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Teruyuki Kondo Masato Nomura Yasuyuki Ura Kenji Wada Take-aki Mitsudo 《Tetrahedron letters》2006,47(39):7107-7111
A neutral rhodium(I) complex, ‘RhCl(PPh3)2’ generated by the combination of [RhCl(C2H4)2]2 with a fourfold amount of PPh3, effectively catalyzed the cyclocotrimerization of alkynes (1) and isocyanates (2) to give 2-pyridones (3) and/or pyrimidine-2,4-diones (4), selectively, by controlling the molar ratio of alkynes (1) and isocyanates (2). 相似文献
23.
Y.?FujiiEmail authorView authors OrcID profile Y.?Ishikawa K.?Ohya S.?Miura Y.?Koizumi A.?Fukuda T.?Omija S.?Mitsudo T.?Mizusaki A.?Matsubara H.?Yamamori T.?Komori K.?Morimoto H.?Kikuchi 《Applied magnetic resonance》2018,49(8):783-801
We report the development of a millimeter-wave electron-spin-resonance (ESR) measurement system at the University of Fukui using a 3He/4He dilution refrigerator to reach temperatures below 1 K. The system operates in the frequency range of 125–130 GHz, with a homodyne detection. A nuclear-magnetic-resonance (NMR) measurement system was also developed in this system as the extension for millimeter-wave ESR/NMR double magnetic-resonance (DoMR) experiments. Several types of Fabry–Pérot-type resonators (FPR) have been developed: A piezo actuator attached to an FPR enables an electric tuning of cavity frequency. A flat mirror of an FPR has been fabricated using a gold thin film aiming for DoMR. ESR signal was measured down to 0.09 K. Results of ESR measurements of an organic radical crystal and phosphorous-doped silicon are presented. The NMR signal from 1H contained in the resonator is also detected successfully as a test for DoMR. 相似文献
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α,β-Unsaturated ketones were obtained from alkylphenylketene and aroyl chloride via decarbonylation reaction in the presence of catalytic amounts of tetrakis(triphenylphosphine) palladium. 相似文献
25.
Phthalaldehyde reacted with primary amines in the presence of tetracarbonylhydridoferrate under mild conditions to give 2-substituted isoindoles and/or isoindolines in good to excellent yields. Aliphatic amines gave selectively the isoindolines but aromatic amines had a great tendency to the isoindoles. 2-(2-Tolyl)-, 2-(4-tolyl)-, 2-(4-methoxyphenyl)-, 2-(3-chlorophenyl)-, 2-(4-chlorophenyl)- and 2-(3,4-dichlorophenyl)-isoindole were prepared by this method. 相似文献
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Recent progress of the preparation of novel materials for catalysts utilizing metal-containing silsesquioxanes are reviewed
in the following categories: (i) activities of vanadium or titanium-containing silsesquioxanes as homogeneous catalysts for
oxidative reactions, (ii) preparation of immobilized or polymeric catalysts, and (iii) preparation of porous oxide catalysts
utilizing metal-containing silsesquioxanes. The present authors found that the liquid phase photo-oxidation of cyclohexane
in the presence of a vanadium-containing silsesquioxane as a homogeneous catalyst selectively afforded cyclohexanol and cyclohexanone
in high yields. Facile synthetic methods for group 4 metal-containing silsesquioxanes with functionalized silyl (or germyl)
groups are presented. Remarkably, titanocene(IV)-containing silsesquioxanes have been synthesized for the first time. The
presence of alkenylsilyl substituents shows a promotional effect on the epoxidation of cycloalkenes, which was found to be
more significant for titanium-bridged silsesquioxanes. By utilizing these silsesquioxanes, polymeric, starburst-like, and
dendritic silsesquioxanes were prepared as well as novel caged or macrocyclic molecules with organic–inorganic hybrid structures.
The controlled calcination of these metal-containing silsesquioxanes at around 823 K produces porous oxides with high BET
surface areas of 300–520 m2g−1 and uniformly-controlled micropores of 0.5–0.6 nm diameter. The oxides are found to include a well-dispersed metallic oxide
species. From group 13 elements-containing silsesquioxanes Br?nsted acidic oxides are produced. Among them, aluminum-containing
oxides show excellent activities for the cracking of cumene even at low temperature, 523 K, in spite of their amorphous nature. 相似文献
29.
Shi-Wei Zhang Take-aki Mitsudo Teruyuki Kondo Yoshihisa Watanabe 《Journal of organometallic chemistry》1993,450(1-2):197-207
Allylic carbonates except for allyl methyl carbonate reacted with carbonucleophiles such as ethyl acetoacetate in the presence of a catalytic amount of Ru(cod)(cot) [cod = cycloocta-1,5-diene, COT = cycloocta-1,3,5-triene] in N-methylpiperidine at 80°C to give the corresponding monoallylated carbonucleophiles in high yields with high regioselectivity. The regioselectivity was quite different from that in the palladium-catalyzed reactions. The allylation of carbonucleophiles using allyl methyl carbonate selectively gave the diallylated carbonucleophiles in high yields. 相似文献
30.
[RuCl2(CO)3]2/Et3N and (eta 3-C3H5)RuBr(CO)3/Et3N are highly effective catalyst systems for carbonylative cyclization of allylic carbonates with alkenes to give the corresponding cyclopentenones in high yields. For example, treatment of allyl methyl carbonate (1a) with 2-norbornene (2a) in the presence of a catalytic amount of [RuCl2(CO)3]2 (2.5 mol %) and Et3N (10 mol %) at 120 degrees C for 5 h under 3 atm of carbon monoxide gave the corresponding cyclopentenone, exo-4-methyltricyclo[5.2.1.0(2,6)]dec-4-en-3-one (3a), in 80% yield with high stereoselectivity (exo 100%). 相似文献