Oxidative addition of Ru(η⁵-C₅R₅)L, ₂X(R=H or CH₃;L=C0 or Ph₃P; X=Cl or Br) or [Ru(η⁵-C₅Me₅)Cl₂]₂ with allylic halides gives new series of allylruthenium(IV) complexes, Ru-(η⁵-C₅R₅)(η³-CH₂CHR'CH₂)X₂. The structure of the representative one (R=CH₃ ; X=Br) was determined unequivocally by single crystal X-ray analysis and ¹H-and ¹³C-NMR spectros-copy. These allylruthenium (IV) complexes and the known Ru (1-3 : 6-7 : 10-12-η-C₁₂-H₁₈)Cl₂ were successfully methylated by means of CH₃MgX or equimolar quantity of CH₃Li to yield thermally stable allylhalomethylruthenium(IV) complexes. These alkyl complexes induces selective reductive elimination accompanying the carbon-carbon bond formation between methyl and allyl ligands in the presence of CO, t-BuNC, etc., at elevated temperatures. Alkylation with an excess CH₃Li or Me₃Al furnished purely organometallic dimethyl com-plexes, Ru(η⁵-C₅R₅)(η³-C₃H₅)(CH₃)₂, which were converted to Ru(C₅R₅)(η³-CH₂CHCHCH₃)L (L=CO or t-BuNC) upon heating with evolution of methane. Alternatively, extremely facile β-hydride elimination followed by the C-H bond-forming reductive elimination took place even below -20°C, when Et₃Al or BrMg (CH₂)₄MgBr were employed as alkylating reagents. The reactivity of the Ru(IV)-C bonds are, therefore, in the following order, β-elimination> reductive elimination to form C-H bonds>>reductive elimination to form C-C bonds. It is noteworthy that the insertion of CO, t-BuNC, or alkenes into the Ru(IV)-C bonds was never observed at all. On the other hand, cationic ruthenium active species, [Ru(C₅R₅)(η⁴-butadiene)]⁺ induces oxidative cyclization with the second molecule of butadiene to give stoichiometric and catalytic linear di- and trimerization (R=H) or cyclodimerization (R=CH₃) of butadiene.

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Oxidative dehydroaromatization of propylene was investigated by the pulse technique over two kinds of single oxide catalysts. With the Bi₂O₃ catalyst, the main dimer product was 1, 5-hexadiene, and the dimerization activity was stable to pulse number even if the catal was partly reduced to the bulk. With the CeO₂ catalyst, benzene was mainly formed insteyasdt of 1-5-hexadiene, but the activity decreased rapidly with increasing pulse number, indicating that only the lattice oxygen near the catalyst surface could be used for oxidative dimeriza tion and the further aromatization. The Bi-Ce-O system catalyst was found in this study to give higher aromatization activit and showed better stability, compared to the Bi-Sn-O catalyst. Although the Bi-Ce-Oy catalyst was only a mixture of the two component oxides from X-ray diffraction analysis, th ere was a significant combination effect on the selectivity to benzene. The highest and the most stable selectivity of benzene was obtained at Bi/Ce=1. In the TPD spectrum of Bi-Ce-O catalyst, there are not only the lattice oxygen (β-oxygen) over 620°C due to the reduction of Bi₂O₃, but also a great deal of the a-oxygen desorbed about 400°C, which is considered the absorbed oxygen in the bulk. This absorbed oxygen could probably be a compensation of the lattice oxygen through the route of gaseous→absorbed→lattice oxygen in the binary catalyst system. By the kinetic study on the Bi-Ce-O catalyst, the dimer formation rate was the first-order with respect to the partial pressure of propylene and zero-order of oxygen. Although detail investigation would be made further, it was considered that the complete oxidation of propylene would mainly take place parallelly on some different sites, and the rate-determining step of propylene dimerization occurred probably between an adosrbed propylene and a gaseous one by an Eley-Rideal type mechanism.

