Crystal and molecular structures of bis(2,2,6,6-tetramethyl-3-methylaminoheptan-5-onate) copper(II) and nickel(II)

Two bis-chelates M(tmih)₂ (M = Cu(II), Ni(II), tmih = (CH₃)₃C(NCH₃)CHCOC(CH₃)₃)^? are synthesized and their crystal structures are determined using XRD (Bruker APEX-II diffractometer with a CCD detector, λMoK _α, λCuK _α, graphite monochromator, T = 240(2) K and 296(2) K): Cu(tmih)₂ (I) (space group P2₁/c, a = 12.9670(8) Å, b = 18.4921(9) Å, c = 11.0422(6) Å, β = 93.408(4)°, V = 2643.1(3) ų, Z = 4) and Ni(tmih)₂ (II) (space group P2₁/c, a = 12.810(2) Å, b = 18.529(2) Å, c = 11.243(2) Å, β = 91.959(7)°, V = 2667.1(6) ų, Z = 4). The complexes are isostructural; the coordination polyhedron of metal atoms is a flattened tetrahedron formed from two O atoms (Cu-O of 1.901(2) Å, 1.892(2) Å, Ni-O of 1.845(2) Å, 1.833(2) Å) and two N atoms (Cu-N of 1.976(3) Å, 1.972(3) Å, Ni-N of 1.911(2) Å, 1.920(2) Å) of the ligand; the chelate OMN angles (M = Cu(II), Ni(II)) are in the 87.4–93.1° range; the OMO and NMN angles are 162.2° and 167.2° in I, 171.1° and 173.2° in II. The complexes have the molecular structures formed from isolated molecules bonded by van der Waals interactions. Using a quantum chemical hybrid M06 method, the structures of copper(II) chelates with the H, CH₃, CH₂CH₃, CH(CH₃)₂, and C(CH₃)₃ substituents at the nitrogen atom are calculated. Found that with a bulky substituent at the nitrogen atom, the formation of chelates is hindered due to the intraligand repulsion between the atoms of this substituent and the tert-butyl group.     

Acid Co(II) and Ni(II) trifluoroacetate complexes: Synthesis and crystal structure

Anhydrous and partially hydrated acid trinuclear trifluoroacetates of divalent transition metals of the composition [M₃(CF₃COO)₆(CF₃COOH)₆)](CF₃COOH) and [M₃(CF₃COO)₆(CF₃COOH)₂(H₂O)₄)](CF₃COOH)₂, respectively, where M = Co (I, III) Ni (II, IV), were synthesized and studied by X-ray diffraction. Complexes I and II were obtained by crystallization from solutions of M(CF₃COO)₂ · 4H₂O in trifluoroacetic anhydride; complexes III and IV were synthesized under the same conditions with the use of 99% trifluoroacetic acid as a solvent. Crystals I are triclinic: space group $P\bar 1$ , a = 13.199(6) Å, b = 14.649(6) Å, c = 15.818(6) Å, α = 90.04(4)°, β = 114.32(4)°, γ = 108.55(4)°, V = 2611.3(19) ų, Z = 2, R = 0.0480. Crystals II are trigonal: space group $R\bar 3$ , a = 13.307(2) Å, c = 53.13(1) Å, V = 8148(2) ų, Z = 6, R = 0.1112. Crystals III are triclinic: space group $P\bar 1$ , a = 9.001(8) Å, b = 10.379(9) Å, c = 12.119(9) Å, α = 83.67(5)°, β = 72.33(5)°, γ = 83.44(5)°, V = 1068.3(15) ų, Z = 1 Å, R = 0.1031. Crystals IV are triclinic: space group $P\bar 1$ , a = 9.121(18) Å, b = 10.379(2) Å, c = 12.109(2) Å, α = 84.59(3)°, β = 72.20(3)°, γ = 82.80(3)°, V = 1080.94(40) ų, Z = 1, R = 0.0334.     

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).     

