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Direct scandium- and lanthanum-catalyzed etherifications of propargyl alcohols 1 and 6 in MeNO₂-H₂O provided propargyl ethers 3, 4 and 7 in high yields. In addition, reactions of 1 and 6 with thiols exclusively yielded the corresponding propargyl sulfides.

Chiral di- or triamines, ( S )-2-( N , N -disubstituted aminomethyl)indoline 1a – d , derived from ( S )-indoline-2-carboxylic acid were efficient chiral catalysts for the enantioselective addition of dialkylzincs to aldehydes. The best results were obtained by employing 15 mol% of ( S )-2-(4-methylpiperazin-1-ylmethyl)indoline 1c , and chiral secondary alcohols were obtained in up to 97% ee.

Direct scandium- and lanthanum-catalyzed etherifications of propargyl alcohols 1 and 6 in MeNO₂-H₂O provided propargyl ethers 3, 4 and 7 in high yields. In addition, reactions of 1 and 6 with thiols exclusively yielded the corresponding propargyl sulfides.

A variety of 1-sulfanyl and 1-selanyl derivatives are reacted with sodium alkoxides or thiolates to afford the corresponding trisubstituted furan derivatives with high yields [cf.

Chiral di- or triamines, ( S )-2-( N , N -disubstituted aminomethyl)indoline 1a – d , derived from ( S )-indoline-2-carboxylic acid were efficient chiral catalysts for the enantioselective addition of dialkylzincs to aldehydes. The best results were obtained by employing 15 mol% of ( S )-2-(4-methylpiperazin-1-ylmethyl)indoline 1c , and chiral secondary alcohols were obtained in up to 97% ee.

For the application of nanocomposite materials to solid insulator in electric power apparatus, we investigated the influence of the dispersibility of nanoparticles on dielectric property. Experiments were carried out in epoxy/alumina nanocomposites with the particle dispersion techniques using ultrasonic wave and centrifugal force. As the result, we verified the specific characteristics of dielectric permittivity in nanocomposites with good dispersibility.

The catalytic asymmetric borane reduction of prochiral ketones was examined in the presence of chiral diazaborolidine catalysts prepared in situ from chiral β-diamines and borane. Chiral secondary alcohols were obtained with modest to high enantiomeric excesses (up to 92% ee) using ( S )-2-[(4-trifluoromethyl)anilinomethyl]indoline 2f .

The catalytic asymmetric borane reduction of prochiral ketones was examined in the presence of chiral β-diamines. Chiral secondary alcohols were obtained with modest to high enantiomeric excesses (up to 92% ee) using (S)-2-[(p-trifluoromethyl)anilinomethyl]indoline.

The catalytic asymmetric borane reduction of prochiral ketones was examined in the presence of chiral β-diamines. Chiral secondary alcohols were obtained with modest to high enantiomeric excesses (up to 92% ee) using (S)-2-[(p-trifluoromethyl)anilinomethyl]indoline.

Di-, tri-, and tetrahydroxytropolones were prepared in good yields by the acetolysis of corresponding halotropones or polyhalotropolones with acetyl trifluoroacetate followed by acetic acid hydrolysis. However, using the same treatment to obtain hexaacetoxytropone with fully substituted acetoxyhalotropones predominantly yielded fewer substituted acetoxytropones than expected; the mechanism of formation was shown to involve an acetic acid-mediated reduction of intermediary formed acetoxy-p-tropoquinone equivalents. A couple of 2,7-unsubstituted 3,4-diacetoxytropones were deduced to have cyclized 1,3-dioxole structures, 2-acetoxy-2-methyl-5H-cyclohepta-1,3-dioxol-5-ones. An acetolysis of the brominated 5-isopropyltropolones furnished an acetylated by-product, 2,3,7-triacetoxy-5-(1,1-dimethyl-2-oxopropyl)tropone, which might be formed by the acylation of an intermediate, 3,4,5,6-tetraacetoxy-8,8-dimethylheptafulvene.

