Structural study of complex [Rh(NH3)5(NO2)](NO3)2·H2O, [Rh(NH3)5(NO2)][Pd(NO2)4], and K2[Rh(NH3)(NO2)5]·H2O salts

Compounds [Rh(NH₃)₅(NO₂)](NO₃)₂·H₂O (I) with a = 7.6230(3) Å, b = 7.6230(3) Å, c = 10.3584(4) Å, space group I-42m, Z = 2, d _calc = 2.026 g/cm³, V = 601.93(4) ų, Rh-NH_{3 eq} = 2.074 Å, Rh-NH_{3 ax} (NO₂) = 2.048 Å; [Rh(NH₃)₅(NO₂)][Pd(NO₂)₄] (II) with a = 8.095(3) Å, b = 22.422(8) Å, c = 7.887(3) Å, β = 98.559(17)°, space group Cc, Z = 4, d _calc = 2.461 g/cm³, V = 1415.6(9) ų, Rh-NH_{3 eq} = 2.069 Å, Rh-NH_{3 ax} = 2.090 Å, Rh-NO₂ = 2.002 Å; K₂[Rh(NH₃)(NO₂)₅]·H₂O (III) with a = 7.5177(5) Å, b = 20.9856(15) Å, c = 7.7017(5) Å, space group Cmc2₁, Z = 4, d _calc = 2.439 g/cm³, V = 1215.05(14) ų, Rh-NH_{3 ax} (NO₂) = 2.094 Å, Rh-NO_{2 eq} = 2.030 Å are synthesized and studied using single crystal X-ray diffraction.     

Crystal structure and properties of [M(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl](NO<Subscript>3</Subscript>)<Subscript>2</Subscript>, (M = Ir,Rh, Ru)

The crystal structures of compounds from the series [M(NH₃)₅Cl](NO₃)₂, (M = Ir, Rh, Ru) were described. The compounds crystallized in the tetragonal crystal system, space group I4, Z = 2. Crystal data for [Ir(NH₃)₅Cl](NO₃)₂ (I): a = 7.6061(1) Å, b = 7.6061(1) Å, c = 10.4039(2) Å, V = 601.894(16) ų, ρ_calc = 2.410 g/cm³, R = 0.0087; [Rh(NH₃)₅Cl](NO₃)₂ (II): a = 7.5858(5) Å, b = 7.5858(5) Å, c = 10.41357(7) Å, V = 599.24(7) ų, ρ_calc = 1.926 g/cm³, R = 0.0255; [Ru(NH₃)₅Cl](NO₃)₂ (III): a = 7.5811(6) Å, b = 7.5811(6) Å, c = 10.5352(14) Å, V = 605.49(11) ų, ρ_calc = 1.896 g/cm³, R = 0.0266. The compounds were defined by IR spectroscopy and XRPA and thermal analyses.     

Synthesis and crystal structure of [Cr(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl][PdBr<Subscript>4</Subscript>]

A new binary complex salt — chloropentaamminechromium(III) tetrabromopalladate(II) [Cr(NH₃)₅Cl][PdBr₄] — has been synthesized. The compound was characterized by elemental, X-ray diffraction, and X-ray phase analysis. The salt is isostructural with the previously investigated compounds [M(NH₃)₅Cl][PtCl₄] (M = Ir, Rh, Ru, Co, Cr) and [CM(NH₃)₅Cl][PdBr₄] (M = Ir, Rh, Co). Crystallographic data: space group Pnma, a = 17.068(2) Å, b = 8.315(12) Å, c = 9.653(14) Å; V = 1370.0(3) ų, Z = 4, d _calc = 2.903 g/cm³.     

