Isomorphous crystal structures of 4,7,13,16,21,24-hexaoxo-1,10-diaziniabicyclo[8.8.8]·hexacosane bis(tribromide) and bis(bromoiodide)

Two compounds, 7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane bis(tribromide) and bis(bromodiiodide) — [H₂(Crypt-222)]²⁺·2Br ₃ ^? (I) and [H₂(Crypt-222)]²⁺·1.45(BrI₂)^?·0.4(Br₂I)^?·0.15 I ₃ ^? (II) — are prepared and characterized by single crystal XRD; the refinement of the second compound was more accurate. Isomorphous monoclinic structures (I, space group C2/c, Z = 4, a = 12.090, b = 15.833 Å, c = 15.732 Å, β = 95.83°; II, a = 12.548 Å, b = 16.417 Å, c = 15.748 Å, β = 94.53°) are solved by a direct method and refined in the anisotropic full-matrix approximation to R = 0.057 (I) and 0.044 (II) using all 2635 (I) and 2852 (II) measured independent reflections (automated CAD-4 diffractometer, λMoK _α). In the structures of I and II one of the trihalide anions sits at the inversion center i(000), and the second trihalide anion and the dication [H₂(Crypt-222)]²⁺ are situated at crystallographic axis 2. In the structure of II iodine is located in the center of trihalide anions, while the terminal atoms are disordered and are represented by a statistical combination of iodine and bromine atoms.     

4,7,13,16,21,24-hexaoxa-1,10-diazaniabicyclo[8.8.8]hexacosane tetra(nitrato-O)copper(II): Synthesis and crystal structure

A new crystalline complex salt, 4,7,13,16,21,24-hexaoxa-1,10-diazaniabicyclo[8.8.8]hexacosane tetra(nitrato-O)copper(II) [H₂(Crypt-222)]²⁺ · [Cu(NO₃)₄]^2?(I), is synthesized and studied using X-ray diffraction analysis (space group P2₁/c, a = 10.264 Å, b = 14.798 Å, c = 19.516 Å, β = 100.20°, Z = 4). The structure is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.032 for 4050 independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). Salt I exist in crystals as individual ions: the [Cu(NO₃)₄]^2? complex anion and the slightly disordered dication of 2.2.2-cryptand with two protonated nitrogen atoms. The Cu²⁺ cation has a square coordination somewhat distorted toward a flattened tetrahedron with four coordination bonds with the O atoms of the four NO ₃ ^? ligands. Trifurcate hydrogen bonds of the [H₂(Crypt-222)]²⁺ type are observed in the N-H(? O)₃ dication.     

4,7,13,16,21,24-Hexaoxa-1,10-diazoniabicyclo[8.8.8]-hexacosane Bis[tetrabromoiron(III)]: Synthesis and Crystal Structure

A new complex salt, 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]-hexacosane bis[tetrabromoiron(III)], [H₂(Crypt-222)]²⁺ · 2[FeBr₄]^? (I), is synthesized, and its crystal structure is studied using X-ray diffraction analysis (space group C2, a = 13.605 Å, b = 11.144 Å, c = 12.977 Å, β = 117.27°, Z = 2, direct method, full-matrix least-squares method in the anisotropic approximation, R = 0.074 for 2673 reflections, CAD4 automated diffractometer, λMoK _αradiation). In the structure of salt I, the tetrahedral [FeBr₄]^? anion is somewhat distorted. The 2.2.2-cryptand dication (with two protonated nitrogen atoms) lies on the crystallo-graphic axis 2and contains N⁺-H(?O)₃ trifurcate hydrogen bonds.     