Thulium(III) trifluoroacetates Tm(CF3COO)3 · 3H2O and Tm2(CF3COO)6 · 2CF3COOH · 3H2O: Synthesis and crystal structure

Thulium trifluoroacetate compounds have been synthesized, Tm(CF₃COO)₃ · 3H₂O (I) and Tm₂(CF₃COO)₆ · 2CF₃COOH · 3H₂O (II). The structure of I has been refined by the Rietveld method on the basis of the structural data for Cd(CF₃COO)₃ · 3H₂O. The structure of II has been solved in a single-crystal X-ray diffraction study. Compound I has been studied by thermal analysis. Crystals of I and II are monoclinic: for I a = 9.062(2) Å, b = 18.678(3) Å, c = 9.687(2) Å, β = 113.93(1)°, Z = 2, space group P2₁/c, R ₁ = 0.062; for II a = 8.560(4) Å, b = 19.866(5) Å, c = 20.813(7) Å, β = 101.69(4)°, Z = 8, space group C2/c, R ₁ = 0.0392. In the molecular structure of I, thulium atoms are bonded in pairs through four bridging trifluoroacetate anions to form dimers. The coordination polyhedron of the thulium atom also includes the three O atoms of the water molecules and the O atom of the monodentate trifluoroacetate group; the coordination number of the thulium atom is eight. In the chain structure of II, there are two crystallographically independent thulium atoms with coordination numbers 8 and 9. The coordination polyhedra of the Tm(1) and Tm(2) atoms are a distorted monocapped tetragonal antiprism and a distorted tetragonal antiprism, respectively. The Tm-O bond lengths are in the range 2.28(1)–2.85(2) Å. The thulium atoms are bound into chains through carboxylate groups. These chains are linked into layers through hydrogen bonds.     

Heteroligand zinc(II) and copper(II) complexes with naphthylacetic acid and monoethanolamine: Syntheses and crystal structures

New heteroligand Cu(II) and Zn(II) complexes with the α-naphthylacetic acid anion (NAA) and monoethanolamine (MEA), [M(NAA)₂(MEA)₂] (M = Cu²⁺, (I), Zn²⁺ (II)), are synthesized. The crystal structures of the obtained complexes are determined by X-ray diffraction analysis (CIF files CCDC 984097 (I) and 930946 (II)). The crystals are monoclinic, for I: a = 18.8140(9) Å, b = 4.82500(14) Å, c = 16.0360(7) Å, β = 115.135(6)°, V = 1317.87(11) ų, space group P2₁/c, Z = 2; for II: a = 32.9760(14) Å, b = 5.0911(3) Å, c = 15.7994(10) Å, β = 94.418(5)°, V = 2644.6(3) ų, space group C2/c, Z = 4. In the structure of complex I, the Cu²⁺ ion arranged in the symmetry center is coordinated at the vertices of the distorted octahedron by the oxygen atoms of two NAA molecules (Cu-O(2) 2.019(4) Å) and two MEA molecules. The latter is the bidentate-chelating ligand and coordinates the metal through the O and N atoms to form the five-membered metallocycle (Cu-O(3) 2.457(5), Cu-N(1) 1.986(5) Å). In complex II, the Zn atom (on axis 2) is coordinated at the vertices of the distorted tetrahedron by the oxygen atoms of two NAA molecules (Zn-O(2) 1.976(4) Å) and the nitrogen atoms of two MEA molecules (Zn-N 2.034(6) Å). The character of the interaction of coordinated NAA and MEA ligands and methods for packing complexes I and II are considered on the basis of the structural data.     

