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101.
Nelly Konopik 《Fresenius' Journal of Analytical Chemistry》1956,154(2):147-148
Ohne Zusammenfassung 相似文献
102.
A. Stock und Nelly Neuenschwander-Lemmer 《Fresenius' Journal of Analytical Chemistry》1941,122(7-8):294-298
Ohne Zusammenfassung 相似文献
103.
[reaction: see text] The complexes [PdCl2L2], where L is a crown-ether-containing triarylphosphane, catalyze the formation of biaryls from arylsiloxanes and aryl bromides with high yields in water as solvent and under air. The water-insoluble catalysts [PdCl2(PhCN)2] and [PdCl2(PPh3)2] are also efficient, although they decompose more quickly to form black Pd0. 相似文献
104.
105.
The syntheses of 2‐bromopyrazine, 2,4‐dibromopyrimidines, and 3‐bromo‐6‐phenylpyrazine were improved and their metalation with lithium alkylamides was studied. 相似文献
106.
Junting Wang Fernando Gordillo Gámez Jose Marín-Beloqui Aitor Diaz-Andres Dr. Xiaohe Miao Prof. David Casanova Prof. Juan Casado Dr. Junzhi Liu 《Angewandte Chemie (International ed. in English)》2023,62(10):e202217124
Incorporating non-hexagonal rings into polycyclic conjugated hydrocarbons (PCHs) can significantly affect their electronic and optoelectronic properties and chemical reactivities. Here, we report the first bottom-up synthesis of a dicyclohepta[a,g]heptalene-embedded PCH ( 1 ) with four continuous heptagons, which are arranged in a “Z” shape. Compared with its structural isomer bischrysene 1 R with only hexagonal rings, compound 1 presents a distinct antiaromatic character, especially the inner heptalene core, which possesses clear antiaromatic nature. In addition, PCH 1 exhibits a narrower highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap than its benzenoid contrast 1 R , as verified by experimental measurements and theoretical calculations. Our work reported herein not only provides a new way to synthesize novel PCHs with non-alternant topologies but also offers the possibility to tune their electronic and optical properties. 相似文献
107.
Ezzaher S Capon JF Gloaguen F Pétillon FY Schollhammer P Talarmin J Pichon R Kervarec N 《Inorganic chemistry》2007,46(9):3426-3428
Treatment of [Fe2(mu-pdt)(CO)6] [pdt=S(CH2)3S] with dppe (Ph2PCH2CH2PPh2) in refluxing toluene affords the asymmetric complex [Fe2(mu-pdt)(CO)4(dppe)] (1). Protonation of 1 with HBF4-Et2O in CH2Cl2 gives at room temperature the mu-hydrido derivative [Fe2(mu-pdt)(CO)4(dppe)(mu-H)](BF4) (2). Monitoring the reaction by 1H, 31P, and 13C NMR at low temperature reveals unambiguously that the process of the protonation of 1 implies terminal hydride intermediates. 相似文献
108.
Ruth Gordillo 《Journal of separation science》2021,44(1):448-463
While supercritical fluid chromatography was developed over 50 years ago, it is only over the past 15 to 20 years that it has become routinely utilized. Along with the commercialization of a new generation of instruments, during the last 20 years supercritical fluid chromatography has improved performance, reliability, and robustness. Supercritical fluid chromatography is fully compatible with mass spectrometric techniques. This review compiles the application of supercritical fluid chromatography separations coupled to mass spectrometry instrumentation for the exploration, profiling, and quantitation of metabolites during the last two decades. The selection of metabolites chosen for this article have direct applications in preclinical models of disease and clinical applications as potential biomarkers of disease including lipids, steroid hormones, bile acids, polar metabolites, peptides, and proteins. 相似文献
109.
We study a singular perturbation type minimization problem with a mass constraint over a domain in ℝ
N
, involving a potential vanishing on two curves in the plane. We demonstrate how the behavior of the minimizers depends on
the geometry of the domain and, more precisely, on its isoperimetric profile. 相似文献
110.