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21.
Torsten Ampßler Georg Monsch Jens Popp Tobias Riggenmann Pedro Salvador Daniel Schrder Peter Klüfers 《Angewandte Chemie (International ed. in English)》2020,59(30):12381-12386
Nitrosyl–metal bonding relies on the two interactions between the pair of N–O‐π* and two of the metal's d orbitals. These (back)bonds are largely covalent, which makes their allocation in the course of an oxidation‐state determination ambiguous. However, apart from M‐N‐O‐angle or net‐charge considerations, IUPAC′s “ionic approximation” is a useful tool to reliably classify nitrosyl metal complexes in an orbital‐centered approach. 相似文献
22.
Hybrid B3LYP and non-hybrid OLYP DFT formalism has been applied to neutral and reduced forms of bimetallic hydrotris(3-methylpyrazol-1-yl)borato (Tp3-Me) molybdenum nitrosyl complexes incorporating ethane-1,2-diolate bridges. Direct evidence for localization of an extra electron in mixed-valence compounds {16e:17e}− is based on the analysis of electron density, energetic stabilization of asymmetric structures with an electron trapped on one Mo and the splitting of both calculated and experimental νNO stretching frequencies. Differences in the first and second electron affinities calculated in PCM solvent model have been successfully related to cyclic voltammetry measurements. Electronic interactions through saturated ethanediolato bridges are evidenced by the extent of spin density delocalization towards the second Mo center. 相似文献
23.
24.
《Journal of Coordination Chemistry》2012,65(10):1809-1834
The rhenium(II) dinitrosyl and mononitrosyl complexes, i.e. [Re(NO)2(CN)4]·(Phen)2·2H2O (1) and PhenH[Re(NO)(CN)4(H2O)]·(Phen)·3H2O (2) have been isolated and characterized. The X-ray crystal structure of 2 reveals that Re(II) is octahedrally coordinated with one nitrosyl, four cyanides, and one water, with one phenanthroline protonated to compensate the charge of the Re(II) center. The crystal structure shows chemically significant non-covalent interactions like hydrogen bonding involving the uncoordinated water and π–π interactions between phenanthrolinium and phen. The structures of both complexes have been optimized by DFT. Absorption and emission spectral studies and viscosity measurements indicate that both 1 and 2 interact with calf thymus DNA through partial intercalation of DNA bases. The intrinsic-binding constants, obtained from UV–vis spectroscopic studies, are 1.2?×?104 and 7.2?×?104?M?1 for 1 and 2, respectively. Both 1 and 2 are capable of inducing cleavage of plasmid DNA in the presence of H2O2 to form the supercoiled form to nicked circular form. The spectroscopic results of DNA binding are supported by molecular docking studies. 相似文献
25.
26.
Going Homoleptic: Synthesis and Full Characterization of Stable Manganese Tetranitrosyl Cation Salts
Jan Bohnenberger Brandon Derstine Michael Daub Ingo Krossing 《Angewandte Chemie (International ed. in English)》2019,58(28):9586-9589
Although similar to carbon monoxide, the chemistry of homoleptic nitrogen monoxide complexes is fundamentally unexplored compared to their carbonyl analogues. Herein we report the synthesis of the first truly homoleptic transition‐metal nitrosyl cation as the salt of the weakly coordinating anions (WCAs) [Al(ORF)4]? and [F{Al(ORF)3}2]? (RF=C(CF3)3). These salts are easily accessible in good yields, phase pure, and were fully characterized by IR/Raman, NMR and UV/Vis spectroscopy as well as single‐crystal and powder X‐ray diffraction. They may serve as unprecedented simple model systems for theoretical and experimental studies of nitrosyl complexes. 相似文献
27.
FU Liang ZHAO Feng-xuan WANG Hai-yan WANG Huan-zhe CHEN Tao XU Jian-hua LI Bing XIE Hua-lin 《光谱学与光谱分析》2018,38(11):3572-3577