Synthesis and crystal structure of (2.2.2-cryptand)potassium nitrate hydrate

(2.2.2-Cryptand)potassium nitrate hydrate, [K(Crypt-222)](NO₃) · 1.5H₂O (I) was synthesized and studied by X-ray diffraction method. Crystals I are triclinic (space group P ī, a = 11.262 Å, b = 12.033 Å, c = 12.181 Å, α = 60.48°, β = 86.17°, γ = 66.20°, Z = 2). The structure was solved by the direct method and refined by the full-matrix least-squares method in anisotropic approximation to R = 0.065 from 3377 independent reflections (CAD-4 automated diffractometer, λMoK _α). In complex I, the host-guest complex cation [K(Crypt-222)]⁺ has approximate D ₃ symmetry. The coordination polyhedron of the K⁺ cation is a two-base-centered trigonal prism, which is slightly distorted toward antiprism. The disordered NO ₃ ^? anions and water molecules are united by hydrogen bonds into infinite chains along the x-axis.     

Bis[(2.2.2-cryptand)potassium] tetrakis(isothiocyanato)cobalt(II) ethanol solvate with the 22% RbBr molar admixture: Synthesis and crystal structure

A new crystalline complex, bis[(2.2.2-cryptand)potassium] tetrakis(isothiocyanato)cobalt(II) ethanol solvate of the composition 2[K_0.89Rb_0.11(Crypt-222)]⁺ [Co(NCS)_3.78Br_0.22]^2? EtOH (I), was synthesized with 22 mol % RbBr and studied by X-ray diffraction. Complex I contains two mixed host-guest complex cations and the mixed complex anion. The triclinic structure of complex I (space group P1, a = 12.060 Å, b = 12.156 Å, c = 12.264 Å, α = 80.45°, β = 61.28°, γ = 71.98°, Z = 1) was solved by a direct method and refined by the full-matrix least squares in the anisotropic approximation to R = 0.066 for all 4400 independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). The [Co(NCS)_3.78Br_0.22]^2? anion is tetrahedral, and its two SCN^? ligands are partially replaced by two Br^? ligands. In structure I, two independent host-guest complex cations [K′(Crypt-222)]⁺ (K′ = (K_{1 ? δ} Rb_δ)⁺) are almost identical inverted reflection of each other and have approximate D ₃ symmetry. Their mixed cation K′ is coordinated by all eight heteroatoms (6O + 2N) of the 2.2.2-cryptand ligand, and the coordination polyhedron K′ is a dibase-centered trigonal prism (coordination number eight) slightly distorted toward an antiprism.     

Syntheses and crystal structures of (2.2.2-cryptand)potassium chloride and (2.2.2-cryptand)ammonium bromide<Subscript>(0.75)</Subscript>chloride<Subscript>(0.25)</Subscript> hydrates

Two new complexes were synthesized, namely, 7: 2 (2.2.2-cryptand)potassium chloride and (2.2.2-cryptand)ammonium bromide_(0.75)chloride_(0.25) hydrates: [M(Crypt-222)]⁺ · Hal^? · 3.5H₂O, where M = K, Hal = Cl (I) and M = NH₄, Hal = Br_0.75Cl_0.25 (II). The structures of two isomorphous crystals were studied by X-ray diffraction analysis. Trigonal (space group P \(\bar 3\), Z = 2) structures I (a = 11.763 Å, c = 11.262 Å) and II (a = 11.945 Å, c = 11.337 Å) were solved by direct methods and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.057 (I) and 0.065 (II) for all 2626 (I) and 1654 (II) independent measured reflections (CAD-4 automated diffractometer, λMoK _α). In structures I and II, the host-guest [M(Crypt-222)]⁺ complex cation lies on the threefold crystallographic axis and has the approximate D ₃ symmetry. In complex I, the coordination polyhedron of the K⁺ cation (CN = 8) is a bicapped trigonal prism somewhat distorted toward an antiprism. Complexes I and II contain H-bonded disordered cubes of the water molecules and the Cl^? or Br^? anions.     