Neutronenpulverdiffraktionsmessungen an [Zn(ND3)4]I2 bei 1,5 K, 10 K und 293 K: Wasserstoff-Brückenbindungen und Bewegungen von ND3-Molekülen

Neutron Powder Diffraction Measurements on [Zn(ND₃)₄]I₂ at 1.5 K, 10 K, and 293 K: Hydrogen Bonds and Dynamic of ND₃ Molecules Microcrystalline powder of [Zn(ND₃)₄]I₂ can be prepared by the reaction of gaseous NH₃ with dry ZnI₂ at room temperature within 8 h. Neutron powder diffraction measurements at 1.5 K, 10 K and 293 K were used to localize all hydrogen atoms. Isolated [Zn(ND₃)₄]²⁺ tetrahedra are three dimensionally linked with 2- and 3-centre (bent and bifurcated) N? D …? I^?-hydrogen bonds. Ammonia molecules are ordered at 1.5 K. Room temperature high thermal displacement parameters for D hint to the fact that NH₃-dynamics take place. Lattice parameters 300 K [10 K; 1,5 K]: a = 10.3783(8) Å [10.3407(4) Å; 10.3381(5)], b = 7.5239(6) Å [7.3960(2) Å; 7.3935(4) Å], c = 13.088(1) Å [12.9731(4) Å; 12.9695(6) Å], space group: Pnma.     

Crystal structure of [Co(NH3)5NO2]C2O4. Analysis of specific contacts and structural effects hindering inner-spheric nitro-nitrito isomerization

The structure of [Co(NH₃)₅NO₂]C₂O₄ is solved and refined (space group Immm, a=7.428(2), b=9.790(3), c=6.568(1) Å, V=477.6(2) ų, Z=2; R₁=0.0177, wR₂=0.0279 for F²>4σ(F²); R₁=0.1177, wR₂=0.0643 for all data; residual electron density from 0.125 to ?0.140 e/ų). Specific contacts in the structure are analyzed. Crystal chemical interpretation is suggested to explain the occurrence of photodecomposition rather than photochemical bond isomerization under the action of light in cobalt(III) nitropentammoniate oxalate crystals, in contrast to all previously investigated cobalt(III) nitropentammoniates.     

Comparative study of crystal structures of [M(NH3)5NO2]XY and [M(NH3)5ONO]XY. Crystal structure of [Co(NH3)5NO2](NO3)2·0.25H2O

The crystal structure of [Co(NH₃)₅NO₂](NO₃)₂·0.25H₂O has been determined. Co₁N₈O_8.25H_15.5, a=7.582(3), c=10.331(3) Å, V=593.9(5) ų, d_calc=1.782 g/cm³ for Z=2, space group I 4mm (C _4v ⁹ , No. 107). The structure is of the island type. Complex (distorted octahedral) cations are bonded to the NO ₃ ^? anions by electrostatic forces. Crystallization water is located in the vicinity of the labile NO₂ group.     

STEREOCHEMISTRY OF (R)-2-METHYLAZIRIDINE COMPLEXES OF COBALT(III) AND DIMERIZATION OF THE LIGAND

Abstract

A cobalt(III) complex containing (R)-2-methylaziridine (R-meaz), [Co(R-meaz)(NH₃)₅]³⁺, was prepared and the two diastereomers arising from the presence of the chiral nitrogen atom (N(R) and N(S)) were separated by column chromatography. Molecular mechanics calculations estimated the N(R)-isomer to be more stable. This result was supported by the x-ray structure determination of the more abundant (ca. 94%) isomer, N(R)-[Co(R-meaz)(NH₃)₅]Br₃H₂O. Crystal data: monoclinic, P2₁, a = 7.357(1), b = 9.780(1), c = 10.426(1) Å, μ = 93.58(1)°, V= 748.7(3) ų, Z= 2. Kinetic studies of isomerization (epimerization) between the two isomers revealed that inversion at the nitrogen center was very slow (5 × 10^?2 M^?1 S^?1at 25 °C). The small rate constant seems to be related to the strained three-membered structure of the meaz ligand. The reaction of Na₃[Co(N0₂)6] and R-meaz yielded a complex containing two dimerized R-meaz chelates, trans-[Co(NO₂)2(di-R-meaz)₂] (di-R-meaz =RR)-α,2-dimethyl-l-aziridineethanamine). The crystal strucrure of trans-[Co(NO₂)₂ (di-R-meaz)₂]C1O₄H₂O was established by x-ray crystallography. Crystal data: orthorhombic, P2₁2₁2₁, a = 11.784(6), b = 21.023(9), c = 8.608(7) Å, V = 2133(2) ų, Z = 4.     