Mixed-ligand complexes based on asymmetric gadolinium β-diketonates: Synthesis, crystal structure, and theoretical modeling

Mixed-ligand complexes of asymmetric gadolinium β-diketonates with 2,2′-bipyridyl (Bipy)—[Gd(Pa)₃(Bipy)] (HPa is pivaloylacetone) (I) and [Gd(Pta)₃(Bipy)] (HPta is pivaloyltrifluoroacetone) (II)-have been obtained by direct interaction of initial reagents and their structures have been studied by X-ray crystallography. Crystals of I are monoclinic: a = 9.536(1) Å, b = 15.037(1) Å, c = 13.280(1) Å, β = 109.56(1)°, V = 1798.7(3) ų, Z = 2, space group P2₁. Crystals of II are triclinic: a = 9.6696(17) Å, b = 12.1348(9) Å, c = 18.243(3) Å, α = 100.257(12)°, β = 103.997(2)°, γ = 101.438(11)°, V = 1977.4(5), Z = 2, space group P $\bar 1$ . The coordination polyhedron of the central gadolinium atom in I and II is a distorted square antiprism formed by six oxygen atoms of the three β-diketonate ligands (av. Gd-O, 2.35(2) and 2.351(5) Å in I and II, respectively) and two nitrogen atoms of the Bipy ligand (av. Gd-N, 2.47(2) and 2.584(7) Å in I and II, respectively). Although the molecular structures of these complexes are similar, they have different crystal packings. In II, the planes of the Bipy ligands of neighboring molecules related by an inversion center are bound by stacking interaction (the distance between the Bipy planes is 3.45 Å). The structure and properties of these mixed-ligand complexes have been discussed based on the results of quantum-chemical density functional theory calculations (DFT/B3PW91). The nature of the substituents in the β-diketonate ligand has an effect on the structure and properties of the complexes. The correlation between the Gd-Dik and Gd (Dik)₃-Bipy bond energies has been studied.     

Mixed-ligand complexes of alkaline-earth metal trifluoroacetates with monoethanolamine

The mixed-ligand complexes of the formula [M(CF₃COO)₂(MEA) _n ] (MEA is monoethanolamine; M = Ca (I) and Sr (II), n = 1.5; M = Ba (III), (n = 1) were obtained from appropriate salts M(CF₃COO)₂ · nH₂O and MEA in ethanol. Complexes I–III were characterized by elemental analysis data and IR spectra. Slow crystallization of a solution of complex III in air gave a single crystal of the formula [Ba(CF₃COO)₂(MEA)(H₂O)], which is a coordination polymer with C.N.(Ba) 9 (X-ray diffraction data). Thermal analysis showed that complexes I–III decompose under argon and in air to the corresponding fluorides at T < 400°C.     

Crystal structures of 3-phenylpropenal thiosemicarbazone and its nickel and zinc chelates

3-Phenylpropenal thiosemicarbazone hydrate C₆H₅-HC=CH-CH=N-NH-C(S)-NH₂ · H₂O (HL · H₂O, I) and two chelates [Ni(L)₂] · nCH₃OH (II) and [Zn(L)₂] (III) are studied by X-ray diffraction. The crystals of I are orthorhombic: a = 6.227(1) Å, b = 7.763(2) Å, c = 25.585(5) Å, β = 90°, space group P2₁2₁2₁, Z = 4, R = 0.0426. A nonplanar molecule of I has an E conformation. The crystals of II are triclinic: a = 6.551(2) Å, b = 10.752(3) Å, c = 10.885(3) Å, α = 64.751(5)°, β = 82.753(5)°, γ = 89.857(5)°, space group, Z = 1, R = 0.0661. In a centrosymmetric molecule of II, the central atom coordinates two deprotonated ligands L through the immine nitrogen atom and thioamide sulfur atom at the vertices of a distorted square. The crystals of III are monoclinic: a = 25.342(2) Å, b = 9.150(2) Å, c = 21.340(3) Å, α = 90°, β = 111.84(2)°, γ = 90°, space group C2/c, Z = 8, R = 0.0556. In a molecule of complex III, two deprotonated bidentate ligands L are coordinated by the zinc ion through the immine nitrogen atoms and thioamide sulfur atoms to form a distorted tetrahedron at the central atom. In both II and III, ligand L after coordination by the metal ion changes the E conformation with respect to the N(1)-C(2) bond for the Z conformation. In crystals I-III, molecules are packed to form infinite layers parallel to the planes (001) and (010).     