<Emphasis Type="Italic">trans</Emphasis>-Tetraaqua(dibromo)nickel(II) 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane dibromide: Synthesis and crystal structure

A new complex, trans-tetraaqua(dibromo)nickel(II) 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane dibromide, [NiBr₂(H₂O)₄][H₂(Crypt-222)]Br₂ (I), was synthesized and its crystal sructure was studied by X-ray diffraction analysis: space group P2₁/c, a = 13.573, b = 8.328, c = 14.523 Å, β = 111.08°, Z = 2. Structure I was solved by a direct method and refined by full-matrix least-squares method in anisotropic approximation to R = 0.067 on 2684 independent reflections (CAD-4 autodiffractometer, λMoKα). The octahedral complex molecule [NiBr₂(H₂O)₄] and the [H₂(Crypt-222)]²⁺ dication (with two protonated N atoms) are located around the inversion center; the latter is statistically disordered. The dication contains trifurcate hydrogen bonds N-H(…O)₃. Crystal I also contains intermolecular hydrogen bonds O(w)-H…Br^?, which join the complex molecules [NiBr₂(H₂O)₄] and the Br^? anions into infinite “thick” layers parallel to the plane yz.     

Diaquabromo(18-crown-6)rubidium and triaqua(18-crown-6)barium dibromide monohydrate: Synthesis and crystal structures

Two complexes are synthesized: diaquabromo(18-crown-6)rubidium [RbBr(18-crown-6)(H₂O)₂] (I) and triaqua(18-crown-6)barium dibromide monohydrate [Ba(18-crown-6)(H₂O)₃]²⁺ 2Br^? · H₂O (II). The orthorhombic structure of compound I (space group Pnma, a = 10.124 Å, b = 15.205 Å, c = 12.544 Å, Z = 4) and the monoclinic structure of compound II (space group C 2/c, a = 17.910 Å, b = 10.315 Å, c = 14.879 Å, β = 123.23°, Z = 4) are determined by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.063 (I) and 0.042 (II) for all 2293 (I) and 3363 (II) independent measured reflections (CAD-4 automated diffractometer, λMoK _α). The complex molecule [RbBr(18-crown-6)(H₂O)₂] in compound I and the randomly disordered cation [Ba(18-crown-6)(H₂O)₃]²⁺ in compound II are of the host-guest type: their Rb⁺ or Ba²⁺ cation (its coordination number is nine) is located in the cavity of the 18-crown-6 ligand and coordinated by all six O atoms. In structure I, the coordination polyhedron of Rb⁺ is a distorted hexagonal pyramid with a triple apex at the Br^? ligand and two O atoms of the water molecules. In structure II, the Ba²⁺ polyhedron is a distorted hexagonal bipyramid with one apex at the O atom of the water molecule and the other split apex at two O atoms of water molecules.     

Synthesis and crystal structures of (2.2.2-cryptand)rubidium chloride and bromide hydrates

Two complexes, (2.2.2-cryptand)rubidium chloride and bromide hydrates [Rb(Crypt-222]Hal · 3.5H₂O (Hal = Cl (I) and Br (II)), are synthesized. The structures of isomorphic crystals of compounds I and II are studied by X-ray diffraction analysis. The crystals are trigonal: space group P \(\overline 3 \), Z = 2; I: a = 11.810 Å, c = 11.302 Å; II: a = 11.890 Å, c = 11.402 Å. The structures are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.060 (I) and 0.077 (II) for 2650 (I) and 2700 (II) independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). In crystals of complexes I and II, the [Rb(Crypt-222)]⁺ cation of the host-guest type lies on the crystallographic axis 3 and has the approximate symmetry D ₃. In complexes I and II, the coordination polyhedron of the Rb⁺ cation is a two-base-centered trigonal prism somewhat distorted to an antiprism. The crystals of compounds I and II contain H-bonded disordered cubes of the water molecules and Cl^? or Br^? anions.     