Synthesis and crystal structures of lithium and potassium hexanitroruthenates (II)

A procedure for preparing Li₄[Ru(NO₂)₆]…12H₂O and K₄[Ru(NO₂)₆] is described. We have carried out an X-ray diffraction study of polycrystals (DRON-UM1 diffractometer, R=192mm, CuK_α radiation, Ni filter) and single crystals (CAD-4 automatic diffractometer, MoK_α radiation, graphite monochromator, ω/2? scan mode). Crystal data for Li₄[Ru(NO₂)₆]…12H₂O are a=11.749(9), c=16.807(12) Å, space group $I\bar 4$ , V=2320.0 ų, Z=4, d_calc=1.778 g/cm³; for K₄ [Ru(NO₂)₆]: a=8.595(1) Å, α=53.23 (2)^o, space group $R\bar 3$ , V=367.0 ų, Z=1, d_calc=2.414 g/cm³. The structures are composed of [Ru(NO₂)₆]^4? comple anions, alkaline metal cations, and crystallization water molecules. In both compounds, the coordination polyhedra of Ru are nearly regular octahedra formed by nitrite nitrogen atoms. The Ru-N bond lengths are 2.054–2.102 Å. The NO₂ groups have virtually the same geometric characteristics: the N?O distances are within 1.196–1.316 Å and the O?N?O angles are 112.9–117.4^o. The coordination environment of alkaline metals by oxygen atoms is discussed.     

Crystal structure refinement for trans-[Pd(NO3)2(H2O)2]

Single crystals of trans-[Pd(NO₃)₂(H₂O)₂] were obtained, and the crystal structure of this complex, previously obtained for polycrystals, was refined. Crystal data (BRUKER X8APEX diffractometer): a = 4.9973(7) Å, b = 10.5982(14) Å, c = 11.7008(17) Å, V = 619.70(15) ų, space group Pbca, Z = 4, d _calc = 2.856 g/cm³. The structure is composed of neutral complexes with a trans configuration. The square plane environment of the Pd atom is formed by four oxygen atoms (Pd-O(NO₃) 1.999(5) Å, Pd-O(H₂O) 2.030(5) Å) and completed to a distorted bipyramid by two intramolecular contacts (Pd…O(NO₃) 2.926 Å). The shortest hydrogen bonds are O…H 2.72 Å.     

Anhydrous Nitrates and Nitrosonium Nitratometallates of Manganese and Cobalt,M(NO3)2, NO[Mn(NO3)3], and (NO)2[Co(NO3)4]: Synthesis and Crystal Structure

Crystalline NO[Mn(NO₃)₃] ( I ) and (NO)₂[Co(NO₃)₄] ( II ) were synthesized by reaction of the corresponding metal and a liquid N₂O₄/ethylacetate mixture. I is orthorhombic, Pca2₁, a = 9.414(2), b = 15.929(3), c = 10.180(2) Å, Z = 4, R₁ = 0.0286. II is monoclinic, C2/c, a = 14.463(3), b = 19.154(4), c = 13.724(3) Å, β = 120.90(3), Z = 12, R₁ = 0.0890. Structure I consists of [Mn(NO₃)₃]^– sheets with NO⁺ cations between them. Two types of Mn atoms have CN_Mn = 7 and 8. Structure II is ionic containing isolated [Co(NO₃)₄]‐anions and NO⁺ cations with CN_Co = 8. Crystals of Mn(NO₃)₂ ( III ) and Co(NO₃)₂ ( IV ) were obtained by concentration of metal nitrate hydrate solutions in 100% HNO₃ in a desiccator with P₂O₅. III is cubic, Pa 3, a = 7.527(2) Å, Z = 4, R₁ = 0.0987. IV is trigonal, R 3, a = 10.500(2), c = 12.837(3) Å, Z = 12, R₁ = 0.0354. The three dimensional structure III is isotypic to the strontium and barium dinitrates. Structure IV contains a three dimensional network of interconnected Co(NO₃)_6/3 units with a distorted octahedral coordination environment of Co atoms. General correlations between central atom coordination and coordination modes of NO₃ groups are discussed.     