4-Substituted cis-3-ethyl-2-oxo-1,2,3,4-tetrahydro-2-quinoline was formed as a major product, by irradiation of quinoline N-oxide and 2(1H)-quinolinone substituted with an electron-withdrawing group at the C-4 position in propionic acid. Also, the products were confirmed by direct comparison with synthesized compounds.

Reductive dehalogenated compounds of 2, 3-dichloro-l, 4-naphthoquinone (Dichlone), such as 2-chloro-l, 4-naphthoquinone, 1, 4-naphthoquinone and 1, 4-naphthalenediol, were produced during the initial stage of photochemically reacting Dichlone in various solvents either in the presence or absence of oxygen. On longer photoreaction in the presence of oxygen, phthalic acid and phthalic anhydride (phthalic acid mono ester instead of the anhydride in an alcoholic solvent) were isolated as the main products. Minor products of reacting Dichlone in a mixture of benzene and 2-propanol were salicylic acid, 2-chloro-3-hydroxy-1, 4-naphthoquinone, 2-chloro-3-phenoxy-1, 4-naphthoquinone and 2, 3-dichloro-4-hydroxy-l-keto-2-phenyl-1, 2-dihydronaphthalene, and isopropyl 1-chloro-2, 3-dioxo-l-indanecarboxylate.

The relationship of the β-myrcene content with the susceptibility and/or resistance of Pinus species against the pine wood nematode was investigated. For this purpose, the β-myrcene content of the wood of one-year-old shoots was determined. The resistant trees were found to contain a very small amount of β-myrcene. On the other hand, the β-myrcene content of susceptible trees was comparatively high. This relationship was observed in both inter- and intraspecies and also between young and older trees of the same species, i.e., Pinus densiflora or P. thunbergii. The β-myrcene content can feasibly be used as an indicator for screening resistant Japanese red and black pine trees.

The stimulating effects of monoterpenes in pine trees on the molting and the multiplication of the pine wood nematode were investigated. The results indicated that the molting of the dispersal 4th stage larva (LIV) to the adult nematode was stimulated by these monoterpenes, especially β- myrcene. The population of the nematode cultured on fungal mats of B. cinerea, A. kikuchiana and C. miyabeanus increased considerably in the presence of a small amount of p-myrcene. This compound seemed to play a hormone-like role for both the molting of LIV and the multiplication of the nematode.

“The acetotropy” of 2-acetoxytropones was shown to be a concerted [1,9] sigmatropic process on the basis of a kinetic analysis. A little substituent effect for the activation free energy of the acetyl migration was recognized. Preferred tautomers of polyacetoxytropones were those having the carbonyl group at inner positions. As an extreme case, a “Merry-Go-Round”-type rearrangement was operative in hexaacetoxytropone.

A new convenient assay method for nematode attractants was developed. Using this method, the attracting activity of volatile components in a pine, Pinus densiflora, was examined for the pine wood nematode, Bur saphelenchus xylophilus, which causes serious damage to pine trees in Japan. Among the volatile components, β-myrcene showed the strongest attracting potency. This compound was assumed to play an important role in the transmigration of the nematode from the sawyer to the pine tree and for the movement of the nematode inside the pine wood.

Hormone-like substances corresponding to β-myrcene from pine trees were found from Botrytis cinerea, on which the pine wood nematode multiplied very rapidly. The hormone-like substances of B. cinerea were identified as 3-octanol and l-octen-3-ol. The racemates and optically active compounds of these alcohols exhibited attracting, molting and multiplication activities similar to β-myrcene. These compounds may play an important role in the growth of the pine wood nematode.

(−)-Epicatechin was administered orally to rabbits and vanillic acid, 3-hydroxybenzoic acid, protocatechuic acid, and three kinds of neutral substances were found to be excreted in the urine. The three kinds of neutral substances were identified as 1-δ-(3-methoxy-4-hydroxyphenyl)-, 1-δ-(3-hydroxyphenyl)-, and 1-δ-(3,4-dihydroxyphenyl)-γ-valerolactones, which are optical isomers of the three kinds of neutral substances excreted after administration of (+)-catechin. From the presence of these intermediate metabolites, it was verified that (−)-epicatechin is metabolized by the same mechanism as (+)-catechin described earlier.

