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101.
M. Sc. Fabian Spitzer Prof. Dr. Marek Sierka Prof. Mario Latronico Prof. Dr. Piero Mastrorilli Dr. Alexander V. Virovets Prof. Dr. Manfred Scheer 《Angewandte Chemie (International ed. in English)》2015,54(14):4392-4396
By the reaction of [NacnacCuCH3CN] with white phosphorus (P4) and yellow arsenic (As4), the stabilization and enclosure of the intact E4 tetrahedra are realized and the disubstituted complexes [(NacnacCu)2(μ,η2:2‐E4)] ( 1 a : E=P, 1 b : E=As) are formed. The mono‐substituted complex [NacnacCu(η2‐P4)] ( 2 ), was detected by the exchange reaction of 1 a with P4 and was only isolated using low‐temperature work‐up. All products were comprehensively spectroscopically and crystallographically characterized. The bonding situation in the products as intact E4 units (E=P, As) was confirmed by theory and was experimentally proven by the pyridine promoted release of the bridging E4 tetrahedra in 1 . 相似文献
102.
Christian Marquardt Oliver Hegen Matthias Hautmann Dr. Gábor Balázs Dr. Michael Bodensteiner Dr. Alexander V. Virovets Prof. Dr. Alexey Y. Timoshkin Prof. Dr. Manfred Scheer 《Angewandte Chemie (International ed. in English)》2015,54(44):13122-13125
The synthesis of the Lewis base stabilized monomeric parent compound of stibanylboranes, “H2Sb? BH2”, is reported. Through a salt metathesis route, the silyl‐substituted compounds (Me3Si)2Sb? BH2?LB (LB=NMe3, NHCMe) were synthesized as representatives of derivatives with a Sb? B σ bond. Under very mild conditions, they could be transformed into the target compounds Me3N?H2B? HSb? BH2?NMe3 and H2Sb? BH2?NHCMe, respectively. The products were characterized by X‐ray structure analysis, NMR spectroscopy, IR spectroscopy, and mass spectrometry. DFT calculations give further insight into the stability and bonding of these unique compounds. 相似文献
103.
L. B. Serezhkina E. V. Peresypkina A. V. Virovets E. V. Grechishnikova A. V. Savchenkov 《Russian Journal of Inorganic Chemistry》2011,56(11):1739-1746
The complex [UO2(SeO4)(C5H12N2O)2(H2O)] (I) was synthesized and studied by thermal analysis, IR spectroscopy, and X-ray crystallography. The crystals are orthorhombic: a = 13.1661(3) Å, b = 16.4420(5) Å, c = 17.4548(6) Å, Pbca, Z = 8, R = 0.0423. The structural units of crystal I are chains with the composition coinciding with that of the compounds of the AB2M 3 1 crystal chemical group of the uranyl complexes (A = UO 2 2+ , B2 = SeO 4 2? , M1 = C5H12N2O and H2O). 相似文献
104.
Dielmann F Schindler A Scheuermayer S Bai J Merkle R Zabel M Virovets AV Peresypkina EV Brunklaus G Eckert H Scheer M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(4):1168-1179
Slow diffusion reactions of the pentaphosphaferrocene [Cp*Fe(η(5)-P(5))] (Cp*=η(5)-C(5)Me(5) (1)) with CuX (X=Cl, Br, I) in different stoichiometric ratios and solvent mixtures result in the formation of one- and two-dimensional polymeric compounds 2-6 with molecular formula [{Cu(μ-X)}{Cp*Fe(μ(3),η(5):η(1):η(1)-P(5))}](n) (X=Cl (2a), I (2'c)), [{Cu(μ-I)}{Cp*Fe(μ(3),η(5):η(1):η(1)-P(5))}](n) (3), [{CuX}{Cp*Fe(μ(4),η(5):η(1):η(1):η(1)-P(5))}](n) (X=Cl (4a), Br (4b), I (4c), Br (4'b), I (4'c)), [{Cu(3)(μ-I)(2)(μ(3)-I)}{Cp*Fe(μ(5),η(5):η(1):η(1):η(1):η(1)-P(5))}](n) (5) and [{Cu(4)(μ-X)(4)(CH(3)CN)}{Cp*Fe(μ(7),η(5):η(2):η(1):η(1):η(1):η(1):η(1)-P(5))}](n) (X=Cl (6a), Br (6b)), respectively. The polymeric compounds have been characterised by single-crystal X-ray diffraction analyses and, for selected examples, by magic angle spinning (MAS) NMR spectroscopy. The solid-state structures demonstrate the versatile coordination modes of the cyclo-P(5) ligand of 1, extending from two to five coordinating phosphorus atoms in either σ or σ-and-π fashion. In compounds 2a, 2'c and 3, two phosphorus atoms of 1 coordinate to copper atoms in a 1,2 coordination mode (2a, 2'c) and an unprecedented 1,3 coordination mode (3) to form one-dimensional polymers. Compounds 4a-c, 4'b, 4'c and 5 represent two-dimensional coordination polymers. In compounds 4, three phosphorus atoms coordinate to copper atoms in a 1,2,4 coordination mode, whereas in 5 the cyclo-P(5) ligand binds in an unprecedented 1,2,3,4 coordination mode. The crystal structures of 6a,b display a tilted tube, in which all P atoms of the cyclo-P(5) ligand are coordinated to copper atoms in σ- and π-bonding modes. 相似文献
105.