Crystal structure of two complexes containing tris-(β-diketonato)magnate anion

Single crystal XRD is used to determine the structures of the complexes (H₂TMEDA)[Mg(ptac)₃]₂ (1, TMEDA = Me₂N(CH₂)₂NMe₂, ptac = ^t BuCOCHCOCF₃) and (H₂TMEDA)[Mg(hfac)₃](hfac) (2, hfac = CF₃COCHCOCF₃) at a temperature of 150 K. The crystallographic data for complex 1: a = 10.2919(3) Å, b = 10.9492(4) Å, c = 15.4159(6) Å, α = 87.117(1)°, β = 89.686(1)°, γ = 79,864(1)°, space group $P\bar 1$ Z = 1, R = 0.0573; for complex 2: a = 12.9446(2) Å, b = 23.0035(4) Å, c = 13.1473(3) Å, β = 98.779(1)°, space group P2₁/n, Z = 4, R = 0.0605. The structures are ionic; the metal atom coordinates six oxygen atoms of three β-diketonate ligands. The distances Mg-O in complex 1 are in the range 2.036(2)–2.0920(19) Å; the same distances in complex 2 are in the range 2.051(2)–2.076(2) Å. The spatial packing is determined by the system of hydrogen bonds between the (H₂TMEDA)²⁺ cations and [Mg(ptac)₃]^? (1) or hfac^? (2) anions. A thermogravimetric study of complex 1 is carried out.     

Synthesis and molecular and crystal structures of binuclear complexes of Sm(III), Eu(III), Gd(III), Tb(III), and Dy(III) nitrates with 4,4,10,10-tetramethyl-1,3,7,9-tetraazospiro[5.5]undecane-2,8-dione

Binuclear complexes of Sm(III), Eu(III), Gd(III), Tb(III), and Dy(III) nitrates with 4,4,10,10-tetramethyl-1,3,7,9-tetraazospiro[5.5]undecane-2,8-dione (C₁₁H₂₀N₄O₂, SC)—[Sm(NO₃)₃(SC)(H₂O)]₂(I), [Eu(NO₃)₃(SC)(H₂O)]₂ (II), [Gd(NO₃)₂(SC)(H₂O)₃)]₂(NO₃)₂ (III), [Tb(NO₃)₃(SC)(H₂O)]₂ (IV), [Dy(NO₃)₃(SC)(H₂O)]₂ (V), are synthesized, and their X-ray diffraction analyses are carried out. The crystals of complexes I–V are monoclinic: space group P2₁/n for III and P2₁/c for I, II, IV, and V. In centrosymmetric coordination complexes II, III, IV, and V, the Ln atoms are coordinated by two O(1) and O(2) atoms of two molecules of the SC ligands bound by a symmetry procedure (1 ? x, ?y, 1 ? z), three bidentate nitrate anions, and a water molecule. The coordination numbers of the metal atoms are equal to 9, and the coordination polyhedra are considerably distorted three-capped trigonal prisms, whose bases include the O(1), O(2), O(12) and O(3), O(7), O(9) atoms. The dihedral angle between the bases of the prism is 18°, and that between the mean planes of the side faces is 55°–71° for I, 17° and 55°–71° for II, 16° and 55°–70° for IV, and 16° and 55°–70° for V. The Sm...Sm distance in complex I is 9.44 Å, Eu...Eu in II is 9.42 Å, Tb...Tb in IV is 9.36Å, and Dy...Dy in V is 9.36Å. The gadolinium atom in complex III is coordinated by two oxygen atoms of two ligand molecules bound by a symmetry procedure (?x, ?y + 1, ?z + 1), two bidentate nitrate anions, and three water molecules. One of the nitro groups in compound III is localized in the external coordination sphere of the metal. The coordination number of gadolinium is 9, and the coordination polyhedron is a significantly distorted three-capped trigonal prism, whose base includes the O(1), O(2), O(7) and O(4), O(5), O(9) atoms. The dihedral angle between the bases of the prism is 22.8°, and that between the mean planes of the side faces is 53°–72°. The Gd...Gd distance in complex III is 9.17 Å.     