4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]-hexacosane tetra(nitrato)zinc(II): Synthesis and crystal structure

A new complex salt 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]-hexacosane tetra(nitrato)zinc(II), [H₂(Crypt-222)][Zn(NO₃)₄]^2?, is synthesized and studied by X-ray diffraction analysis: space group $P\bar 1$ , a = 10.556 Å, b = 11.089 Å, c = 14.536 Å, α = 104.63°, β = 109.23°, γ = 99.22°, Z = 2. The structure is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.031 for 3897 independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). The structural units of the crystal are the [Zn(NO₃)₄]^2? complex anion and somewhat disordered 2.2.2-cryptand dication (with two protonated nitrogen atoms). The Zn²⁺ cation forms four strong coordination bonds with the O atoms of four NO ₃ ^? ligands and four weak (secondary) bonds with the second O atoms of these ligands. While ignoring the latter, the Zn²⁺ cation has a strongly distorted tetrahedral configuration. The [H₂(Crypt-222)]²⁺ dication contains trifurcate hydrogen bonds N-H(…O)₃.     

Disordered crystal structure of 4,7,13,16,21,24-hexaoxa-1-aza-10-azoniabicyclo[8.8.8]hexacosane isocyanurate

X-ray spectral analysis has been applied to study the crystal structure of 4,7,13,16,21,24-hexaoxa-1-aza-10-azoniabicyclo[8.8.8]hexacosane isocyanurate of an unusual composition: [H_1.2(Crypt-222)]^1,2+ · [H_0.8(Crypt-222)]^0.8+·2(C₃H₂N₃O₃)^? (I). The structure of I (space group C2/c, a = 37.840 Å, b = 13.760 Å, c = 19.456 Å, β = 91.21°, Z = 8) was solved by a direct method and refined by the full-matrix least-squares technique in the anysotropic approximation up to R = 0.119 over 6500 independent reflections measured (autodiffractometer CAD-4, λ-MoK _α). The structure of I has two independent cations of 2.2.2-cryptand linked by the proximate pseudo-center of inversion and they have a rare conformation of exo-exo type, in which H atom or lone pair at both their node atoms N are directed outward their cavity. In the structure of I, all H atoms at N atoms of cations and half of H atoms of isocyanurate anions are disordered and have the populations of positions 0.7, 0.5, and 0.3. There is a developed system of interionic hydrogen bonds in the crystal structure of I.     

Synthesis and crystal structure of (2.2.2-cryptand)(nitrato-O,O’)lead(II) nitrate monohydrate

A new complex, (2.2.2-cryptand)(nitrato-O,O’)lead(II) nitrate monohydrate [Pb(NO₃)(Crypt-222)]⁺ · NO ₃ ^? · H₂O, is synthesized and characterized by X-ray crystallography. The structure of the complex (space group Pbca, a = 14.196 Å, b = 14.001 Å, c = 26.745 Å, Z = 8) is solved by direct methods and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.073 for 3474 unique reflections (CAD4 automated diffractometer, λMOK _α). The structure contains the host-guest complex cation [Pb(NO₃)(Crypt-222)]⁺. The Pb²⁺ cation is located in the cavity of the 2.2.2-cryptand ligand and is coordinated by all eight heteroatoms (6O + 2N) of the cryptand ligand and two O atoms of the NO ₃ ^? ligand. The coordination polyhedron of the Pb²⁺ cation (ten-coordinate) is a strongly distorted hexagonal bipyramid with a base of four O atoms and two N atoms of the cryptand ligand and with two bifurcated axial vertices at two O atoms of the nitrate ligand and two O atoms of the cryptand ligand. The disordered NO ₃ ^? anion and the water molecule are linked by hydrogen bonds.     