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In the application of ICP atomic emission spectrometry using the direct graphite cup insertion technique to solution samples, complicated emission time profiles are often obtained. It is important to elucidate mechanisms resulting in such profiles for wide application of this technique. In this study, the insertion speed of the cup into the plasma and the rate of the temperature rise of the cup were estimated for the help of understanding the mechanisms. Then signal characteristics of nitrate, chloride and sulfate of metals were investigated and the mechanisms were discussed. Both hydrochloric and nitric acids gave double peaks in the 198 19 * 14: 1991 No.3time profiles of the first six elements among Mg, Al, Ga, Ge, As, Sb, Pb, Ge, Fe, Mg, Al, Cr, Cu, Ga, Sb and Cd. Sulfuric acid gave single-peak profiles for all the elements examined except Ga and Ge. The double peak is due to two vaporization processes of oxides; the sublimation of the oxides followed by atomization in the plasma and thermal decomposition or reduction by carbon of the oxides. The profile of Al in the chloride form differed from that in the nitrate. The large dissociation energy and vapor pressure of AlCl₃ are responsible for the result. In conclusion, sulfuric acid is preferable for the direct graphite cup insertion tech nique since it gives single peaks for many elements.

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2, 5-Dimethylacetophenones 1 and 2, 5-dimethylbenzophenones 2 with a variety of substituents (H, CH₃, OCH₃, Cl) have been reacted with fuming nitric acid in acetic anhydride to give the corresponding 2-(nitromethyl)acetophenones 3 and 2-(nitromethyl)benzophenones 4, respectively. The nitration of the compounds 1 and 2 bearing methyl or methoxyl groups at the 4-position has afforded the corresponding 3 and 4 in high yields. The nitration of compounds unsubstituted at the 4-position gave the products of a complex mixture. The compounds 1 and 2 with the highest HOMO electron density at the 5-position (according to MNDO calculations) have been selectively nitrated to lead to the compounds 3 and 4.

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Diazaanthracenonaphthalenophane 2 and diazaanthracenophane 3 with trifluoroacetyl group on their nitrogen atom were newly synthesized. The electronic spectra and reactivities of 2 and 3 were compared with those of diazaanthracenoparacyclophane 1 which was previously reported by ourselves. Compounds 2 (yellow and nonfluorescent) and 3 (red and nonfluorescent)underwent the photocyclization similarly to 1 (greenish yellow and fluorescent). Quanturn yields of the photocyclization of both 2 and 3 were about O.5, twice as much as that of 1 (Table 2). The photoreaction of 1 was quenched by oxygen, while those of 2 and 3 were not quenched (Table 2). The original compound 2 was recovered more slowly by heating the photoproduct of 2 than similar reaction related to 1 (Figs.3 and 4, and Table 2). On the other hand, 3 was not recovered by heating the photoproduct of 3 (Fig.5). Interestingly 3 underwent a novel ( 4π+4π ) thermal dimerization (cyclization) (Fig.8 and Table 2).

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The oxidation of 1, 2, 3, 4-tetrahydroquinoline (THQ) was investigated to provide new utilizations of quinoline, a major component of tar bases in coal tar and coal liquid. The oxidation proceeded smoothly by molecular oxygen in acetic anhydride in the presence of catalytic amounts of transition metal acetates and certain bromides, affording 1-acety1-4-ace-toxy1, 2, 3, 4-tetrahydroquinoline (AATHQ) and 1-acetyl-2, 3-dihydro-4(1H)-quinolinone (ADHQ) as main products. Active catalyst s ystems were Co(II)-NH₄Br, Co(II)-Mn(II)-NH₄Br, and Co(II)-Ce(III)-NH₄Br, optimum Co(II) concentration and Br/Co ratio being 6.0 x 10-² mol/kg and 2.0, res-pectively, in Co(II)-NH₄Br catalyzed reactions. The effects of reaction temperatures, concentrations of THQ, and weight ratios of acetic anhydride to acetic acid on the oxidation yield were also examined. The oxidation of THQ catalyzed by Co(II)-NH₄Br in acetic anhydride at 110°C produced AATHQ in 60% yield.

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A specific and highly sensitive detection method for protein was developed. The method is the combination of protein separation with affinity chromatography and the staining method by colloidal platinum. By using this method human serum albumin and human insulin were detected with high sensitivity such as 1 ng.