Synthesis and crystal structures of two azido-bridged copper(II) complexes with schiff bases

Two new end-on azido-bridged dinuclear copper(II) complexes with the formula [Cu(μ_1,1-N₃)₂(IEP)₂] (I) and [Cu(μ_1,1-N₃)₂(EMP)₂] (II), where IEP and EMP are the deprotonated forms of 2-[1-(2-isopropylaminoethylimino)ethyl]phenol and 2-ethoxy-6-[(2-methylaminoeth-ylimino)methyl]phenol, respectively, were synthesized. Both complexes were characterized by elemental analyses and IR spectra. The crystal structures were determined by the X-ray diffraction. The crystal of I is monoclinic: space group P2₁/c, a = 9.662(2), b = 15.282(3), c = 10.639(2) Å, β = 115.418(10)°, V = 1418.9(5) ų, Z = 2. The crystal of II is monoclinic: space group P2₁/n, a = 12.588(2), b = 7.705(1), c = 14.481(2), β = 91.736(5)°, V = 1403.9(2) ų, Z = 2. The two Cu atoms in each complex are bridged by two end-on azide groups. Each Cu atom is in a square pyramidal coordination. The Cu…Cu distances are 3.230(2) Å in I and 3.150(2) Å in II.     

Crystal and molecular structures of ZnPhen(C2H5OCS2)2 and Zn(2,2′-Bipy)(n-C4H9OCS2)2 mixed-ligand coordination compounds

ZnPhen(EtOCS₂)₂ (I) and Zn(2,2′-Bipy)(n-BuOCS₂)₂ (II) mixed-ligand complexes have been synthesized. The structures were solved from X-ray diffraction data (CAD-4 and X8-APEX diffractometers, MoK _α radiation, 1879 and 3637 F _hkl , R = 0.0374 and 0.0315). Crystals I are monoclinic with parameters a = 11.678(3) Å, b = 19.215(3) Å, c = 9.655(1) Å; β = 101.23(1)°; V = 2125.0(7) ų; Z = 4, space group P2₁/c; crystals II are triclinic with parameters a = 8.7875(3) Å, b = 11.833(1) Å, c = 13.3454(6) Å; α = 112.154(2)°, β = 108.503(1)°, γ = 92.787(2)°; V = 1196.2(1) ų; Z = 2, space group 1 $P\bar 1$ . The structures are composed of discrete mononuclear molecules. The polyhedra of the Zn atoms are distorted trigonal bipyramids N₂S₃ formed by coordination of the N atoms of Phen or 2,2′-Bipy molecules and sulfur atoms of the monodentate and cyclic bidentate xanthogenate ligand. In structures I and II, dimer assemblies are formed by π-π interactions of Phen or 2,2′-Bipy molecules.     

Crystal structures of bis(AZIDO)bis(2-morpholin-4-ylethylamino)copper(II) and bis{2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl] phenolato}copper(II)

Two new copper(II) complexes [Cu(MEA)₂(N₃)₂] (1) and [Cu(BMP)₂] (2), where MEA and BMP are 2-morpholin-4-ylethylamine and 2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl]phenolate respectively, are prepared and characterized using elemental analysis, FT-IR spectroscopy, and X-ray single crystal diffraction. The crystal of 1 belongs to the triclinic system, space group P-1, with a = 6.661(2) Å, b = 8.440(3) Å, c = 8.913(3) Å, α = 102.032(3)°, β = 107.899(2)°, γ = 98.242(3)°, V = 454.6(3) ų, Z = 1, D _c = 1.490 g/cm³, R ₁ = 0.0226, and wR ₂ = 0.0564. The crystal of 2 belongs to the monoclinic system, space group P2₁/c, with α = 7.0707(7) Å, b = 15.438(1) Å, c = 14.227(1) Å, β = 96.659(2)°, V = 1542.5(3) ų, Z = 2, D _c = 1.821 g/cm³, R ₁ = 0.0437, and wR ₂ = 0.1041. In each complex, the Cu atom is in a square planar coordination. The molecules of 1 are linked through intermolecular N-H...N and N-H...O hydrogen bonds to form layers parallel to the ab plane. The molecules of 2 are linked through intermolecular C-H...Br hydrogen bonds to form a 3D network.     

