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排序方式: 共有176条查询结果,搜索用时 296 毫秒
81.
A sample of 115 Ke4+(e+) decays has been obtained in a heavy liquid bubble chamber. The decay rate is given, together with the form-factors and mean ππ phase-shift as determined by a maximum likelihoog method. 相似文献
82.
Jan A BartenAlexander A Kadyrov Enno LorkGerd-Volker Röschenthaler 《Journal of fluorine chemistry》2002,116(1):87-92
Selected imines and one bis-imine react via their enamine tautomers with terminal perfluorinated epoxides, e.g. hexafluoropropene oxide to produce fluorinated enamino ketones or imino ketones. In contrast, internal perfluorinated linear epoxides and one cyclic epoxide yield intermediate imino alcohols, which in one case added hexafluoroacetone, furnishing a new imino diol investigated by X-ray diffraction. 相似文献
83.
Rüdiger Mews Tobias Borrmann Enno Lork Jan Petersen Wolf-Dieter Stohrer Paul G. Watson 《Journal of fluorine chemistry》2004,125(11):1649-1655
One of the most interesting compounds in sulfur nitrogen fluorine chemistry is NSF2NS(O)F2 (3) (reported by Glemser and Höfer 30 years ago): in the NS backbone a triple and a double bond are connected by a single bond. Electrophiles (metal cations, fluoro Lewis acids, “CH3+”) attack this multifunctional system exclusively at the thiazyl nitrogen of the triple bond. [M(NSF2NS(O)F2)4][AsF6]2 (M = Ni (4b), Cu (4c)), [Re(CO)5(NSF2NS(O)F2)][AsF6]− (5), F5A·NSF2NS(O)F2 (A = As (6), Sb (7)), F3B·NSF2NS(O)F2 (8) and [H3CNSF2NS(O)F2]+[AsF6]− (9) were isolated. The X-ray structures of 4c, 6, 8 and 9 are reported, bonding in these complexes is compared with the recently reported related NSAr2NS(X)Ar2 (X = O, NH) species. 相似文献
84.
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86.
Enno LorkRüdiger Mews Makhmut M. ShakirovPaul G. Watson Andrey V. Zibarev 《Journal of fluorine chemistry》2002,115(2):165-168
The first AlkNSNHetF sulfur diimide 6 (Alk=adamant-1-yl, HetF=2,3,5,6-tetrafluoropyrid-4-yl) was prepared by trapping of the corresponding alkylthiazylamide [AlkNSN]−3 with pentafluoropyridine, followed by X-ray structural characterization. For 6, the Z,E configuration was found. From the reaction of 3 with octafluoronaphthalene, hexafluorinated naphthothiadiazole 7 was isolated along with the parent AlkNH2. 相似文献
87.
Makarov AY Irtegova IG Vasilieva NV Bagryanskaya IY Borrmann T Gatilov YV Lork E Mews R Stohrer WD Zibarev AV 《Inorganic chemistry》2005,44(20):7194-7199
[1,2,5]Thiadiazolo[3,4-c][1,2,5]thiadiazole (1) is synthesized in 62% yield by fluoride ion-induced condensation of 3,4-difluoro-1,2,5-thiadiazole with (Me(3)SiN=)(2)S. The reversible electrochemical reduction of 1 leads to the long-lived [1,2,5]thiadiazolo[3,4-c][1,2,5]thiadiazolidyl radical anion (2) and further to the dianion (3). The radical anion 2 is also obtained by the chemical reduction of the precursor 1 with t-BuOK in MeCN. The radical anion 2 is characterized by ESR spectroscopy in solution and in the crystalline state. The stable salts [K(18-crown-6)][2] and [K(18-crown-6)][2].MeCN (8 and 9, respectively) are isolated from the spontaneous decomposition of the [K(18-crown-6)][PhXNSN] (6, X = S; 7, X = Se) salts in MeCN solution followed by XRD characterization. The radical anion 2 acts as a bridging ligand in 8 and as chelating ligand in 9. The structural changes observed by XRD in going from 1 to 2 are explained by means of DFT/(U)B3LYP/6-311+G calculations. 相似文献
88.
Kingston M Chen SJ Lork E Mews R 《Dalton transactions (Cambridge, England : 2003)》2004,(9):1400-1404
The synthesis of TAS+ C3N3F4- (1) (TAS+ = (Me2N)3S+) and the reactions of 1 with Me3SiOSiMe3 and Me3SiCF3 to give TAS+ C3N3F2O- (2) and TAS+[(NCF)(NCCF3)(NC(CF3)(2)]- (4) are reported. An isomer of 4, TAS+[(NCCF3)2(NCFCF3)]-, compound 6, was obtained by fluoride ion addition to (CF3CN)3. From the reactions with Me3SiNMe2 neutral fluoroamino triazines C3N3Fn(NMe2)(n-1) (n = 1, 2) were isolated. Possible reaction pathways are discussed, the X-ray structures of 1, 2, 4 and 6 were determined. 相似文献
89.
Dr. Gesa Schäfer Dr. Jelena Milić Dr. Adeeb Eldahshan Dr. Frank Götz Dr. Kerstin Zühlke Christian Schillinger Annika Kreuchwig Dr. Jonathan M. Elkins Kamal R. Abdul Azeez Andreas Oder Dr. Marie C. Moutty Nanako Masada Monika Beerbaum Brigitte Schlegel Sylvia Niquet Dr. Peter Schmieder Dr. Gerd Krause Dr. Jens Peter von Kries Prof. Dermot M. F. Cooper Prof. Dr. Stefan Knapp Prof. Jörg Rademann Prof. Dr. Walter Rosenthal Priv.‐Doz. Dr. Enno Klussmann 《Angewandte Chemie (International ed. in English)》2013,52(46):12187-12191
90.
Dmitri V. Sevenard Olesya Kazakova Ralf-Matthias Schoth Enno Lork Gerd-Volker Röschenthaler 《Journal of chemical crystallography》2011,41(12):1795-1799