S. B. Artemkina M. S. Tarasenko A. V. Virovets N. G. Naumov 《Russian Journal of Coordination Chemistry》2012,38(4):257-263
Heterometallic chloride complexes [Mo5NbI8Cl6]
n− (n = 2, 3) are synthesized. The crystal structures of their salts are determined: for (Ph4P)2[Mo5NbI8Cl6] (I), triclinic crystal system, spacegroup P
[`1]\bar 1, a = 10.9886(6), b = 11.4604(5), c = 13.4343(7) ?, α = 66.124(2), β = 86.892(2), γ = 86.490(2)°, Z = 1, V = 1543.35(13) ?3; and for (4-MePyH)5[Mo5NbI8Cl6]Cl2 (II), monoclinic crystal system, space group C2/m, a = 16.4937(4), b = 14.7335(3), c = 11.6534(3) ?, β = 99.8750(10)°, Z = 2, V = 2789.94(11) ? The geometric parameters of compounds I and II and the conditions for the formation of the complexes with the charges −2 and −3 are discussed. 相似文献
106.
L. G. Lavrenova A. D. Strekalova A. V. Virovets D. A. Piryazev V. A. Daletskii L. A. Sheludyakova T. F. Mikhailovskaya S. F. Vasilevskii 《Russian Journal of Coordination Chemistry》2012,38(8):507-514
Iron(II) complexes with tris(3,5-dimethylpyrazol-1-yl)methane {HC(3,5-Me2Pz)3} of the composition [Fe{HC(3,5-Me2Pz)3}2]Am · nH2O (A = Cl? (I), ClO 4 ? (II), SO 4 2? (III), CF3SO 3 ? (IV), m = 1, 2, n = 0.1) are synthesized. The compounds are studied by static magnetic susceptibility, IR and diffuse reflectance spectroscopy, and X-ray structure analysis. The crystal structures of two polymorphous modifications of the [Fe{HC(3,5-Me2Pz)3}2](ClO4)2 (IIa and IIb) and [Fe{HC(3,5-Me2Pz)3}2](CF3SO3)2 (IV) complexes are determined. The temperature dependence ??eff(T) shows that the spin crossover 1 A 1 ai 5 T 2 is observed in the polycrystalline phase of complex I and in one of the single-crystal phases of complex II (IIa) and is accompanied by thermochromism (the change of the dark pink color ai to white). 相似文献
107.
Yu. R. Giniyatullina E. V. Peresypkina A. V. Virovets T. G. Cherkasova E. S. Tatarinova 《Russian Journal of Inorganic Chemistry》2012,57(6):811-814
A new complex [{Cd(?-Cpl)5}2Cr(NCS)6][Cd(?-Cpl)4Cr(NCS)6] was synthesized, and its crystal structure was solved. The complex was studied by chemical analysis and IR spectroscopy. 相似文献
108.
P. A. Abramov M. N. Sokolov A. V. Virovets V. P. Fedin 《Journal of Structural Chemistry》2009,50(1):162-165
The crystal structure of [(C5Me4Et)3Rh3(μ3-Se)2](PF6)2 and [(C5Me4Et)2Rh2(μ2-Cl)3]PF6, obtained in the reaction of [(C5Me4Et)Rh(C6H6)](PF6)2 with ZnSe in 4M HCl under hydrothermal conditions, is determined. In agreement with the 18VE rule, the triangular cluster
contains single metal-metal bonds (Rh-Rh 2.864(1) ?), whereas they are absent in the binuclear complex (Rh ...Rh 3,216(1)
?).
Original Russian Text Copyright ? 2009 by P. A. Abramov, M. N. Sokolov, A. V. Virovets, and V. P. Fedin
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 169–172, January–February, 2009. 相似文献
109.
L. B. Serezhkina E. V. Peresypkina A. V. Virovets I. V. Medrish D. V. Pushkin 《Russian Journal of Inorganic Chemistry》2009,54(10):1577-1580
Single crystals of Cs[(UO2)2(C2O4)2(OH)] · H2O were synthesized and structurally studied using X-ray diffraction. The compound crystallizes in monoclinic space group P21/m, Z = 2, with the unit cell parameters a = 5.5032(4) Å, b = 13.5577(8) Å, c = 9.5859(8) Å, β = 97.012(3)°, V = 709.86(9) Å3, R = 0.0444. The main building units of crystals are [(UO2)2(C2O4)2(OH)]? layers of the A2K 2 02 M2 (A = UO 2 2+ , K02 = C2O 4 2? , and M2 = OH?) crystal-chemical family. Uranium-containing layers are linked into a three-dimensional framework via electrostatic interactions with outer-sphere cations and hydrogen bonds with water molecules. 相似文献
110.
Pavel A. Shelyganov Alexander Virovets Eugenia Peresypkina Manfred Scheer Alexey Y. Timoshkin 《无机化学与普通化学杂志》2019,645(3):317-322
The molecular structure of the complex of ammonia borane (AB) with acyclic ether tetraglyme Me(OCH2CH2)4OMe ( 1 ), 1· (AB)2 was determined by single‐crystal X‐ray structure analysis for the first time. The crystal structure features two AB molecules, bonded by dihydrogen bonds, per one tetraglyme unit. The intermolecular BH ··· HN distances of 1.94 Å are shorter than those in the solid ammonia borane (2.02–2.32 Å). A comparison of the hydrogen and dihydrogen bonds in 1· (AB)2 and in the complexes of AB with crown‐ethers (CE) was carried out. The complex formation with both the CE and the acyclic polyether 1 activates the B–H bond in AB via N–H ··· O hydrogen bonds and therefore increases the reducing activity of AB. Supposedly, the structure of 1· (AB)2 is related to the initial steps of the AB activation in a polyether solution. The effect of the substituents on the complexation of the substituted derivatives of 1 comes down to a structural adjustment minimizing steric repulsion. Computations reveal that the complexation of diastereomeric disubstituted glymes with AB leads to the formation of diastereomeric complexes that differ noticeably in stability. This is a prerequisite for inducing stereoselectivity, which makes such complexes attractive for potential synthetic applications. 相似文献