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51.
Dr. Robin Guthardt Lisa Oetzel Tobias Lang Dr. Clemens Bruhn Prof. Dr. Ulrich Siemeling 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(42):e202200996
The reactivity of ferrocene-based N-heterocyclic tetrylenes [{Fe(η5−C5H4−NSitBuMe2)2}E] (E=Ge, Sn, Pb) towards mesityl azide (MesN3) is compared with that of PPh2-functionalised congeners exhibiting two possible reaction sites, namely the EII and PIII atom. For E=Ge and Sn the reaction occurs at the EII atom, leading to the formation of N2 and an EIV=NMes unit. The germanimines are sufficiently stable for isolation. The stannanimines furnish follow-up products, either by [2+3] cycloaddition with MesN3 or, in the PPh2-substituted case, by NMes transfer from the SnIV to the PIII atom. Whereas [{Fe(η5−C5H4−NSitBuMe2)2}Pb] and other diaminoplumbylenes studied are inert even under forcing conditions, the PPh2-substituted congener forms an addition product with MesN3, thus showing a behaviour similar to that of frustrated Lewis pairs. The germylenes of this study afford copper(I) complexes with CuCl, including the first structurally characterised linear dicoordinate halogenido complex [CuX(L)] with a heavier tetrylene ligand L. 相似文献
52.
Raoul R. Nigmatulin Alexander P. Alekhin Dumitru Baleanu Erdal Dinç Zafer Üstündağ Haslet Ekşi Ali Osman Solak 《Electroanalysis》2010,22(4):419-426
The effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms was studied for the statistical characterization of nitrobenzene (NB) and nitroazobenzene (NAB)‐modified glassy carbon (GC) surfaces. Both NB and NAB nanofilms were obtained by the electrochemical reduction of the diazonium tetrafluoroborate salts in acetonitrile using cyclic voltammetry (CV). The modified surfaces were denoted as GC‐(NB)n and GC‐(NAB)n, respectively, where n indicates the number of CV cycles performed during modification. Reflective IR signals of the normalized NB and NAB nanofilms and GC were used for the quantitative evaluation of the effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms. The detection and quantitative ‘reading’ of the influence of number of CV cycles were realized in the frame of a new error controllable approach that was applied for analysis of all available set of data. This approach includes in itself the following basic steps: (a) the procedure of the division (normalization) on the GC spectra, (b) the comparison of the smoothed spectra for their statistical proximity in the frame of the statistics of the fractional moments, (c) extraction of possible calibration parameters for possible calibration of the normalized spectra with respect to the number of CV cycles. These three basic steps are becoming effective for detection of the influence of some external factors. In our case it is important to detect the influence of the factor n characterizing CV cycles. 相似文献
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54.
Arménio C. Serra 《Tetrahedron letters》2010,51(32):4192-4194
Chlorins have been synthesized through the reduction of the corresponding porphyrins although theoretically they can be obtained from reduced macrocycle forms as porphyrinogens. A new method for the oxidation of meso-tetraarylporphyrinogens was developed generating a substantial amount of chlorin relatively to porphyrin. The structure of the porphyrinogen, particularly the presence of substituents on the meso-phenyl groups, is decisive for the final yield of chlorin. In the case of meso-tetrakis(2,6-dichlorophenyl)porphyrinogen, 92% of the corresponding chlorin is obtained. 相似文献
55.
在气相色谱法测定溶剂型木器涂料中正丁醇及苯系物(包括苯、甲苯及二甲苯)时采用了VF-200MS型号的毛细管色谱柱。由于此型号的毛细管柱具有较强极性,不仅能达到正丁醇与苯系物之间的有效而满意的分离,而且还能使苯系物(包括苯、甲苯、乙苯、二甲苯)之间和二甲苯的同分异构体之间的有效分离。测定中采用正戊烷作内标和用火焰离子检测器检测。此方法的检出限(2S/N)在1.7~3.5 ng之间。用一含有正丁醇的硝基漆样品按所提出的方法进行多次重复测定,并在此样品的基础上加入各被测化合物的标准后进行测定,从而对方法的回收率和精密度作了测试,测得其回收率在87.8%~100.0%之间,测定值的相对标准偏差(n=6)均小于2.5%。 相似文献
56.
顶空-气相色谱法测定水中苯系物、乙腈和丙烯腈 总被引:1,自引:0,他引:1
梁坚 《理化检验(化学分册)》2010,(4)
运用顶空-气相色谱法同时测定水中苯系物、乙腈和丙烯腈,使用DB-WAX色谱柱实现了各组分的良好分离。用外标法以峰面积定量,苯系物各组分的质量浓度在0.01~0.10 mg·L~(-1),乙腈的质量浓度在0.20~2.00 mg·L~(-1),丙烯腈的质量浓度在0.10~1.00 mg·L~(-1)范围内呈线性关系。方法的检出限(3S/N)为0.7~19.8μg·L~(-1)。在空白水样的基础上用标准加入法对方法作回收及精密度试验,测得各被测物质的回收率在97.3%~104.8%之间,测定结果的相对标准偏差(n=6)为2.17%~4.24%。 相似文献
57.
58.
贮氢合金用作硝基苯电解加氢的催化电极研究 总被引:15,自引:1,他引:15
贮氢合金用作硝基苯电解加氢的催化电极研究卢世刚,杨汉西,王长发(武汉大学化学系,武汉130072)混合稀土贮氢合金是近年来发展起来的新型功能材料。在室温下它可以吸收比自身体积大几百倍的氢原子形成金属氢化物.这种金属氢化物可作为氢源提供高反应活性的氢原... 相似文献
59.
HYDROGENATION OF NITROBENZENE TO FORM ANILINE IN LIQUID PHASE AT ATMOSPHERIC PRESSURE* 总被引:1,自引:0,他引:1
YIN Jingbo YANG Yana Zhubanov K. A Bizhanowa N. B Jilin Institute of Technology Changchun China Kazakstan National University Alma-Ata Kazakstan 《Chinese Journal of Reactive Polymers》2001,(1)
1. EXPERIMENT SECTION1.1 Reagent and InstrumentNitrobenzene (chemical purity), alcohol (medical), hydrogen (electrolytic method 99.8%), anion exchange resin AH-1 PdCl2, 2H20 (Pd containing 59%), NaCl, LXM-80-type vapor-liquid chromatograph (made in Russia), ZD-2-type potentiometer (made in Russia). 1.2 Catalyst PreparationThere are two methods of catalyst preparation, one of which is adsorption: putting PdCl2?2H2O, AH-1, NaCl and distilled water in oscillating hydrogenation re… 相似文献
60.