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排序方式: 共有2621条查询结果,搜索用时 31 毫秒
31.
Kazuhiro Kobayashi Atsushi Takanohashi Kenichi Hashimoto Osamu Morikawa Hisatoshi Konishi 《Tetrahedron》2006,62(44):10379-10382
A facile synthetic method for 4,5-diaminopyrrolo[1,2-a]quinoline derivatives has been developed. Treatment of 2-(pyrrol-1-yl)benzaldehydes with secondary amine hydrochloride/NaI/TMSCl/Et3N in the presence of an isocyano compound leads to the formation of 4-alkyl(or aryl)amino-5-dialkylaminopyrrolo[1,2-a]quinolines. 相似文献
32.
Ken-Ichi Ito Masamichi Nishimura Minoru Sashio Masahiro Tsunooka 《Journal of polymer science. Part A, Polymer chemistry》1994,32(11):2177-2185
It was found that amines were formed efficiently by the photolysis of O-acyloximes followed by hydrolysis in polystyrene films and the relationship between structures of O-acyloximes and yields of amines were investigated. O-phenylacetyl acetophenone oxime (PaApO), O-pivaloyl acetophenone oxime (PApO), and O-benzoyl acetophenone oxime (BApO) as monofunctional O-acyloximes and O,O′-succinyl diacetophenone oxime (SDApO) and O,O′-glutaryl diacetophenone oxime (GDApO) as bifunctional O-acyloximes were examined. The yields of amines for PaApO and SDApO under N2 were ca. 70%, which was the highest among O-acyloximes examined in this experiment. On the other hand, the yields for PApO, BApO, and GDApO were less than 15% and it was verified that the hydrogen abstraction by imino radicals via 6-membered cyclic intermediates resulted in the lowering of yields. Although the effect of oxygen under photolysis on the yields of amine for PaApO was negligible under 50% conversion of PaApO, the yield decreased with further increase in the conversion and was 50% at 90% conversion. © 1994 John Wiley & Sons, Inc. 相似文献
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Hideki Namba Okihiro Tokunaga Tadashi Tanaka Yoshimi Ogura Shinji Aoki Ryoji Suzuki 《Radiation Physics and Chemistry》1993,42(4-6):669-672
The fundamental research work with simulated coal-fired flue gas was performed in JAERI to get basic data for electron beam treatment of flue gas from thermal power plants in Japan. The standard condition of the experiments was set to be the same as that of next large scale pilot test in Nagoya. The concentrations of NOx and SOx were 225 ppm and 800 ppm, respectively. The temperature of the system was 65°C. The effect of multiple irradiation was observed for NOx removal. The target SOx and NOx removals (94% and 80%, respectively) with low NH3 leakage (less than 10 ppm) were achieved at 9 kGy irradiation with 0.9 NH3 stoichiometry during 7 hours continuous operation. The facility for the pilot plant (12,000 Nm3/hr) has just built at the site of Shin-Nagoya power plant of Chubu Electric Power Company and will be started in full operation in November 1992. 相似文献
35.
Qiang Li Pingfan Wu Yongge Wei Hongyou Guo 《Journal of organometallic chemistry》2006,691(6):1223-1228
An organic-inorganic hybrid compound, (Bu4N)2[Mo6O18(NAr)] (Ar = p-BrC6H4) has been synthesized via the DCC dehydrating protocol of the reaction of [α-Mo8O26]4− with 4-bromoaniline hydrochloride in anhydrous acetonitrile, which has been characterized by UV-Vis spectra, 1H NMR and single crystal X-ray diffraction study. By comparing the UV-Vis spectra, which were used to monitor the reaction, the optimum preparative condition for this compound was also determined. This compound crystallizes in the monoclinic space group P21/n, which is featured in a terminal para-bromophenylimido group linked to an Mo atom of a hexamolybdate cluster by a Mo-N triply bond. In addition, there are π-π dimerization of the neighboring cluster anions though the parallel aromatic rings in their crystals. 相似文献
36.
An efficient method has been developed for one-pot three-component coupling reactions of various aldehydes, 1-cyclohexen-2-one, and primary or secondary amines in the presence of a catalytic amount of Yb(OTf)3 under mild conditions to afford the corresponding 2-arylmethyl N-substituted anilines in good yields. In addition, the catalyst was easily recovered and could be reused for at least four cycles without any loss of activity. 相似文献
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38.
An efficient route for the regio- and stereoselective ring opening of N-tosylaziridines with zinc dihalides (ZnX2, X = Cl, Br, I) is described. Depending on the solvent and Zn(II) halide, β-halo amines or imidazolines are obtained selectively in good to excellent yields. 相似文献
39.
脂肪族胺、醇和醚的气相质子亲合能(PA)与N, O原子所带电荷(qx)以及烷基的极化效应指数(PEI)的关系可表示为其中a、b、c为系数。回归分析结果表明, 上式较好地表达了脂肪族胺、醇和醚的气相碱性变化规律。 相似文献
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