Examinations were made on two intermediate metabolites excreted after administration of (+)-catechin to the rabbit. From the infrared and ultraviolet spectra of these two substances (C11H12O3 and C11H12O4) and chemical properties of their various derivatives, they were identified as 3-hydroxyphenyl lactone and 3, 4-dihydroxyphenyl lactone. However, it still remains unknown whether they are δ- or γ-lactone.

2-あるいは4-キノリンカルボニトリルおよび1-あるいは3-イソキノリンカルボニトリルとは異なり, 3-キノリンカルボニトリルおよび4-イソキノリンカルボニトリルは, Grignard試薬などの求核試薬との反応でシアン基の炭素よりもむしろ縮合複素環上の炭素に対して優先的に反応する事実を説明するためにHMOの計算を行ない,また,最適パラメーターも検討した。パラメーターとしてCoulomb積分には縮合複素環中の窒素原子に対しα+0.5β,シアン基の窒素原子に対しα+1.1β, 共鳴積分にはシアン基の炭素-窒素原子間を1.4βにとった場合に反応性指数と化合物の反応実験結果との間によい対応を見いだすことができ,また, IR吸収ならびにプロトンのNMRの化学シフトもよく説明し得ることが判明した。

HMO calculation estimated a tendency of photochemical reaction of quinolinecarbo-nitriles and isoquinolinecarbonitriles in presence of organic acid. The tendency was proved by irradiation on these compounds in the presence of propionic acid and by identification of the reaction products. 2-Ethylquinoline, 2, 4-diethylquinoline, 2-phenylquinoline and 4-ethyl-2-quinolinecarbonitrile were given by the reaction of 2-quinolinecarbonitrile. 3-Quinolinecarbonitrile gave 2-ethyl-3-quinolinecarbonitrile, 4-ethyl-3-quinolinecarbonitrile, 3-cyano-4-ethyl-1, 4-dihydroquinoline and 2, 4-diethyl-3-quinolinecarbonitrile and 4- quinolinecarbonitrile gave 4-ethylquinoline, 2, 4-diethylquinoline and 2-ethyl-4-quinolinecarbonitrile as the reaction products. In isoquinoline series, 1-isoquinolinecarbonitrile gave 1-ethylisoquinoline, 1-phenylisoquinoline, 1, 4-diethylisoquinoline and 4-ethyl-1-isoquinolinecarbonitrile and 4-isoquinolinecarbonitrile gave 1-ethyl- 4-isoquinolinecarbonitrile and 4-cyano-l-ethyl-1, 2-dihydroisoquinoline.

Examinations were made on two intermediate metabolites excreted after administration of (+)-catechin to the rabbit. From the infrared and ultraviolet spectra of these two substances (C11H12O3 and C11H12O4) and chemical properties of their various derivatives, they were identified as 3-hydroxyphenyl lactone and 3, 4-dihydroxyphenyl lactone. However, it still remains unknown whether they are δ- or γ-lactone.

The catalytic asymmetric borane reduction of prochiral ketones was examined in the presence of chiral diazaborolidine catalysts prepared in situ from chiral β-diamines and borane. Chiral secondary alcohols were obtained with modest to high enantiomeric excesses (up to 92% ee) using ( S )-2-[(4-trifluoromethyl)anilinomethyl]indoline 2f .

Mise au point d'un essai biologique du taux d'eclosion de B.x. Il permet de tester ensuite differentes substances inhibitrices de l'eclosion

The reduction of carbon monoxide into methanol has been performed using Everitt's salt {K2FeII[FeII(CN)6]} as a mediator in the presence of homogeneous catalysts at a three-phase (electrode/solution/gas) interface. These conditions enhance the reduction of CO owing to the rapid transport of CO to the active zone of the electrode. The logarithm of the reduction current is linearly related to log (time) with a slope of –1/2 and reaches a constant value after an extensive period of polarization. A theoretical equation for the current against time curve is derived based on a surface-diffusion model in which CO from the gas phase is first adsorbed on the electrode surface and then diffuses along the surface toward the intersection of the three phases; the computed plot of current against time fits the experimental one well.