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Multifunctional polymeric photosensitizers containing both pendant nitroaryl groups as photosensitizing moieties and pendant carboxylate anion as a substrate-attracting group were synthesized by radical copolymerization of ρ-(4-nitrophenoxymethyl)styrene (NPMS) or ρ-(4-nitro-1-naphthoxymethyl) styrene (NNMS) with methacrylic acid (MA) followed by neutrali-zation of the resulting copolymers with various bases such as NaOH, KOH or LiOH. Since thus obtained polymers were soluble in methanol or water, photo-isomer ization of (2-cinnamoyloxyethyl) trimethylammonium bromide was essentially carried out in water in the presence of the photosensitizers. These results suggested that multifunctional polymeric photosensitizers containing both pendant photosensitizing groups and anionic substrate-attracting group prepared from NPMS-MA have higher photosensitization efficiency than the poly-meric photosensitizer prepared from NNMS-MA. Furthermore, it was found that the photo-sensitization efficiency was strongly affected by content of photosensitizing unit in the copoly-mer, species of the counter cation of pendant carboxylate, and reaction medium.

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Three kinds of a-olefinic liquid crystals, 4-[4-[(S)-2-methylbutoxycarbonyl]phenoxycar-bonyll]phenyl 10-undecenoate 1, 4-[4-[(S)-2-methylbutoxycarbonyl]phenyl]phenyl 10-undece-noate 2, and (S)-2-methylbutyl 4-[N-4-(10-undecenoyloxy)benzylideneamino]cinnamate 3were synthesized as reactive monomers for ferroelectric liquid crystalline comb-like polysiloxanes.1 shows a smectic A(S_A) state, while 2 and 3 show both S_A and chiral smectic C (S_C) state. From the electrooptical measurements, the response times for dual frequency drive in S_A state were found to be 30, 310, and 30 ms at O.1 Hz : 2.12, 7, and 2.67 s at 1 kHz for 1, 2 and 3, respectively. The response time for SSFLC in S_C phase was also found to be 460 and 105 μs for 2 and 3, respectively.

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Changes of relative ratios of fuel aromatics found in pyrolyzing soot as combustion time passes were compared to those in the diffusion flame of aromatics mixture. The soot was collected at both positions, in the flame (1) and above the flame (2), at every 30s after ignition. As a result of pyrolyzation of soot (1) at 358°C, the ratio of benzene decreased. and the ratio of ρ-xylene increased in proportion to the change of these ratios in the flame. In a result of pyrolyzation of soot (2) at 590°C, the ratios of benzene and toluene did not change, but the ratio of ρ-xylene increased in proportion to the ratio of ρ-xylene in the flame.

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N-Benzylation of phenanthro[9, 10-d]triazole gave the mixture of 1-benzyl-1H- and 2-benzyl-2H-phenanthro[9, 10-d]triazole (1c and 2c) such as N-Alkylation. The mass specctrometry can be used to distinguish clearly between the 1-alkyl-1H- and 2-alkyl-2Hphenanthro-[9, 10-d]-triazole. The 1-alkyl compound releases more N₂H, which is further split with the (R-H) elimination to give base peak m/z 190, than do the 2-isomer, and so on the mass spectrun of 2-alkyl compound a base peak is parent peak. However the fragmenta tion patterns of the two benzyl compounds show similarities so structures are proposed for these fragment ions by consideration of rearrangement fragment C₁₄H₈N⁺(m/z 190) and C₆H₅CH₂⁺ (m/z 91).

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Several compounds were isolated from two Japanese wild Salvia species, S. japonica THUNB, and S. glabrescens MAKINO. They were triterpenoids, steroids, a phenolic compound, and a carbohydrate, but a diterpenoid was not found. Their structures were identified as β-sitosterol, β-sitosterol glucoside, ursolic acid, oleanolic acid, 2α-hydroxyursolic acid, maslinic acid, tormentic acid, caffeic acid, and ethyl β-_D-galactopyranoside by the comparison of spectroscopic data with those of the authentic samples.

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Nonbilayer films (Fig.2 a and b) spontaneously formed during solvent cast of additives (type I in Fig.1) and polyion complexes (PIC) prepared from quaternary ammonium type amphiphiles, [CH₃(CH₂)_n-1]2N⁺(CH₃)₂⋅Br^-(2C_nN, n=16, 18, 20) and poly(p-styrenesulfonate)(PSS) or poly[2-(acrylamido)-2-methyl-l-propanesulfonate] (PAMPS). An important factor for the formation of nonbilayer structure was an increase in the molar volume of a hydrophobic part rather than hydrophilic part in the PICs by additives, but not chemical structure of additives.

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