Disordered crystal structure of 4,7,13,16,21,24-hexaoxa-1-aza-10-azoniabicyclo[8.8.8]hexacosane perchlorate monohydrate

The disordered crystal structure of 4,7,13,16,21,24-hexaoxa-1-aza-10-azoniabicyclo[8.8.8]-hexacosane perchlorate monohydrate, [H(Crypt-222)·H₂O]⁺·ClO ₄ ^? (I), has been determined by XRD. The triclinic structure of I (space group \(P\overline 1 \), a = 9.748 Å, b = 10.570 Å, c = 13.820 Å; α = 109.40°, β = 109.75°, γ = 93.04°, Z = 2) was solved by direct methods and refined by full-matrix least-squares in the anisotropic approximation to R = 0.072 over all 3675 independent reflections collected (CAD-4 automatic diffractometer, λCuK_α). This compound is the first crystal salt containing the 2.2.2-cryptand cation with one protonated nitrogen atom that was synthesized and structurally investigated.     

Synthesis and crystal structure of hexa(nitrato-<Emphasis Type="Italic">O,O</Emphasis>′)dysprosium(III) Bis[4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane] nitrate dihydrate

A new complex salt 2[H₂(Crypt-222)]²⁺ · [Dy(NO₃)₆]^3? · NO ₃ ^? · 2H₂O is synthesized, and its crystal structure is studied by X-ray diffraction analysis (space group R \(\bar 3\), a = 11.445 Å, c = 38.981 Å, Z = 3; direct method, full-matrix least-squares method in the anisotropic approximation, R = 0.027 for 3555 independent reflections; CAD4 automated diffractometer, λMoK _α radiation). The [Dy(NO₃)₆]^3? anion and 2.2.2-cryptand dication lie on axis \(\bar 3\). The [Dy(NO₃)₆]^3? ligand in the [Dy(NO₃)₆]^3? anion is disordered. The Dy³⁺ cation has slightly distorted octahedral coordination with all six split vertices at the O atoms of the six symmetrically equivalent disordered NO ₃ ^? ligands.     

4,7,13,16,21,24-Hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane Bis[dibromodichloroiron(III)]: Synthesis and Crystal Structure

A novel complex salt, namely, 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane bis[dibromodichloroiron(III)] [H₂(Crypt-222)]²⁺[FeBr₂Cl₂] ₂ ^? (I), was synthesized and structurally characterized by X-ray diffraction analysis (monoclinic crystal system, a = 13.550 Å, b = 11.018 Å, c = 12.813 Å, β = 117.52°, space group C2, Z = 2). The structure was solved by the direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.089 from 2593 independent reflections (CAD4 automated diffractometer, λMoKα radiation). In the crystal structure I, four bifurcate positions of Br and Cl in the tetrahedral anion [FeBr₂Cl₂]^? are a randomly disordered mixture of these atoms. The dication of 2.2.2-cryptand (with two protonated N atoms) in the crystallographic axis 2 contains trifurcate N⁺-H (?O)₃ hydrogen bonds.     

The Cocrystallization of the Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and Triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl,Br, NO3) Phases with the Coexistence of [Ta6Br12]2+ and [Ta6Br12]4+ in the Latter

Cubic [Ta₆Br₁₂(H₂O)₆][CuBr₂X₂]·10H₂O and triclinic [Ta₆Br₁₂(H₂O)₆]X₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O (X = Cl, Br, NO₃) cocrystallize in aqueous solutions of [Ta₆Br₁₂]²⁺ in the presence of Cu²⁺ ions. The crystal structures of [Ta₆Br₁₂(H₂O)₆]Cl₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 1 ) and [Ta₆Br₁₂(H₂O)₆]Br₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta₆Br₁₂]²⁺ in the [Ta₆Br₁₂(H₂O)₆]²⁺ cation and [Ta₆Br₁₂]⁴⁺ in trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]. Average bond distances in the [Ta₆Br₁₂(H₂O)₆]²⁺ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Brⁱ , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Brⁱ , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta₆‐Br₁₂(OH)₄(H₂O)₂]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Brⁱ, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H₂O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Brⁱ, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H₂O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta₆Cl₁₂]²⁺ oxidized to [Ta₆Cl₁₂]⁴⁺ , whereas [Nb₆X₁₂]²⁺ clusters were not affected by the Cu²⁺ ion.     