Die Molekül- und Kristallstruktur von [Co3(CN)2 {(OH)4} (NH3)8][Co2(NO2)6 {(OH)2, NO2}] · H2O

The structure of [Co₃(CN)₂ {(OH)₄} (NH₃)₈] [Co₂(NO₂)₆ {(OH)₂, NO₂}] · H₂O has been determined by X-ray methods. The compound crystallizes in the monoclinic space group C_2h⁵–P2₁/n with a = 7.21, b = 12.38, c = 33.13 Å, β = 94°, Z = 4. The crystals contain trinuclear cations in which three Co(III) atoms are bound to two pairs of oxygen atoms. At the central Co atom there are two CN^– ligands in the cis position. The cation is of symmetry C₂. The anion is found to be a binuclear Co(III) complex. The two Co atoms are bound to two OH^– and one NO₂^– groups.     

Synthesis and structure of complex compound Rh(III) of (NH4)2[Rh(NO2)3(NH3)(µ-OH)]2 composition

The crystalline structure of a new compound Rh(III) of (NH₄)₂[Rh(NO₂)₃(NH₃)(μ-OH)]₂ composition has been determined. The crystallographic characteristics are H₁₆N₁₀O₁₄Rh₂: a = 6.3963(2) Å, b = 9.3701(4) Å, c = 13.6646(5) Å, β = 102.266(1)°, V = 800.28(5) ų, Z = 2, d _calc = 2.432 g/cm³. The distance Rh...Rh in the dimer is 3.200 Å. Original Russian Text Copyright ? 2006 by S. P. Khranenko, I. A. Baidina, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No. 2, pp. 380–384, March–April, 2006.     

Mehrkernige Kobaltkomplexe. II. Herstellung und Struktur von [(tren) (NH3)Co(O2)Co(NH3) (tren)](SCN)4 · 2H2O

Polynuclear Cobalt Complexes. II. Preparation and Structure of [(tren) (NH₃)Co(O₂)Co(NH₃) (tren)](SCN)₄ · 2H₂O The title compound is obtained on oxygenation of [Co(tren)(H₂O)₂]²⁺ in 6M aqueous ammonia or by ligand exchange starting from [(NH₃)₅Co(O₂)Co(NH₃)₅]-(NO₃)₄. An X-ray structure determination was made. The substance forms monoclinic crystals, space group P2₁/c, lattice constants a=10,135, b=8,473, c=19,484 Å, β=108,58°, with two formula units in the cell. The final R is 0,066. The binuclear cation has a center of symmetry, so the Co? O? O? Co unit is planar; the Co? O? O angle is 111,5°. The tertiary nitrogen atoms of both chelate groups are cis to the O₂ bridge, as found in doubly bridged [(tren)Co(O₂,OH)Co(tren)](ClO₄)₃ · 3H₂O. On acidification in solution, the singly bridged cation [(tren) (NH₃)CoO₂Co(NH₃)(tren)]⁴⁺ (a) loses the bound O₂ completely. But unlike the doubly bridged cation b , the rate of dissociation of a is independent of pH (Fig. 5). At higher pH (8–10) bridging a→b (Fig. 2) occurs. Both reactions must have the same rate determining step, the first order rate constants being of the order of 2 · 10^?3 s^?1 (25°, 0,35M KCl).     

