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131.
Imai M Tanaka M Tanaka K Yamamoto Y Imai-Ogata N Shimowatari M Nagumo S Kawahara N Suemune H 《The Journal of organic chemistry》2004,69(4):1144-1150
Intermolecular hydroacylation between salicylaldehydes 1, 26-40 and 1,4-penta- or 1,5-hexadienes 4-13 by Rh-catalyst proceeded under mild reaction conditions to give a mixture of iso- and normal-hydroacylated products 14-25, 41-55, and 57-60. In the hydroacylation reaction, chelation of both salicylaldehyde and diene to the Rh-complex plays a crucial role. The ratio of iso- and normal-hydroacylated products could be regulated by the addition of salicylic acid or amines. The effects of various Rh-complexes, solvents, and additives were examined, and the plausible mechanisms of the catalytic cycle were proposed on the basis of the deuterium-labeling salicylaldehyde experiments. 相似文献
132.
Masaru Yoneyama K. D. Athula Kuruppu Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1988,26(11):2917-2922
Aromatic polyamides (aramids) having inherent viscosities of 0.5–1.10 dL/g were prepared by the direct polycondensation of 1,1,3-trimethyl-3-(4-carboxyphenyl)indane-5-carboxylic acid with various aromatic diamines using triphenyl phosphite and pyridine as the condensing agents. Copolyamides were also prepared by a similar procedure from a mixture of the phenylindane diacid, terephthalic acid, and p-phenylenediamine. Almost all of the aramids were soluble in a variety of solvents such as N-methyl-2-pyrrolidone, pyridine, and m-cresol, and afforded transparent and tough films by the solution casting. These aramids and copolyamides had glass transition temperatures in the range of 290–355°C, and started to lose weight at 340°C in air. 相似文献
133.
Hwa-Jin Jeong Yoshiyuki Oishi Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1990,28(12):3293-3301
A new highly phenylated heterocyclic diamine, 3,4-bis(4-aminophenyl)-2,5-diphenylfuran, was synthesized in three steps from 4–-nitrodeoxybenzoin. The low temperature solution polycondensation of the diamine with various aromatic diacid chlorides afforded tetraphenylfuran-containing aromatic polyamides with inherent viscosities of 0.2–0.8 dL/g. Copolyterephthalamides were obtained from the diamine and 4,4′-oxydianiline. The polyamides were generally soluble in a wide range of solvents that included N,N-dimethylacetamide, N-methyl-2-pyrrolidone, pyridine, and m-cresol. Glass transition temperatures of the polyamides and copolyamides ranged from 302–342°C, and 10% weight loss was observed above 480°C in nitrogen. 相似文献
134.
Fabrication of mesoporous ZnO nanosheets from precursor templates grown in aqueous solutions 总被引:1,自引:0,他引:1
Keita Kakiuchi Eiji Hosono Toshio Kimura Hiroaki Imai Shinobu Fujihara 《Journal of Sol-Gel Science and Technology》2006,39(1):63-72
Mesoporous ZnO nanosheets were successfully prepared by pyrolytic transformation of zinc carbonate hydroxide hydrate, Zn4CO3(OH)6·H2O. The nanosheets were initially formed as assemblies on glass substrates during chemical bath deposition (CBD) in aqueous
solutions of urea and zinc acetate dihydrate, zinc chloride, zinc nitrate hexahydrate, or zinc sulfate heptahydrate at 80°C.
It was key to induce heterogeneous nucleation of Zn4CO3(OH)6·H2O by promoting a gradual hydrolysis reaction of urea and controlling the degree of supersaturation of zinc hydroxide species.
Morphology of Zn4CO3(OH)6·H2O was largely influenced by the anions present in the CBD solutions. The Zn4CO3(OH)6·H2O nanosheets were transformed into wurtzite ZnO by heating at 300°C in air without losing the microstructural feature. 相似文献
135.
New fan-shaped ionic liquids forming columnar liquid crystalline phases have been prepared to obtain one-dimensional ion-transporting materials. The ionic liquids consist of two incompatible parts: an imidazolium-based ionic part as an ion-conducting part and tris(alkyloxy)phenyl parts as insulating parts. Two compounds having octyl and dodecyl chains have been synthesized. Self-assembly of these materials leads to the formation of thermotropic hexagonal columnar liquid crystalline states at room temperature. Anisotropic one-dimensional ionic conductivities have been successfully measured by the cells having comb-shaped gold electrodes. The self-organized columns have been aligned macroscopically in two directions by shearing perpendicular and parallel to the electrodes. The ionic conductivities parallel to the column axis are higher than those perpendicular to the axis. The incorporation of lithium salts in these columnar materials leads to the enhancement of the ionic conductivities and their anisotropy. These materials would be useful for anisotropic transportation of ions at the nanometer level. 相似文献
136.