Crystal structure of [Cu2(Edta)(Py)2(H2O)2] · 2H2O and [Cu(Im)6]{;Cu(Im)4[Cu(Edta)(Im)]2} · 6H2O, Products of the interaction of (Ethylenediaminetetraacetato)diaquadicopper(II) with pyridine and imidazole

The crystals of [Cu₂(Edta)(Py)₂(H₂O)₂] · 2H₂O (I) and [Cu(Im)₆]{;Cu(Im)₄[Cu(Edta)(Im)]₂} · 6H₂O (II) were isolated as a result of the reaction of an aqueous solutions of Cu₂(Edta) · 4H₂O with pyridine or imidazole, respectively. The crystals were studied by X-ray diffraction. The crystals of I are monoclinic, a = 12.682 Å, b = 6.788 Å, c = 14.834 Å, β = 91.44°, Z = 2, space group P2₁/n. The crystals of II are triclinic, a = 9.118 Å, b = 14.889 Å, c = 15.130 Å, α = 72.59°, β = 72.94°, γ = 82.54°, Z = 1, space group P{ie241-1}. In the centrosymmetric binuclear complex molecule of I, an N atom and two O atoms of the Edta ligand are coordinated to each Cu atom (Cu-N, 2.046 Å; Cu-O, 1.941 and 1.954 Å). The N atom of the pyridine molecule (Cu-N, 1.993 Å) completes the base of an elongated tetragonal pyramid (4 + 1) with the O atom of the H₂O molecule in the apex (Cu-O(w), 2.244 Å). The crystals of II are built of centrosymmetric complex cations [Cu(Im)₆]²⁺ (Cu(1)-N, 2.469, 2.021, and 2.056 Å), centrosymmetric trinuclear complex anions {;Cu(Im)₄[Cu(Edta)(Im)]₂}^2?, and crystal water molecules. In the anion, the central fragment [Cu(Im)₄]²⁺ (Cu(2)-N, 1.985 and 2.023 Å) is bonded to two peripheral complexes [Cu(Edta)(Im)]^2? through atoms O of the Edta ligand (Cu(2)-O, 2.615 Å). In the [Cu(Edta)(Im)]^2? fragment of the complex anion, the Cu(3) atom is bonded to the Edta ligand through the two N atoms and three O atoms (Cu(3)-N, 1.970 and 2.071 Å; Cu(3)-O, 1.966, 1.969, and 2.238 Å) and with the imidazole molecule, through an N atom (Cu(3)-N, 2.397 Å). The coordination polyhedra of the three copper atoms (Cu(1)-Cu(3)) in the structure of II are elongated tetragonal bipyramids (4 + 2). In the structures studied, Edta^4? is a hexadentate chelating/bridging ligand. However, the coordination mode of the ligand in these structures is different: in the binuclear complex I, the Edta ligand is coordinated to each Cu atom through an N atom and two O atoms with the formation of two chelate rings (symmetric (trans) coordination mode), whereas, in the trinuclear complex II, the Edta ligand is coordinated to the Cu(2) atom through an O atom and to the Cu(3) atom through the two N atoms and three O atoms with the formation of three chelate rings (asymmetric (cis) coordination mode).     

Oxidation of coordinated ethylenediamine in platinum(IV) complexes with bromine. Crystal structures of [Pt(en)Py2Br2]Br2 · H2O, [Pt(HN-C(O)-C(O)-NH)Py2Br2] · H2O, and [Pt(en)PyBr3]NO3