Cobalt-Komplexe mit O2-Brücken: Die Struktur von μ-Peroxo-bis[pentaammincobalt(III)]-tetranitrat-dihydrat

Cobalt Complexes with 0₂ Bridges: Structure of μ-Peroxo-bis[pentaamminecobalt(III)] Tetranitrate Dihydrate An X-ray structure determination of the binuclear complex [(NH₃)₅CoO₂Co(NH₃)₅] (NO₃)₄ · 2 H₂O A has been performed; R = 0.051. A crystallizes in the space group P2₁/n with Z = 2 and with lattice constants a = 11.657(5), b = 11.977(6), c = 8.082(4) Å, and β = 91.58(4)°. The complex cation has crystallographic 1 -symmetry. The Co? O? O? Co unit is planar with an O? O distance of 1.472(6) Å. Two of the three crystallographically independent NO₃ groups show disorder.     

Synthesis and structure of trinuclear clusters (Et4N)2[(μ3-Se)]Fe3(CO)9, [(μ-H)2Fe3(μ3-Se)(CO)9], and [(μ3-Se)FeMo2(η5-C5H5)2(CO)7]

The cluster anion [Fe₃(μ₃-Se)(CO)₉]^2- (I) was isolated as a salt (Et₄N)₂[I] by the reaction of Fe(CO)₅ with Na₂Se in isopropanol. The protonated form, (μ-H)₂Fe₃(μ₃-Se)(CO)₉ (II), was obtained by acidifying the reaction mixture and used for the synthesis of the heterometallic cluster FeMo₂(μ₃-Se)(CO)₇Cp₂ (III), CP=η⁵-C₅H₅. The structure of I and III was established by X-ray diffraction analysis. Crystals I are monoclinic, a=14.210(3), b=11.547(3), c=19.831(2), Å, β=90.92(2)°, V_cell=3254(1) ų, space group P2/c, Z=4, d_calc=1.550 g/cm³, Syntex P2₁, λCuK_α, R(F)=0.1333 for 1264 F_hkl>6σ(F_hkl). Crystals III are monoclinic, a=20.440(5), b=12.771(3), c=16.342(4) Å, β=113.80(2)°, V_cell=3903(2) ų, space group P2₁/c, Z=8, d_calc=2.222 g/cm³, Syntex P2₁, λCuK_α, R(F)=0.0734 for 1116 F_hkl>4σ(F_hkl). The structure of II was inferred from the Mössbauer, IR, and¹H and⁷⁷Se NMR spectroscopy data.     

Primitive cubic packing of anions in Cs4[Re6Te8(CN)6]· 2H2O and Ba2[Re6Te8(CN)6] · 12H2O crystals

Crystal structures of Cs₄[Re₆Te₈(CN)₆]·2H₂O (1) and Ba₂[Re₆Te₈(CN)₆]· 12H₂O (2) are determined. Crystals 1 are orthorhombic, a = 14,282(1), b = 12.910(1), c = 18.040(1) Å, V_cell = 3326.3(8) ų, space group Pbcn, Z = 4, d_calc = 5.715 g/cm³, R(F) = 0.0482 for 3193 F_hkl > 4σ(F). Crystals 2 are triclinic, a = 9.671(3), b = 9.697(4), c = 11.039(4) Å, α = 89.86(3), β = 72.34(3), γ = 82.46(3)°, V_cell = 977.2(6) ų, space group P1, Z = 1, d^calc = 4.733 g/cm³, R(F) = 0.0490 for 3226 F_hkl > 4σ(F). In both structures, the [Re₆Te₈(CN)₆]^4? anions form a distorted primitive cubic packing with distances between the centers 9.02-9.63 Å in 1 and 9.70-11.04 Å in 2. The Cs⁺ cations in 1 lie near the face centers of the cubes formed by the onions. In 2, cation pairs (Ba²⁺)₂ bonded to two solvate water molecules are formed; the pairs lie at the centers of the anion cubes. In structures 1 and 2, there are shortened contacts between the tellurium atoms belonging to the neighboring anions (3.75-4.09 and 3.95-4.22 Å, respectively).     

