimethoxyflavone [1f] were synthesized from the corresponding 6-hydroxy-5, 7-dimethoxyflavones [2].

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Transesterifications of dimethyl terephthalate (DMT) with α-hydro-ω-hydroxypoly (oxyethylene)s H-(OCH₂CH₂)_n-OH [1] and α, ω-alkanediols HO-(CH₂)_m-OH [2] were investigated in the presence of zinc acetate at 190°C.1, 2-Bis(p-methoxycarbonyl phenoxy)ethane was also used instead of DMT. The reaction was followed by measuring the amount of methanol distilled from the reaction vessel. Effect of chain lengths of glycol on the reactivity of the transesterification was discussed, and in connection with this, the additional effects of water content and solubility of catalyst in the reactants on this were studied. α-Hydro-ω-hydroxypoly(oxyethylene) (n=2 or 3) exhibited higher reactivity than ethylene glycol (n=1), while the reactivity of glycols (n>5) decreased.
Upon heating glycols [1] or [2] with zinc acetate at 190°C, the insoluble precipitates were formed and in the presence of DMT, the homogeneous solution without any precipitates was formed. These precipitates were considered to be a cyclic coordination zinc compounds, formed by hydroxyl end groups, situated at both sides of glycol chain, with zinc acetate in the case of n=1 of [1], As for glycols (n>2), they might be formed by hydroxyl end groups with -O- bonds. The formation of a chelating cyclic coordination zinc compound reduced the catalytic activity, while any marked tendency to form a chelate compound in the case of α, ω-alkanediols was not observed because of the absence of ether linkages.
The transesterification would reasonably proceed between ester group of DMT and hydroxyl group of glycol which coordinated on zinc atom as ligands.

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The reaction of fibrous cotton cellulose with hexamethylene diisocyanate (HMDI) was studied to obtain the addition product of high nitrogen content. The reaction was carried out by heating cotton linters with HMDI in N, N-Dimethylformamide (DMF). The addition product of the highest nitrogen content (3.02%) was obtained by heating pre-swollen cotton linter (1.00g) with HMDI (9.36g, viz., 6 times of the theoretical amount required for complete reaction between the hydroxyl and the isocyanate groups) in DMF (50 ml) at 153°C for T hr under nitrogen atmosphere. The crystallinity, the solubility in an ethylenediaminecopper (II) complex solution, and the infrared spectrum of the products were studied. The results showed that the crosslinking reaction of cotton cellulose with HMDI started in the amorphous region and proceeded further to the crystalline region at a later stage.

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The ¹³C-NMR lanthanoid-induced shifts of antipyrine by tris-(1, 1, 1, 2, 2, 3, 3-heptafluoro7, 7-dimethyl-4, 6-octanedionato) praseodymium were analyzed using a modified ApSimonBeierbeck method. Contributions of the contact and complex-formation terms were found to be significant as well as the pseudo-contact term, when it was assumed that the contact term was proportional to the carbon 2_S orbital spin density of the antipyrine cation radical in the INDO MO calculation and that the complex-formation term contributed only to the 5-position carbon of antipyrine.

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Removal rate of C₁∼C₄ alkoxyl groups on alkoxylated silica gel surface by heating was investigated, and their pyrolysis products in vacuum were identified.
The change in amount of the alkyl groups with heating time was followed by IR spectroscopy. The removal rate in air increased with increasing carbon numer for straight chain alkyls, and for branched chain alkyls they followed the order: primary>secondary>tertiary; while that in vacuum decreased in this order and was independent of the carbon number of straight chains.
The main constituent of the pyrolysis products was alkene except for methyl group. In air, the removal reaction was considered to be the oxidation of alkyl groups; while in vacuum, it was considered mainly to be the following decomposition:

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In the presence of micelles of HTAB and TBAB in aqueous basic media, new trans-α, β-unsaturated sulfones [2]∼[6] were prepared in good yield (Table 1) from methyl phenyl sulfone and aldehydes. Whereas dichloromethane, toluene or dioxane proved to be a good solvent for the reaction, the condensation reaction did not take place in alcoholic solvents. The reaction of bis(trimethylsilyl)methyl phenyl sulfone with aldehyde was also discussed.

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Decomposition of O-ethyl N-lithio-N-substituted thiocarbamates was accelerated by the addition of excess carbon disulfide or sulfur dioxide, and isothiocyanates were obtained in moderate yields even at room temperature.
O-Ethyl N-lithio-N-phenyl carbamate reacted with carbon disulfide to give phenyl isothiocyanate, but it reacted with sulfur dioxide to afford phenyl isocyanate as the trimer.

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Friedel-Crafts reaction of benzene with 1, 2-dihalogenated propanes, allyl alcohol, 2-phenyl-1-propanol, 1-phenyl-2-propanol, and the related compounds gave a mixture composed of 1, 1- and 1, 2-diphenylpropanes, propylbenzene, and 1, 1-diphenylpropene. The latter two are hydrogenation-dehydrogenation reaction products which are concluded to be formed by intermolecular hydride transfer from 1, 1-diphenylpropane to the intermediate, 1-methyl-2-phenylethyl or 1-phenylpropyl cation. In the case of allylbenzene, the hydride transfer reaction was not observed except at a high reaction temperature. A mechanism which can explain all of the results reported so far is proposed.

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