Heating of an aqueous solution of [Pt(en)Py₂Cl₂]Cl₂ · 2H₂O (I) with KBr excess leads to the formation of [Pt(en)Py₂Br₂]Br₂ · H₂O (II). The interaction of a solution of II with bromine water results in the precipitation of polybromide ([Pt(en)Py₂Br₂]Br₂ · Br₂), which within a few days in the reaction solution partly transforms into oximide platinum(IV) complex, [Pt(HN-C(O)-C(O)-NH)Py₂Br₂] · H₂O (III). Complex [Pt(en)PyBr₃]Br · H₂O (IV) with an impurity of II was prepared by reacting KBr excess and the product of [Pt(en)Py₂]Cl₂ oxidation with chlorine in 0.05 N HCl. The action of HNO₃ on the solution of IV produced a nitrate derivative ([Pt(en)PyBr₃]NO₃, V). Complex IV, unlike II, does not react with bromine. The IR spectra of all the obtained compounds were recorded. Complexes II, III, and V were studied by X-ray crystallography. The crystals of II are monoclinic, space group P2₁/c, a = 15.640(2) Å, b = 9.345(1) Å, c = 14.167(2) Å, β = 102.63(1)°, V = 2020.5(5) ų, Z = 4, R _hkl = 0.033. The crystals of III are triclinic, space group P $\bar 1$ , a = 7.108(1) Å, b = 10.946(1) Å, c = 11.020(2) Å, α = 83.63(1)°, β = 80.31(1)°, γ = 75.02(1)°, V = 814.4(2) ų, Z = 2, R _hkl = 0.033. In the near-planar five-membered chelate ring (torsion angle NCCN is 7°), the C-O distances (1.23(1) Å) correspond to double bonds; the C-C (1.53(1) Å) and C-N (1.31(1) Å), distances correspond to ordinary bonds. The crystals of V are monoclinic, space group P2₁/c, a = 8.306(2) Å, b = 8.995(2) Å, c = 20.231(4) Å, β = 97.48(2)°, V = 1498.6(6) ų, Z = 4, R _hkl = 0.037.     

Synthesis and study of hydrogen hexamolybdonickelate and hydrogen hexamolybdozincate with the cobaltammine cation

[Co(NH₃)₆] · H₂[NiMo₆O₁₈(OH)₆] · 6H₂O (I) and [Co(NH₃)₆] · H₂[ZnMo₆O₁₈(OH)₆] · 6H₂O (II) have been synthesized and studied by mass spectroscopy, thermogravimetry, and X-ray powder diffraction. The crystals of compounds I and II are monoclinic, Z = 1; for compound I: a = 16.10 Å, b = 5.58 Å, c = 12.22 Å, β = 117.86°, V = 1045.14 ų, and ρ_calcd = 2.26 g/cm³; for compound II: a = 16.12 Å, b = 5.52 Å, c = 12.12 Å, β = 117.90°, V = 1043.21 ų, and ρ_calcd = 2.21 g/cm³.     

Crystal structure of tris[(2.2.2-cryptand)× (nitrato-O,O′)lead(II)] pentakis(nitrato-O,O′)lead(II)

A novel coordination compound tris[(2.2.2-cryptand)(nitrato-O,O′)lead(II)] pentakis(nitrato-O, O′)lead(II), 3[Pb(NO₃)(Crypt-222)]⁺·[Pb(NO₃)₅]^3? (I) has been prepared and studied by the single crystal X-ray diffraction technique. The crystals of I are monoclinic: space group Pc, a = 25.944 Å, b = 18.389 Å, c = 17.145 Å, β = 93.33°, Z = 4. The structure of I has been solved by the direct and heavy atom methods and refined in a full-matrix anisotropic-isotropic approximation to R = 0.122 for the total of 11145 measured reflections (automated diffractometer CAD-4, λMoK _α). The structure of I includes six independent host-guest complex cations [Pb(NO₃)(Crypt-222)]⁺ and two independent complex anions [Pb(NO₃)₅]^3?. Coordination number of the cation Pb²⁺ equals ten in all these complex ions, and its coordination polyhedron in the first of them is a strongly distorted “hexagonal bipyramid” with two forked vertices, while for the latter ones it is a strongly distorted “square pyramid” with all five vertices forked.