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排序方式: 共有355条查询结果,搜索用时 15 毫秒
1.
2.
H. Katsurada 《Journal of Number Theory》2004,104(1):100-117
We introduce a formula for the p-adic Siegel-Eisenstein series which demonstrates a connection with the genus theta series and the twisted Eisenstein series with level p. We then prove a generalization of Serre's formula in the elliptic modular case. 相似文献
3.
We have studied the algorithm for the automatic chromatic dispersion compensation using bit error rate (BER) and Q-factor optimization for realization of dynamically reconfigurable all-optical network. We have made sure good performance using the compensation system by laboratory experiments. 相似文献
4.
Hidenori Hanaoka Yuka Imamoto Takahiro Hino Tetsuya Kohno Kazunori Yanagi Yoshiaki Oda 《Journal of polymer science. Part A, Polymer chemistry》2007,45(16):3668-3676
Chromium catalysts combined with phosphorous‐bridged bisphenoxy ligands were found to be highly active for ethylene polymerization. The most efficient catalyst precursor among them, generated by combining bis[3‐tert‐butyl‐5‐methyl‐2‐hydroxyphenyl](phenyl)phosphine hydrochloride ( 1a ) and CrCl3(THF)3, was characterized. X‐ray analysis of (3‐tert‐butyl‐5‐methyl‐2‐phenoxy)(3‐tert‐butyl‐5‐methyl‐ 2‐hydroxyphenyl)(phenyl)phosphine bis(tetrahydrofuran)chromium dichloride ( 6 ), obtained by the reaction of 1a and CrCl3(THF)3 in the presence of NaH, revealed a unique structure in which one phenol moiety of the bisphenol did not coordinate to the chromium center. Complex 6 showed higher activities than those observed in the in situ catalyst system. Polyethylene of various molecular weights was obtained with differing activators. The highest activity (113.5 kg mmol (cat)?1 h?1) was observed when TIBA/TB was used as a cocatalyst. A medium molecular weight polymer with narrow molecular weight distribution (Mw = 128,700, Mw/Mn = 1.8) was obtained using a 6 ‐TIBA/B(C6F5)3 system. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3668–3676, 2007 相似文献
5.
Various N-sulfenyl heterocycles were synthesized by transamination of sulfenamides using a chlorine gas-free method. The N-sulfenyl heterocycles behaved as sulfenylating reagents of anilines; N-sulfenylbenzimidazoles were the most effective. 相似文献
6.
Practical asymmetric synthesis of (S)-MA20565, a wide-spectrum agricultural fungicide 总被引:1,自引:0,他引:1
Tanaka K Katsurada M Ohno F Shiga Y Oda M Miyagi M Takehara J Okano K 《The Journal of organic chemistry》2000,65(2):432-437
A practical asymmetric synthesis of a wide-spectrum agricultural fungicide, (S)-MA20565 (1), is described. The convergent synthesis was achieved starting from commercially available 3-(trifluoromethyl)aniline (7) in 44% overall yield through five steps and 2-bromobenzaldehyde (9) in 48% overall yield through four steps, respectively. (S)-O-[1-(3-Trifluoromethylphenyl)ethyl]hydroxylamine (2), a key intermediate of 1, was prepared via ruthenium(II)-catalyzed asymmetric transfer hydrogenation of 1-(3-trifluoromethylphenyl)ethanone (6) followed by chlorination using methanesulfonyl chloride and oxyamination using potassium acetohydroxamate with high level of stereocontrol. 相似文献
7.
Tatsuro Ouchi Hirotoshi Fujie Satoshi Jokei Yoshiomi Sakamoto Hidenori Chikashita Takeshi Inoi Otto Vogl 《Journal of polymer science. Part A, Polymer chemistry》1986,24(9):2059-2074
Acryloyl-type polymer fixing 1-β-carbonylethyl-5-fluorouracil residues through D -glucofuranoses via ester bonds was synthesized by means of polymerization of the corresponding monomer and polymer reaction. In order to provide the water-soluble objective polymer, the copolymerization of the acryloyl-type monomer with acrylamide was carried out. The extent of release of 5-FU residues from the copolymer was investigated in the enzyme or nonenzyme system in vitro. Furthermore, the antitumor activities of the water-insoluble homopolymer and water-soluble copolymer obtained were tested in vivo. 相似文献
8.
Masatoshi Sakae Masanori Katsurada Mayumi Watanabe Fumio Yoneda Sadao Nishigaki Toshimasa Ishida 《Journal of heterocyclic chemistry》1997,34(1):157-160
The reaction of 2-bromoethylamine 1 with methylisothiocyanate 2 under mild condition gave 2-methyl-amino-2-thiazoline 3 as the major product together with two kinds of byproducts, 3-(N-methylthiocar-bamoyl)-2-methyliminothiazolidine 4 and N,N′-dimethyl-N-(2-thiazolin-2-yl)thiourea 5. Thermal isomer-ization of 5 to 4 was observed. The structures of the byproducts were confirmed by X-ray crystallography. 相似文献
9.
[reaction: see text] An aqueous biphasic reaction system enables the direct use of allyl alcohol in the Tsuji-Trost reaction without the help of any activating reagents for allyl alcohol. The reaction conditions are neutral to basic, allowing the use of amines as the nucleophile. Theoretical calculations have elucidated the importance of hydration of the hydroxy group for the smooth generation of pi-allylpalladium species. 相似文献
10.
Hidenori Somei 《Tetrahedron letters》2004,45(9):1841-1844
A new concept of dual activation catalysis in homolytic coupling reaction of 2-naphthol derivatives is described. The dinuclear vanadium(IV) catalyst (R,S,S)-1a promotes the oxidative coupling reaction of 2-naphthol derivatives with high reactivity and enantioselectivity. This dual activation mechanism is supported by the fact that the reaction rate of oxidative coupling of 2-naphthol promoted by the (R,S,S)-1a is 48 times faster than that of the mononuclear complex (S)-3 and a lower catalyst loading of (R,S,S)-1a shows higher catalyst efficiency both in enantioselectivity and chemical yield. 相似文献