Wataru Sugimoto Masashi Omoto Katsunori Yokoshima Yasushi Murakami Yoshio Takasu 《Journal of solid state chemistry》2004,177(12):4542-4545
An ion-exchangeable ruthenate with a layered structure, K0.2RuO2.1, was prepared by solid-state reactions. The interlayer cation was exchanged with H+, C2H5NH3+, and ((C4H9)4N+) through proton-exchange, ion-exchange, and guest-exchange reactions. The electrical and magnetic properties of the products were characterized by DC resistivity and susceptibility measurements. Layered K0.2RuO2.1 exhibited metallic conduction between 300 and 13 K. The products exhibited similar magnetic behavior despite the differences in the type of interlayer cation, suggesting that the ruthenate sheet in the protonated form and the intercalation compounds possesses metallic nature. 相似文献
137.
Yoshio Fuchita Katsuma Hiraki Yasuhiro Matsumoto 《Journal of organometallic chemistry》1985,280(2):c51-c54
N,N-Dimethylneopentylamine reacts with Pd(MeCO2)2 to give a novel trinuclear cyclopalladated complex [Me2NCH2CMe2CH2Pd(μ-MeCO2)2Pd(μ-MeCO2)2PdCH2CMe2CH2NMe2]?-0.5C6H6 (I). The reaction of I with PPh3 affords both trans-[Pd(MeCO2)2(PPh3)2] (II) and [Pd(CH2CMe2CH2NMe2)(MeCO2)(PPh3)] (III). The reaction of III with LiCl yields a mononuclear cyclopalladated complex, [Pd(CH2CMe2CH2NMe2)Cl(PPh3)] (IV). 相似文献
138.
Synthesis of benzylidene-pendant polyphthalimidines from flexible bisphthalides and various diamines
Yoshio Imai Takeyoshi Takahashi Renzhi Nan Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》1983,21(5):1241-1249
New polyphthalimidine-forming monomers, 5,5′-(oxydi-p-phenylenedicarbonyl)bis(3-benzylidenephthalide) and the 6,6′-derivative, were synthesized by the Friedel–Crafts reaction of diphenyl ether with 5- and 6-chloroformyl-3-benzylidenephthalide, respectively. The direct polycondensation of these bisphthalides with both aliphatic and aromatic diamines in o-phenylphenol at 200–250°C afforded polyphthalimidines having inherent viscosities of 0.2–1.2 dL/g in almost quantitative yields. Syntheses of aliphatic polyphthalimidines with higher inherent viscosities were also achieved by a two-step procedure involving ring-opening polyaddition and subsequent thermal cyclodehydration. All the polymers were amorphous and readily soluble in N-methyl-2-pyrrolidone (NMP), m-cresol, nitrobenzene, pyridine, and chloroform. Tough and flexible films could be cast from NMP solutions of the polymers. Glass transition temperatures of the polyphthalimidines were in the range of 158–246°C. The thermogravimetry of the aromatic polymers showed 10% weight loss in air and nitrogen at 445–515 and 500–520°C, respectively. The crosslinking reaction of some benzylidenependant polyphthalimidines took place at 300°C through double-bond addition to afford cured polymers with improved thermal stability. 相似文献
139.
Yoshio Imai Takeyoshi Takahashi Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》1981,19(11):2841-2845
Two aminophthalide monomers, 6-amino-3-benzylidenephthalide (I) and 3-(p-aminobenzylidene)phthalide (II), underwent self-polycondensation in o-phenylphenol at 250°C to yield polyphthalimidines with inherent viscosities up to 0.5 dL/g. These polymers were readily soluble in a variety of solvents such as dimethylformamide, dimethyl sulfoxide, m-cresol, pyridine, and methylene chloride. The temperatures at which a 10% weight loss occurred by thermogravimetry in nitrogen were 460°C for the polymer derived from I and 490°C for the polymer from II. The glass transition temperature of the polymer from I was 332°C, determined by thermomechanical analysis. 相似文献
140.
The simultaneous determination of silicate, phosphate and arsenate by using flow-injection analysis with on-line column separation is described. Determinations are based on measurement of the absorbance at 810 nm of the heteropoly blue formed with ascorbic acid as reducing reagent. Effects of flow rates, temperature of reaction coils and sample injection volumes are reported; optimum conditions are 0.25 ml min?1 for the ascorbic acid stream, 95°C for the reaction coils and 300 μl for the injection volume. With the anion-exchange column (TSK-gel SAX), the optimal flow rate of the eluent is 0.75 ml min?1. Relative retention times depend on the concentration of the KCl/NH3/EDTA eluting solution; separation and simultaneous determination of the three ions are satisfactory at around 10?4 mol l?1 concentrations of the three ions. 相似文献