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11.
The reaction of 5a-acetyl-6-ethoxycarbonyl-5a,6a-dihydro-6H-cyclopropa[e]pyrazolo[1,5-a]pyrimidine-3-carbonitrile ( 1a ) with benzylamine gave ethyl l-benzyl-5-cyano-8a,9-dihydro-2-methyl-1H-pyrrolo[3,4-e]-pyrazolo[1,5-a]pyrimidine-8a-carboxylate ( 2a ), in addition to 5-acetyl-3-benzylamino-1-(4-cyanopyrazol-3-yl)- 2-pyridone ( 3 ). Reaction of 1a with aniline gave ethyl 6-acetyl-8-anilino-3-cyano-7,8-dihydro-4H-pyrazolo-[1,5-a][1,3]diazepine-8-carboxylate ( 4 ), in addition to ethyl 3-cyano-7-methyl-6-pyrazolo[1,5-a]pyrimidine-acrylate ( 5 ). On the other hand, the same reactions of 1b with benzylamine or aniline gave 2b or 8b , respectively. Though catalytic hydrogenation of 1a over 5% palladium-carbon proceeded by ring fission of cyclopropane ring to give 9 , 1a (or 1b ) afforded 4,5-dihydro derivatives ( 13 or 15 ) by catalytic hydrogenation over platinum oxide. The reactivity of 5-methoxy-4,5,5a,6a-tetrahydro-6H-cyclopropa[e]pyrazolo[1,5-a]pyrimidine ( 16 ), which are related analogs of 1a,b , is also described. 相似文献
12.
13.
Ammonium aromatic diselenoates were synthesized by reacting aromatic diselenoic acid 2-(trimethylsilyl)ethyl esters derived from aluminum 2-(trimethylsilyl)ethyl selenolate with aromatic selenoic acid O-methyl esters with ammonium fluorides. The results of molecular structure analysis and NMR studies of ammonium salts supported the double-bond character between the carbon atom and selenium atoms. 相似文献
14.
Tachi Y Aita K Teramae S Tani F Naruta Y Fukuzumi S Itoh S 《Inorganic chemistry》2004,43(15):4558-4560
A dicopper(I) complex supported by a novel asymmetric pentapyridine dinucleating ligand, consisting of tetradentate and tridentate metal-binding sites, has been synthesized and characterized. The dicopper(I) complex reacted with molecular oxygen at a low temperature to give an unprecedented mu-peroxo dicopper(II) complex presumably having a mu-eta1:eta2 binding mode, the spectroscopic features and the reactivity of which have been explored in detail. 相似文献
15.
Catalytic activities of the reaction products of diethylzinc or triethylaluminum with primary amines in the polymerization of propylene oxide were studied. Generally, organozinc compounds give higher ratio of the crystalline to the amorphous polymer than the organoaluminums. In the reactions of organometallic compounds with primary amines, Et2AlNPhAlEt2, Et2AlN-t-BuAlEt2, EtZnNH-t-Bu, and EtZn-t-BuZnEt were isolated in crystalline state. EtZnN-t-BuZnEt proved to be an excellent catalyst for the stereospecific polymerization of propylene oxide and forms coordination complexes with some electron donors such as dioxane, pyridine, epichlorohydrin and propylene oxide. The propylene oxide complex is unstable in solution and decomposes at temperatures above room temperature to give poly(propylene oxide), while the pyridine complex has no catalytic activity. Therefore, it is concluded that the polymerization of propylene oxide with this catalyst proceeds through the coordination of propylene oxide to the zinc atom of the catalyst. 相似文献
16.
17.
Shintaro Wakamatsu Yuka Takahashi Dr. Hidetsugu Tabata Dr. Tetsuta Oshitari Norihiko Tani Prof. Dr. Isao Azumaya Dr. Yukiteru Katsumoto Dr. Takeyuki Tanaka Dr. Shinzo Hosoi Prof. Dr. Hideaki Natsugari Prof. Dr. Hideyo Takahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(22):7056-7063
The stereochemistry around the N‐benzoylated indole moiety of indometacin was studied by restricting the rotation about the N? C7′ and/or C7′? C1′ bond. In the 2′,6′‐disubstituted ones, an atropisomeric property was found and the atropoisomers were separated and isolated as stable forms. Their biological abilities to inhibit cyclooxygenase‐1 (COX‐1) and cyclooxygenase‐2 (COX‐2) were examined. Only the aR‐isomer showed specific inhibition of COX‐1, and COX‐2 was not inhibited by either atropisomer. Conformational analysis in NMR studies and X‐ray crystallography, and CD spectra in combination with calculations were utilized to elucidate the bioactive conformations. 相似文献
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19.
Homogeneous ZnO Nanoparticles by Flame Spray Pyrolysis 总被引:2,自引:0,他引:2
Zinc oxide (ZnO) nanoparticles were made by flame spray pyrolysis (FSP) of zinc acrylate–methanol–acetic acid solution. The effect of solution feed rate on particle specific surface area (SSA) and crystalline size was examined. The average primary particle diameter can be controlled from 10 to 20nm by the solution feed rate. All powders were crystalline zincite. The primary particle diameter observed by transmission electron microscopy (TEM) was in agreement with the equivalent average primary particle diameter calculated from the SSA as well as with the crystalline size calculated from the X-ray diffraction (XRD) patterns for all powders, indicating that the primary particles were rather uniform in diameter and single crystals. Increasing the solution feed rate increases the flame height, and therefore coalescence and/or surface growth was enhanced, resulting in larger primary particles. Compared with ZnO nanoparticles made by other processes, the FSP-made powder exhibits some of the smallest and most homogeneous primary particles. Furthermore, the FSP-made powder has comparable BET equivalent primary particle diameter with but higher crystallinity than sol–gel derived ZnO powders. 相似文献
20.
Kon N Takemura H Otsuka K Tanoue K Nakashima S Yasutake M Tani K Kimoto J Shinmyozu T Inazu T 《The Journal of organic chemistry》2000,65(12):3708-3715
Macropolycyclic cage compounds were synthesized by a direct reaction between diamines and bis(bromomethyl) compounds. The procedure for constructing the polycyclic cage structure is simple and straightforward. The macropolycyclic compounds obtainable from this cyclization procedure are three-dimensional cage compounds, and any other isomers were not obtained except for two examples. Benzene, pyridine, and aliphatic units could be introduced into the cage structure. The macrocycles that have strong cation affinity were obtained as their potassium complexes. 相似文献