钌催化前驱体是影响负载型钌催化剂催化性能最重要因素。前驱体中的部分杂质会对催化性能产生抑制作用,尤其是S,P,Cl,As等杂质元素含量过高会降低催化剂的活性,严重时会造成催化剂中毒;因此,必须严格控制催化前驱体中杂质元素的含量。建立了快速准确测定催化前驱体亚硝酰硝酸钌(Ru(NO)(NO3)3)中杂质元素的分析方法。Ru(NO)(NO3)3经稀硝酸溶解后采用电感耦合等离子体串联质谱(ICP-MS/MS)直接测定其中的8个杂质元素(P,S,Ti,V,Cr,Mn,Fe,As)。为防止Ru(NO)(NO3)3溶液水解形成Ru(NO)(NO3)x(OH)3-x,采用稀硝酸介质有效维持了样品溶液的稳定性。在MS/MS模式下,通过一级四极杆质量过滤器(Q1)控制进入碰撞/反应池(CRC)的离子,仅允许与待测元素具有相同质荷比(m/z)的离子进入CRC,从而将来自样品基质和等离子气Ar所形成的干扰离子阻止在CRC外,消除了大量质谱干扰。通过向CRC内通入O2为反应气,目标离子P+,S+,Ti+,V+,As+与O2的反应为放热过程(31P++O2→31P16O++O,ΔHr=-3.17 eV;32S++O2→32S16O++O,ΔHr=-0.34 eV;48Ti++O2→48Ti16O++O,ΔHr=-1.63 eV;51V++O2→51V16O++O,ΔHr=-0.85 eV;75As++O2→75As16O++O,ΔHr=-0.63 eV),能自发反应生成氧化物离子;目标离子Cr+,Mn+与O2的反应为吸热过程(52Cr++ O2→52Cr16O++O,ΔHr=+1.38 eV;55Mn++O2→55Mn16O++O,ΔHr=+2.15 eV)。为促进Cr+,Mn+与O2发生反应,通过调整CRC的工作参数,设置八极杆偏置电压为较大的负电压,使Cr+和Mn+在与O2反应前被加速,提高Cr+和Mn+的动能,促进了反应的发生,通过吸热反应生成氧化物离子;而P+,S+,Ti+,V+,Cr+,Mn+,As+干扰离子在CRC内不能与O2发生反应,仍然保持原始的m/z。通过二级四极杆质量过滤器(Q2)将这些干扰离子阻止在外,仅允许所形成的氧化物离子进入检测器,几乎完全消除了元素P,S,Ti,V,Cr,Mn,As的所有质谱干扰。NH3因含一对孤对电子而具有高反应活性,能与很多金属离子反应形成团簇离子。通过向CRC内通入NH3/He为反应气,目标离子Fe+与NH3发生质量转移反应,在所形成多个团簇离子中,Fe(NH3)+2的丰度最高且无干扰,通过NH3质量转移法消除干扰。结果显示,8个元素在0~500 μg·L-1范围内具有良好的线性关系,线性相关系数≥0.999 8。方法的检出限为0.29~485 ng·L-1,按所建立的方法分析了实际样品中8个杂质元素的含量,各元素的加标回收率为93.2%~107.5%,相对标准偏差(RSD)≤3.9%。方法具有样品处理简单、分析速度快和精密度高的特点,适合催化前驱体亚硝酰硝酸钌中多个杂质元素的准确测定,为制备负载型钌催化剂提供了质量保障。 相似文献
28.
Shirokii V. L. Knizhnikov V. A. Sutormin A. B. Maier N. A. Andrianov Yu. A. Sedova L. G. 《Russian Chemical Bulletin》1994,43(6):1061-1062
The dependence of the yield of -cyclopentadienyl(nitrosyl)nickel on the conditions of its electrochemical synthesis from cyclopentadiene under an atmosphere of nitric oxide has been studied with the use of a nickel anode. The general character of the reaction has been demonstrated by its extention to monosubstituted ethyl-, isopropyl-, and benzoylcyclopentadienes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1123–1124, June, 1994. 相似文献
29.
Soo-Gyun Roh Anna Proust Francis Robert Pierre Gouzerh 《Journal of Cluster Science》1996,7(4):593-627
The reactions of 2-thienylamidoxime and 2-thienylmethylamidoxime with [MoO2(acae)2] or x-(NBu4 [Mo8O26]. in alcohols or acetonitrile, yield a number of compounds with different nuclearities and various molybdenum cores, such as the compact {Mo4O10(OMe)2}2+ the cyclic {Mo4O12}, and the open {Mo11On211-1}2+ (n= 2 or 4) cores. Addition of NH2OH to the reaction mixtures results in the formation of nitrosyl complexes containing either the Mo(NO)3 or the Mo(NO)
2
2
units. The amidoxime component may be present either as RC(NH2)NHO. RC(NHi2), RC(NH)NHO or RC(NH)NO2: ligands, or as hydrogen-bonded RC(NH2)NOH molecules. The crystal structures of [MoO(acac)RIC'(NH2)NO] {RJC(NH)NO}](1), [Mo(NO)(acae)2 {RIC(NH2)NO}] (4), (NBu4)2[Mo4O10(OMe)2{RIC(NH) NO}2] (12a),(NBu4)2(H3O)[Mo5O13(OMe)4(NO)].2R1C(NH2)NOH(13b) and [R1C(NH2)2)]3[Mo5O13(OEt)4(NO)] (14) (R1=2-thienyl) are reported. The cryslallographic data for these compounds are as follows:1, mono-clinic. P21 a.a=24.547(4)A. b=8.188(4)A. c=9.607(3)A, ß=96.18(3)c, R=0.046. R10=0.050: 4. monoclinic, P21c.a=8.265(2)A, b=9.381(2)A,c=24.770(4)A, c = 24.7701(4) A, ß=93.99(2). R=0.039. R=0.042;12a, monoclinic, C2/c, a= 19.570(5)A. b=16.883(4)A, c = 19.82(l)A. ß= 114.36(5)°, R=0.064,R.=0.074;13b monoclinic;. P21 c.a=18.197(5)A, b=15.857(14) A, c = 23.075(17) A, =93.20(3). R=O.050. Rw=0.057;14, trictinic PI, a = 9.871(3),b= 14.138(3).c= 14.781(8)A. =92.67(2)c =99.36(1)° =90.52(2)°. R = 0.044. Rw = 0.049. Particular attention is focused on the various coordination modes that the different ligand forms adopt: µ- O, 2N,O, 2N',O, µ-N: 2O. and 3- N:N:2O. 相似文献
30.
On the basis of density functional theory (DFT), the iron–nitrosyl complex Fe[Me3TACN](NO)(N3)2 (S = 3/2) is studied via the B3LYP hybrid method. Its Raman vibrational frequencies, atomic net charges, and spin densities are analyzed. The related complexes Fe(NH3) (n = 1, 2, and 3) are employed as reference compounds to determine the characteristics of the central iron. Our results indicate that the S = 3/2 spin ground state of Fe[Me3TACN](NO)(N3)2 is best described by the presence of FeII (S = 2) anti‐ferromagnetically coupled to NO0 (S = 1/2) yielding FeII[Me3TACN](NO0)(N)2. This is clearly different from the previous FeIII‐NO? theoretical assignment. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献