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11.
Kunihisa Yoshida Yoshimasa Toyo-Oka Kazusada Takeda 《Journal of heterocyclic chemistry》1995,32(2):701-702
The electrooxidation of 1-methylpyrazole in methanol containing sodium cyanide produced 1-methyl-pyrazole-4-carbonitrile 2 and ?5-carbonitrile 3 in yields of 23 and 8%, respectively (2e-oxidation products), together with 4-methoxy-1-methylpyrazole-5-carbonitrile 4 (4e-oxidation product, 4%). 相似文献
12.
[reaction: see text] A rhenium complex, [ReBr(CO)(3)(thf)](2), catalyzed the intermolecular reactions of 1,3-dicarbonyl compounds with terminal acetylenes and gave the corresponding alkenyl derivatives in excellent yields. These reactions could apply to an intramolecular version and gave the corresponding cyclic compounds quantitatively. 相似文献
13.
14.
15.
Complexes of the type (n-C
n
H2n
+1NH3)2SnX6 (0n 4 and X=Cl or Br) have been investigated with a variety of physico-chemical techniques. The structural phase transitions were found in some of these complexes. The temperature dependence of the Mössbauer spectral absorption area for (C2H5NH3)2SnCl6 and (C2H5NH3)2SnBr6 changed sharply at phase transition temperatures. The temperature dependences for (n-C4H9NH3)2SnCl6 and (n-C4H9NH3)2SnBr6 decreased gradually with an increase in temperature. The correlation between the temperature dependence of the spectral absorption area and the motion of n-C
n
H2n+1NH3
+ ions is discussed. 相似文献
16.
Tetsuo Suami Hiroaki Sasai Kazuhiro Matsuno Nobuo Suzuki Yoshimasa Fukuda Osamu Sakanaka 《Tetrahedron letters》1984,25(40):4533-4536
Tunicamycins and their eight analogs have been synthesized by condensation of a N-acetyl-D-glucosamine derivative and an anomeric chloride of tunicaminyl uracil, followed by deprotections and N-acylation. 相似文献
17.
自行研制了电子碰撞离子化的飞行时间型质量分析器(TOFMS),用于物质的化学分析。用研制的TOFMS测量了Ar离子化的飞行时间谱和离子的部分电离截面积比与碰撞电子能量的依赖关系,将它与Stepshan等人的实验结果进行了比较。 相似文献
18.
The resonance Raman spectra of tris(acetylacetonatoiron(III)) and ruthenium(III) complexes in various solvents and in water-acetonitrile (W-AN) mixtures were measured. The resonance Raman spectra of both complexes indicated peaks near 460 and around 1580 cm–1. Thev(C-O) peak (around 1580 cm–1) is shifted to low frequency with an increase in the dielectric constant T of the solvents, whereas thev(M-O) (M=Fe and Ru, near 460 cm–1) are constant, independent of T. It implies that the C-O bond in the acac– ligand is lengthened by the polarizability effect of the solvents, while both the Fe-O and Ru-O bonds, which are located in the inside of the complexes, are not influenced by the solvents indicating that the interaction does not depend on the properties of individual solvent molecules but on those of the aggregate. 相似文献
19.
Shunichi Manabe Kazumasa Wakamatsu Yoshimasa Hirata Kiyoyuki Yamada 《Tetrahedron》1979,35(16):1925-1929
13C NMR spectra are reported for derivatives of toxic sesquiterpenes, anisatin (I) and neoanisatin (II). Chemical shifts for each compound have been assigned on the basis of off-resonance decoupling experiments, known chemical shift rules, and comparison of the spectra among the compounds examined. Toxic anisatin (I) is known to isomerize under mild conditions to a non-toxic compound, anisatinic acid. The structure of anisatinic acid has been determined unambiguously to be IIIa by the 13C NMR spectral analysis of a derivative 8 of anisatinic acid. Some aspects of the substituent effects on the 13C chemical shifts obtained in the present investigation are described. 相似文献
20.
The catalyst comprised [PdCl(η3-C3H5)]2 and a simple chiral hemilabile ferrocene ligand, 1′,2-bis(diphenylphosphinoethyl)ferrocenyl alcohol, provides synthetically acceptable results for an enantioselective Pd-catalyzed allylic alkylation of cyclohexanone derivatives bearing an electron-withdrawing group at the α-position to form the quaternary carbon with up to 90% enantioselectivity under mild reaction conditions. 相似文献