Second generation metallosalen complexes bearing binaphthyl units as their chiral auxiliaries serve as efficient catalysts for a variety of asymmetric reactions. To date, however, only the complexes of the first transition series of metals have been used as asymmetric catalysts and asymmetric catalysis of the complexes of the second transition series of metals still remains unexplored. Recently, we synthesized second generation(R, S)- and(R, R)-(chloro)(nitrosyl)(salen)ruthenium complexes and examined their asymmetric catalysis, which was found to be considerably different from that by the salen complexes of the first transition metals. The most salient feature of these new(salen)ruthenium complexes is that they are activated upon photo-irradiation and are inert in the dark. Furthermore, they show novel catalysis that can not be achieved by(salen)metal complexes of the first transition series of metals. For example, (R, S)-(nitrosyl)(salen)ruthenium complex could be successfully used as the catalyst for asymmetric and stereospecific epoxidation of cis- and trans-olefins, and high cis- and enantioselective cyclopropanation was for the first time achieved by using(R, R)-(nitrosyl)(salen)ruthenium complex as the catalyst. Furthermore, aerobic asymmetric oxidation of secondary alcohols was also achieved with the same complex as the catalyst.

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The homogeneous isomerization and hydrogenation of allylbenzenes(allylbenzene, eugenol, 2-allylphenol and esdragole) catalyzed by [RhH₂(Ph₂N₃)(PPh₃)₂](dihydridorhodium complex) in dimethyl sulfoxide(DMSO) under a hydrogen atmosphere(1atm) at 303K was studied. The highest catalytic activity was observed with allylbenzene as a substrate. The reaction products of isomerization and hydrogenation of allylbenzene were trans- and cis-1-propenylbenzene and propylbenzene. The isomerization rate under hydrogen atmosphere was faster than that under nitrogen atmosphere, suggesting that more active species were formed through the reaction of dihydridorhodium complex and hydrogen. A trace amount of the hydrogenated product was detected by use of other solvents(N, N-dimethylformamide, tetrahydrofuran, acetone, benzene and toluene). The mechanisms of isomerization and hydrogenation were proposed on the basis of present results together with our previous reports.

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β-Cyclodextrin derivatives as ligands(β-CD-6-PA and β-CD-2-PA) were prepared by the monoesterification of the hydroxy group at the C-6 or C-2 position of β-CD with 3, 4-dihydroxybenzoic acid(protocatechuic acid, PAH) with KF in DMF. Direct hydroxylation of benzene with hydrogen peroxide was performed by the iron(III) coordinated the β-CD ligands(the improved Hamilton system). The β-CD-6-PA and iron(III) formed a highly active catalyst for the hydroxylation, composed of 1:2 complex(Fe:ligand)at pH of 2.5, but an inert one(1:3 complex) at pH of 6.0. The stability of the iron(III)-β-CD complex(1:3 (λ_max536nm, ε=2030, logK′=13.8)) was higher than that of 1:2 complex(λ_max667nm, ε=860, logK′=8.66). At the optimum pH of 2.5, when the β-CD-6-PA-Fe(III) catalyst was used for the hydroxylation, yields of catechol, hydroquinone, and phenol were 73, 5 and 22%, respectively. On the other hand, when the β-CD-2-PA-Fe(III) catalyst was used, these yields were 10, 24 and 12%, respectively. The observed selectivity of products in the present hydroxylation is discusssed in terms of a position of PA substituent of β-CD-PA-Fe(III) catalyst.

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The Electron Spin Resonance(ESR) spin-trapping technique using 5, 5-dimethyl-1-pyrroline N-oxide(DMPO) as a spin trap was used to detect oxygen radicals as an active species in the hydroxylation of benzene with hydrogen peroxide catalyzed by the protocatechuate-Fe(III)complex. The electronic property of the substituted group of the catechol derivatives affected the signal intensities of DMPO-OH radical(hydroxyl radical trapped) in the pH range of 1-6, and it showed two dependent patterns on pH. The lowest signal intensity of DMPO-OH was shown at pH of 2.5 where the hydroxylation was most active in the presence of the Fe complex of β-cyclodextrin-protocatechuate(β-CD-6-PA). The signal strength, however, reached its maximum at the pH of 1 where the reaction was almost inactive. These changes in signal intensities of DMPO-OH in the pH range of 1-6 revealed that the OH radical is not a main active species in this hydroxylation system. The active species of the hydroxylation through the non-hydroxyl radical process would be directly formed in the ternary complex from hydrogen peroxide, β-CD-6-PA and iron ion at pH of 2.5. It will be similar to a resonance hybrid of an o-quinone-iron oxide radical proposed for the mechanism of the Hamilton reaction.

