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101.
Hoshi T Nakazawa T Saitoh I Mori A Suzuki T Sakai J Hagiwara H 《Organic letters》2008,10(10):2063-2066
High activity in the palladium-catalyzed Suzuki-Miyaura reactions of aryl chlorides with arylboronic acids was furnished using biphenylene-substituted di- tert-butylruthenocenylphosphine (R-Phos) as a supporting ligand. Substrate combinations even for the construction of highly hindered tetra- ortho-substituted biaryls can be achieved in good to excellent yields with low catalyst loadings in short reaction times. 相似文献
102.
Masakatsu Matsumoto Masatoshi Tanimura Taichi Akimoto Nobuko Watanabe Hisako K. Ijuin 《Tetrahedron letters》2008,49(26):4170-4173
An aprotic polar solvent such as N-methylpyrrolidone (NMP) promoted the thermal decomposition of bicyclic dioxetane bearing a 4-(benzothiazol-2-yl)-3-hydroxyphenyl moiety 1 without the addition of any base. This solvent-promoted decomposition (SPD) gave light as effectively as the base-induced decomposition (BID) in an aprotic polar solvent. SPD caused intramolecular CT-induced chemiluminescence similar to BID, but, in contrast to BID, SPD proceeded through a pathway with a large negative entropy of activation. Dioxetane 1 was also shown to give light due to excited state intramolecular proton transfer (ESIPT) upon heating in p-xylene. 相似文献
103.
Taichi Kano 《Tetrahedron letters》2008,49(37):5369-5371
A binaphthyl-based amino sulfonamide (S)-2 was applied to the direct asymmetric aminoxylation of aldehydes with nitrosobenzene. The reaction catalyzed by (S)-2 proceeded smoothly to give the aminoxylated product in good yield with excellent enantioselectivity. This method represents a rare example of the highly enantioselective aminoxylation by a non-proline type catalyst with high catalytic performance. 相似文献
104.
A direct asymmetric iodination reaction of aldehydes with NIS was found to be catalyzed by the novel axially chiral bifunctional amino alcohol (S)-1d. This method represents the rare example of the catalytic and highly enantioselective synthesis of optically active alpha-iodoaldehydes. 相似文献
105.
Kusakabe T Kato K Motodate S Takaishi S Akita H 《Chemical & pharmaceutical bulletin》2008,56(10):1436-1437
A total synthesis of (+)-bakkenolide-A was carried out via the key intermediate 4, which was prepared based on an asymmetric cyclization-carbonylation reaction established in our laboratory. Diastereoselective construction of the spirolactone moiety was achieved using Mitsuhashi's protocol as a key step. 相似文献
106.
Furutachi H Hashimoto K Nagatomo S Endo T Fujinami S Watanabe Y Kitagawa T Suzuki M 《Journal of the American Chemical Society》2005,127(13):4550-4551
A mononuclear iron(III) complex containing a peroxocarbonate ligand, [Fe(qn)2(O2C(O)O)]- (qn = quinaldinate), underwent the reversible O-O bond cleavage and reformation of the peroxo group via the formation of FeIV=O or FeV=O species, which was confirmed by the resonance Raman and ESI-TOF/MS measurements. 相似文献
107.
Kano T Yamaguchi Y Tokuda O Maruoka K 《Journal of the American Chemical Society》2005,127(47):16408-16409
A direct asymmetric Mannich reaction using a novel axially chiral amino trifluoromethanesulfonamide (S)-3 has been developed in highly anti-selective and enantioselective manners. Thus, in the presence of a catalytic amount of (S)-3, the reactions between aldehydes and the alpha-imino ester 4 proceed smoothly to give the functional beta-amino aldehydes with significantly higher anti/syn ratio and enantioselectivity than previously possible. 相似文献
108.
109.
Masanobu Uchiyama Yasushi Takamatsu Kentaro Ogata Taichi Matsumoto Shiro Jimi Kazuo Tamura Shuuji Hara 《Biomedical chromatography : BMC》2013,27(7):818-820
A practical high‐performance liquid chromatography using a Cosmosil HILIC column and UV detection was developed for determining the concentrations of cytosine arabinoside (Ara‐C) and uracil arabinoside (Ara‐U), which is a major metabolite of Ara‐C, in human plasma. This method was used to determine the plasma concentrations of Ara‐C and Ara‐U in a patient treated with high‐dose Ara‐C therapy for end‐stage renal failure. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
110.