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Tetsuji Kametani Kazuo Kigasawa Mineharu Hiiragi Haruhide Ishimaru Seiji Haga Keiko Shirayama 《Journal of heterocyclic chemistry》1978,15(3):369-375
2-[4-(1-Oxo-2-isoindolinyl)phenyl]propanoic acid ( 1 ) having a potent analgesic and anti-inflammatory activity could be obtained by three methods, which were found to provide extremely useful ways for the synthesis of 1 from the industrial point of view. (E)- and (Z)-Isomers of 2-butenoic acid and oxiranecarboxylic acid derivatives as the intermedaites in the synthesis of 1 were separated and characterized. Furthermore, the optical resolution of (±)-2-[4-(1-oxo-2-isoindolinyl)phenyl]propanoic acid was successfully achieved using cinchonidine as a resolution reagent. 相似文献
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Yasushi OgawaMasahito Toyama Michinori KarikomiKazuo Haga Tadao Uyehara 《Tetrahedron letters》2003,44(10):2167-2170
Both enantiomers of (P)-(+)-2- and (M)-(−)-2-acetoxy-11,14-dimethyl[5]helicenes 8 were synthesized by asymmetric aromatic oxy-Cope rearrangement of the corresponding chiral bridged bicyclic compounds, which were obtained by enzymatic resolution. The absolute configurations of 8 were assigned by their circular dichroism spectra. 相似文献
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Tadao Ishii Takeshi Tsuchida Ryusaburo Furuichi Hiroshi Haga Kazuhiko Kudo 《Thermochimica Acta》1982,53(1):89-103
The chlorination processes of fly ash and bauxite in the presence of carbon were studied by means of a gas-flow type DTA, X-ray analysis and SEM observation, and the reactivity of Al-compounds as their constituents was compared. In the case of fly ash, the exothermic peak due to the formation of AlCl3 (mainly) and FeCl3 appeared at about 790–920°C. The reactivity of Al estimated from the DTA peak temperature depended on the particle size, carbon content and preparation temperature of fly ash, and was much lower than that of bauxite. Fractional conversion of Al was about 60–70%, when fly ash (?300 mesh) was heated up to 900°C in Cl2 at 5°C min?1 of heating rate. In the case of bauxite, two exothermic peaks due to the chlorination of Fe and Al appeared at about 270 and 490°C, respectively. The chlorination of Al was completed at 550°C under the above conditions. 相似文献
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Naoki Haga Hiroaki Takayanagi Haruo Ogura Yasunao Kuriyama Katsumi Tokumaru 《Photochemistry and photobiology》1995,61(6):557-562
The mechanism of photocycloaddition of 2′-deoxyuridine (1a) and thymidine (1b) to 2,3-dimethyl-2-butene (Bu) in acetonitrile by UV irradiation has been studied. The reciprocal quantum yield for the cycloaddition increased linearly with reciprocal concentrations of Bu in acetonitrile to give limiting quantum yields at infinite concentration of Bu as 0.030 and 0.0096 for 1a and 1b , respectively. This shows that the cycloaddition proceeds in a two-step mechanism between the triplet state of 1 and Bu through biradical intermediates. Addition of cis-1,3-pentadiene quenched the reaction obeying the Stern–Volmer equation. The above quenching experiments and laser transient spectroscopy revealed that the triplet state of 1a reacts with Bu with much larger rate constant (1.3–1.6 × 109 M?1 s?1) than that of 1b (4–5 × 107 M?1 s?1) reflecting larger steric hindrance exerted in the reaction of 1b than that of 1a . 相似文献
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The first syntheses of mono- and dianions of stannole were accomplished by transmetallation or reduction of the novel bi(1,1-stannole). 相似文献