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41.
The formation and crystal structures of bis(1‐naphthyl) diselenide ( 1 ) and bis{[2‐(N,N‐dimethylamino)methyl]phenyl} tetraselenide ( 2 ) are described. Whereas 1 can be produced in good yields, 2 is formed only as a minor product together with the known main product, bis{[2‐(N,N‐dimethylamino)methyl]phenyl} diselenide. The composition of the reaction mixture is semi‐quantitatively estimated by 77Se NMR spectroscopy and DFT calculations. The effect of the n2→σ*(Se–Se) and π→σ*(Se–Se) secondary bonding interactions on the Se–Se bonds is discussed both by DFT calculations and comparison with literature, as available. The bromination of 1 yields monomeric (1‐naphthyl)selenenyl bromide ( 3 ) in good yields. That of the reaction mixture of (C6H4CH2NMe2)Sex (x = 2–4) and Se8 afforded (C6H4CH2NMe2H)2[SeBr4] ( 4 ) and (C6H4CH2NMe2H)2[SeBr6] ( 5 ) in addition to (C6H4CH2NMe2)SeBr, which has been previously reported.  相似文献   
42.
43.
Copper indium diselenide (CIS) is a prime candidate as the absorber layer in solar cells for use in extraterrestrial environments due to its good photovoltaic efficiency and ability to resist radiation damage. While CIS-based devices have been tested extensively in the laboratory using electron and proton irradiation, there is still little understanding of the underlying mechanisms which give rise to its radiation hardness. To gain better insight into the response of CIS to displacing radiation, transmission electron microscope samples have been irradiated in situ with 400?keV Xe ions at the Intermediate Voltage Electron Microscope facility at Argonne National Laboratory, USA. At room temperature, dislocation loops were observed to form and grow with increasing fluence. These loops have been investigated using g ?·? b techniques and inside/outside contrast analysis. They have been found to reside on {112} planes and to be interstitial in nature. The Burgers vector were calculated as b ?=?1/6 ?221?. The compositional content of these interstitial loops was found to be indistinguishable from the surrounding matrix within the sensitivity of the techniques used. To facilitate this work, experimental electron-diffraction zone-axis pattern maps were produced and these are also presented, along with analysis of the [100] zone-axis pattern.  相似文献   
44.
45.
由酮合成对称二烃基二硒醚的新方法   总被引:1,自引:0,他引:1  
在正丁胺的催化下, 酮与硒氢化钠, 二硒化钠乙醇溶液通过"一锅"法反应得到了中等产率的二硒醚.  相似文献   
46.
A mild and convenient one-pot process for synthesizing alkyl phenyl selenides is developed using indium metal. The reaction shows the selectivity for tert-alkyl, benzylic, and allylic halides over primary and secondary alkyl halides.  相似文献   
47.
简便合成二酰基二硒醚   总被引:1,自引:0,他引:1  
芳基硒代酰胺与酰氯以1∶1的摩尔比在氯仿溶液中作用, 可以较高的产率得到二酰基二硒醚, 而芳基硒代酰胺与酰氯以1∶2的摩尔比反应时则生成二酰基硒醚. 提出了反应可能的机理.  相似文献   
48.
The intercalation of metallocenes (Cp2Co, Cp2Fe, and Cp2Ni, where Cp is η5-C5H5) from the gas phase into the TiSe2 lattice and of cobaltocene from solutions in acetonitrile, carbon tetrachloride, and chloroform into TiSe2 was studied. The insertion of metallocenes from the gas phase into the TiSe2 lattice gives rise to the TiSe2(Cp2M)0.3 compounds (M = Co or Fe) having the same stoichiometry. The reactions with the use of acetonitrile as the solvent for metallocenes, which facilitates the insertion, afford not only the intercalation complex but also the reaction product of metallocene and acetonitrile, viz., (η 5-C5H5)Co(η4-C5H5CH2CN) (1). In the reactions of cobaltocene with chloroform or carbon tetrachloride in the presence of titanium diselenide, only the addition product, viz., (η 5-C5H5)Co(η4-C5H5CCl3) (2), was isolated. The structures of complexes 1 and 2 were studied by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 876–880, May, 2007.  相似文献   
49.
The structures of the 18‐membered diselenide‐linked macrocycle 10,27‐di‐tert‐butyl 11,28‐dioxo‐2,3,19,20‐tetraselena‐10,12,27,29‐tetraazapentacyclo[28.4.0.04,9.013,18.021,26]tetratriaconta‐1(30),4(9),5,7,13,15,17,21,23,25,31,33‐dodecaene‐10,27‐dicarboxylate, C36H34N4O6Se4, and its precursor di‐tert‐butyl 2,2′‐[diselane‐1,2‐diylbis(2,1‐phenylene)]dicarbamate, C22H28N2O4Se2, are reported. The precusor to the macrocycle contains two tert‐butyl phenylcarbamate arms connected to a diselenide group, with Se—C and Se—Se bond lengths of 1.914 (4) and 2.3408 (6) Å, respectively. The macrocycle resides on a crystallographic center of inversion in space group P with one molecule in the unit cell (Z′ = ). It contains an 18‐membered macrocyclic ring with two diselenide linkages. In this macrocycle, there are two free and two protected amino groups.  相似文献   
50.
Using potassium iodide as a catalyst and m-chloroperbenzoic acid as an oxidant, an efficient catalytic procedure has been developed for the azidoselenenylation of alkenes with sodium azide and diselenides, and a series of corresponding β-azidoselenides, most of which are new compounds, have been prepared in moderate to good yields under mild reaction conditions. This in situ generation of the electrophilic selenenylating reagents with addition to alkenes is a stereospecific anti addition, which occurs with a Markovnikov orientation.  相似文献   
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