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841.
Sankar Hajra 《中国物理 B》2014,(9):129
We point out an error in Eq.(19) in our original paper [Chin. Phys. B 23 040402(2014)] and present the correct equation. 相似文献
842.
843.
Dr. Debangsu Sil Firoz Shah Tuglak Khan Prof. Dr. Sankar Prasad Rath 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14585-14597
The synthesis, structure, and properties of bischloro, μ‐oxo, and a family of μ‐hydroxo complexes (with BF4?, SbF6?, and PF6? counteranions) of diethylpyrrole‐bridged diiron(III) bisporphyrins are reported. Spectroscopic characterization has revealed that the iron centers of the bischloro and μ‐oxo complexes are in the high‐spin state (S=5/2). However, the two iron centers in the diiron(III) μ‐hydroxo complexes are equivalent with high spin (S=5/2) in the solid state and an intermediate‐spin state (S=3/2) in solution. The molecules have been compared with previously known diiron(III) μ‐hydroxo complexes of ethane‐bridged bisporphyrin, in which two different spin states of iron were stabilized under the influence of counteranions. The dimanganese(III) analogues were also synthesized and spectroscopically characterized. A comparison of the X‐ray structural parameters between diethylpyrrole and ethane‐bridged μ‐hydroxo bisporphyrins suggest an increased separation, and hence, less interactions between the two heme units of the former. As a result, unlike the ethane‐bridged μ‐hydroxo complex, both iron centers become equivalent in the diethylpyrrole‐bridged complex and their spin state remains unresponsive to the change in counteranion. The iron(III) centers of the diethylpyrrole‐bridged diiron(III) μ‐oxo bisporphyrin undergo very strong antiferromagnetic interactions (J=?137.7 cm?1), although the coupling constant is reduced to only a weak value in the μ‐hydroxo complexes (J=?42.2, ?44.1, and ?42.4 cm?1 for the BF4, SbF6, and PF6 complexes, respectively). 相似文献
844.
Selective Oxidation of Alkyl‐Substituted Polyaromatics Using Ruthenium‐Ion‐Catalyzed Oxidation 下载免费PDF全文
Ewa Nowicka Meenakshisundaram Sankar Robert L. Jenkins David W. Knight David J. Willock Graham J. Hutchings Manuel Francisco Stuart H. Taylor 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4285-4293
Ruthenium‐ion‐catalyzed oxidation of a range of alkylated polyaromatics has been studied. 2‐Ethylnaphthalene was used as a model substrate, and oxidation can be performed in either a conventional biphasic or in a monophasic solvent system. In either case the reaction rates and product selectivity are identical. The reaction products indicate that the aromatic ring system is oxidized in preference to the alkyl chain. This analysis is possible due to the development of a quantitative NMR protocol to determine the relative amounts of aliphatic and aromatic protons. From a systematic set of substrates we show that as the length of the alkyl chain substituent on a polyaromatic increases, the proportion of products in which the chain remains attached to the aromatic system increases. Larger polyaromatic systems, based on pyrene and phenanthrene, show greater reactivity than those with fewer aromatic rings, and the alkyl chains are more stable to oxidation. 相似文献
845.
Cover Picture: Selective Oxidation of Alkyl‐Substituted Polyaromatics Using Ruthenium‐Ion‐Catalyzed Oxidation (Chem. Eur. J. 11/2015) 下载免费PDF全文
846.
847.
Novel 2‐alkylcarbamato/thiocarbama‐to‐2,3‐dihydro‐5‐propylthio‐1H‐1,3,2‐benzodiazaphos‐phole 2‐oxides ( 4a–J ) were synthesized by cyclization of 4‐propylthio‐1,2‐phenylenediamine ( 3 ) with the corresponding dichlorophosphoryl carbamates/thiocarbamates ( 2a–J ) that were obtained by the addition of alcohols/thiols to isocyanatophosphoryl dichloride ( 1 ). The structures of the title compounds were confirmed by the 1H, 13C, 31P NMR, and mass spectral studies. Some of these products were found to possess significant antimicrobial activity. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:336–340, 2000 相似文献
848.