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91.
92.
Takeo Taguchi Ginjiro Tomizawa Akihiro Kawara Masaharu Nakajima Yoshiro Kobayashi 《Journal of fluorine chemistry》1988,40(2-3):171-182
Reaction of 1-phenylsulfonul-3,3,3-trifluoropropene(1) with carbonyl-stabilized enolate anions smoothly proceeded to give the addition products(7) in good yield while with an alkyl-lithium or Grignard reagent the formation of the vinyl anion(8) was one of the reaction pathways. Reaction of 1 with the chiral nucleophiles(11, 16) was carried out to give the functionalized trifluoromethylated compounds(13, 7b) in 4-43% ee 相似文献
93.
The basic characteristics of vaporization and flowing behavior of n-pentane injected through a single nozzle into a column of hot water have been studied photographically. Subcools at the nozzle-outlet have a strong influence on the critical temperature driving forces at over which vaporization can be maintained. The length of a Rayleigh jet is remarkably shortened when vaporization occurs, whereas mean diameters of drops are little affected whether vaporization occurs or not. A specific condition that a bubble appears in each drop is satisfied not on a specific line but over a wide region on the ΔT∞ - UN plane. 相似文献
94.
95.
Yoshiro Kobayashi Takaharu Nakano Masahura Nakajima Itsumaro Kumadaki 《Tetrahedron letters》1981,22(12):1113-1114
A new valence-bond isomer of pentakis(trifluoromethyl)-1,3-diazepine was synthesized from tris(trifluoromethyl)cyclopropenyl trifluoromethyl ketone, and reacted with diazomethane to give an N-methylated product. 相似文献
96.
Eishun Tsuchida Shinichi Irie 《Journal of polymer science. Part A, Polymer chemistry》1973,11(4):789-799
In order to discuss the electrostatic-field effect on a polymer reaction, the quaternization of poly-4-vinylpyridine–benzyl chloride (system I) was compared to that of poly-γ-chloromethylstyrene–γ-picoline (system II). In these two systems, the reaction initially proceeded according to the simple second-order kinetics. However, after the degree of quaternization exceeded 20–30 mole-%, a deviation from simple second-order kinetics occurred. In system I negative deviation occurred, while in system II positive deviation occurred. These phenomena occurred even though the solvent or the initial concentrations of the reactants were changed. The reasons for these phenomena are given below. In system I, the quaternized pyridine nitrogens prevented the benzyl chloride from approaching the unquaternized pyridine nitrogens. However, in system II the free γ-picoline was attracted by the quaternized chloro-γ-methyl site. Furthermore, the point at which the deviation occurred was determined by the degree of chloromethylation. All these results suggest that the effect of an electrostatic field must be presumed in these two systems. 相似文献
97.
98.
Full-color photochromism of a fused dithienylethene trimer 总被引:1,自引:0,他引:1
Higashiguchi K Matsuda K Tanifuji N Irie M 《Journal of the American Chemical Society》2005,127(25):8922-8923
A diarylethene fused trimer, 1-(5-(2-(3,5-dimethyl-2-thienyl)hexafluorocyclopententen-1-yl)-2,4-dimethyl-3-thienyl)-2-(5-(2-(2,4-dimethyl-5-phenyl-3-thienyl)hexafluorocyclopentene-1-yl)-2,4-dimethyl-3-thienyl)hexafluorocyclopentene, was synthesized. The diarylethene derivative showed full-color photochromic performance by choosing appropriate wavelength of light. 相似文献
99.
Kuroki L Takami S Shibata K Irie M 《Chemical communications (Cambridge, England)》2005,(48):6005-6007
Although dioxazolylethene 1a did not show any photocoloration in the single crystalline phase, 1a displayed photochromism in the mixed crystal containing both 1a and dithiazolylethene 2a ; the mixed crystal changed color from colorless to red, orange, and yellow upon irradiation with light of appropriate wavelengths. 相似文献
100.