Crystal structure of the ionic bioctahedral cluster complex [Ni(NH3)6]2.5NH4[Re12CS17(CN)6]·8.5H2O

A rhenium cluster complex [Ni(NH₃)₆]_2.5·NH₄[Re₁₂CS₁₇(CN)₆]·8.5H₂O is obtained and structurally described. The compound crystallizes in the triclinic space group P-1 with the unit cell parameters: a = 11.0856(13) Å, b = 15.242(2) Å, c = 21.232(3) Å, α = 90.158(4)°, β = 97.439(4)°, γ = 90.051(4)°, V = 3557.3(8) ų, Z = 2, d _calc = 3.287 g/cm³. The crystal structure represents a packing of [Ni(NH₃)₆]²⁺ and NH₄ ⁺ cations, [Re₁₂CS₁₇(CN)₆]^6? cluster anions, and crystallization water molecules bound by a system of hydrogen bonds.     

X-ray diffraction study of the clathrate [MnPy4(NO3)2)]·2Py and complex [MnPy3(NO3)2] formed in the pyridine (Py)-manganese nitrate system

A clathrate compound [MnPy₄(NO₃)₂]·2Py was synthesized and studied by single-crystal X-ray diffraction analysis (KM-4 diffractometer, CuK_α,ω/2? scan mode,? _max=78°). The unit cell is base-centered orthorhombic, space group Ccca, a=12.097(4), b=15.197(4), c=17.213(4) Å, V=3164(2) ų, Z=4, R=0.072, for 632 reflections and 107 parameters in the least-squares analysis. The host molecule has 222 symmetry. Two monodentate nitrato groups and four pyridine ligands are coordinated to Mn(II) along the symmetry axes (the former via O). The pyridine guest molecules lie in the cavities of the crystal framework. For [MnPy₃(NO₃)₂)], only unit cell parameters were determined: a=12.467(5), b=9.514(2), c=16.383(5) Å,β=108.93(4), V=1838(1) ų space group C2/c or Cc (according to extinctions). The pyridine-manganese nitrate system is shown to be analogous to the previously investigated Co, Ni, Cu, Zn, and Cd systems.     

Rb2[U(NH2)6], a Rubidium Hexaamidouranate(IV) obtained from the Reaction of UI3 with RbNH2 in Anhydrous Ammonia

The pyrophoric compound Rb₂[U(NH₂)₆] was obtained as a grey to black powder from the reaction of more than three equivalents of RbNH₂ with UI₃ in anhydrous liquid ammonia. During the process, U^III is oxidized to U^IV and ammonia is reduced under evolution of H₂. Rb₂[U(NH₂)₆] crystallizes in the cubic crystal system, space group Fm3 m, with the lattice parameter a = 9.7870(12) Å, V = 937.4(2) ų, Z = 4 at T = 293 K. It is isotypic to K₂PtCl₆. The compound contains the unprecedented hexaamidouranate(IV) anion [U(NH₂)₆]^2–.     

Unusual layer structure in an ion-paired compound containing tetra(isothiocyanate) cobalt(II) dianion and 4-nitrobenzylpyridinium: Crystal structure and magnetic properties

A new ion-paired compound [4NO₂BzPy]₂[Co(NCS)₄] (1) ([4NO₂BzPy]⁺ = 1-(4′-nitrobenzyl)pyridinium, NCS^? = isothiocyanate) is synthesized and characterized by elemental analysis, IR and UV-Vis spectra, ESI-MS and single crystal X-ray diffraction. Compound 1 is orthorhombic, space group Pbcn, with a = 13.188(2) Å, b = 8.458(1) Å, c = 29.281(4) Å, V = 3266.2(7) ų, D _calc = 1.468 g/cm³, Z = 4, F(000) = 1476, R ₁ = 0.0332. The [Co(NCS)₄]_2? anions form an unusual layer structure by S…N and S…Co interactions, while the [4NO₂BzPy]⁺ cations stack into a 1D column by the p…π stacking interaction in the solid state of 1. A magnetic measurement in the range 2–300 K shows a weak antiferromagnetic exchange with θ = ?2.42 K in 1.