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Dextran was carboxymethylated and sulfated to prepare sulfated CM-dextrans with various degree of substitution in order to investigate the interaction between acidic polysaccharides and fibroblast growth factors(FGFs). It was shown that CM-dextran with low degree of sulfation slightly activated FGFs. It was concluded that the degree of anionization was more effective than the kinds of sugars or linkages on the activation of FGFs.

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In this paper, we report properties and weatherability of the poly(ester/amide) containing norbornadiene moieties in the main chain(P-1).
The thermal properties of P-1 were investigated by TGA and DSC analyses.The T_g of P-1 stood at 119°C, and a 5% weight loss was recorded at 348°C. The photoirradiated P-1 film containing quadricyclane(QC) groups released about 228J/g of thermal energy. Weatherability of P-1 was evaluated during on the outdoor exposure test in Yokohama for 3 months. The stored thermal energy of the QC groups in P-1 gradually decreased as the outdoor exposure proceeded. These results are attributed to the cross-linking formation and the main chain rupture of P-1 during the outdoor exposure.
The top-coating with PVA film and cover with glass plate on P-1 was proved to be very effective to improve the weatherability of P-1 film. It was also found that light stabilizers enhanced the weatherability of P-1 film.

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In order to realize ideal UV absorbers which do not disturb UV curing processes and yet can act as a absorber, the hydroxy group of 2-(2H-benzotriazol-2-yl)phenol was blocked with a diphenylphosphinyl group and the properties of the resulting blocked benzotriazole derivative were examined.
The results indicated that the triazole showed almost no negative effect on the UV curing processes, but improved the weatherbility of the cured paints.
Spectroscopic studies were carried out in order to reveal the origin of the present observations, which suggested that strong emission from the benzotriazole played an important role.

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Recycle of ceria-based glass polishing powder was investigated. A waste polishing powder was treated in a 4molkg^-1 NaOH solution with a waste/NaOH weight ratio of 1 at 60°C, and SiO₂ and Al₂O₃ impurities were dissolved into the solution and removed from the polishing powder. A solution which containing the impurities was heated to 100°C, and hydroxysodalite(Na₈(AlSiO₄)₆(OH)₂4H₂O) was precipitate. Thus the glass polishing powder can be regenerated and hydroxysodalite was obtained as a by-product, and excess NaOH solution was reused. However addition of Si source, such as sodium silicate was required to control the leaching and precipitation process.

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Synthesis of high-silica zeolites in the presence of 1-butanol(n-BuOH) was conducted under various conditions to explore the role of silica source, aging time, and n-BuOH.
It was found that the solubility of the silica source in the aqueous phase was a critical factor for the formation of zeolite precursor when KOH was employed as an alkali source. MFI(ZSM-5) type zeolites were obtained when fumed silica with small BET specific surface area was employed, whereas TON(Theta-1) type zeolites were formed when fumed silica with large BET specific surface area was employed. It was also found that the addition of n-BuOH suppressed the formation of cristobalite. This is probably due to the reduction of the Si concentration in the aqueous phase of the synthesis gel. FT-IR and ¹³C CP MAS NMR measurements of as-made zeolites suggested that n-BuOH molecules were occluded in the zeolitic pores of TON and MFI type zeolites at the initial stage of crystallization.

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Under nitrogen atmosphere an unsaturated carbon-carbon double bond was hydrogenated to give a saturated one with nickel catalyst system(NiBr₂/Zn/H₂O/EtOH). It was found that hydrogen gas was generated from water and zinc powder by using metallic nickel catalyst, which was prepared from anhydrous nickel bromide and zinc powder. Metallic nickel was an active species for the reaction and zinc powder was a reagent to produce hydrogen. A probable pathway was presented.

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