Chlorine reaction with platinum triamine [Pt(N,N-DimeTm)PyCl3]Cl (N,N-DimeTm = (CH3)2N(CH2)3NH2). Crystal structure of [Pt(N,N-DimeTm)Cl2], [Pt(N,N-DimeTm(Py)Cl3]Cl · H2O and [Pt{(CH3)2N(CH2)2C(O)NH}(Py)Cl3]

Treatment of platinum(II) diamine [Pt(N,N-DimeTm)Cl₂] (I) with pyridine gave tetramine [Pt(N,N-DimeTm)Py₂]Cl₂ (II); by oxidation with chlorine this was converted to Pt(IV) triamine, [Pt“(N,N-DimeTm(Py)Cl₃]Cl (III) with a six-membered chelate ring. According to X-ray diffraction data, the reaction of complex II with chlorine is accompanied by removal of the pyridine molecule from the trans-position to the NH₂ group of N,N-dimethyltrimethylenediamine. The reaction of complex III with chlorine at 20°C afforded a mixture of compounds (IV) and the complex [Pt“(CH₃)₂N(CH₂)₂C(O)NH”(Py)Cl₃] (V) with an amidate six-membered metal ring, dimethylpropioamide, which was also isolated upon refluxing a mixture of IV in an aqueous solution. The UV/Vis and IR spectra of the obtained complexes were studied, and X-ray diffraction analysis of I, III, and V was performed. The crystals of I are triclinic, space group P $ \bar 1 $ ; a = 7.6526(4) Å, b = 11.5571(6) Å, c = 12.4432(7) Å, α = 113.85(1)°, β = 96.54(2)°, γ = 106.78(2)°; Z = 4; R _hkl = 0.051. The crystals of III are monoclinic, space group C2/c; a = 36.715(2) Å, b = 7.8179(4) Å, c = 29.721(16) Å, β = 127.80(1)°; Z = 16; R _hkl = 0.036. The crystals of V are monoclinic, space group P2₁/n; a = 7.0398(6) Å, b = 27.458(2) Å, c = 7.687(6) Å, β = 106.270(1)°; Z = 4; R _hkl = 0.052.     

Synthesis and X-ray diffraction study of cs3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] and Cs5[UO2(CH3COO)3]3[UO2(NCS)4(H2O)] · 2H2O

Cs₃[UO₂(CH₃COO)₃]₂[UO₂(CH₃COO)(NCS)₂(H₂O)] (I) and Cs₅[UO₂(CH₃COO)₃]₃[UO₂ (NCS)₄(H₂O)] · 2H₂O (II) have been synthesized via the reaction between uranyl acetate and cesium thiocyanate in aqueous solution. According to single-crystal X-ray diffraction data, both compounds crystallize in monoclinic system with the unit cell parameters a = 18.7036(5) Å, b = 16.7787(3) Å, c = 12.9636(3) Å, β = 92.532(1)°, space group C2/c, Z = 4, R = 0.0434 (I); and a = 21.7843(3) Å, b = 24.6436(5) Å, c = 13.1942(2) Å, β = 126.482(1)°, space group Cc, Z = 4, R = 0.0273 (II). Uranium-containing structural units of compound (I) are mononuclear [UO₂(CH₃COO)₃]^? and [UO₂(CH₃COO)(NCS)₂(H₂O)]^? moieties, which correspond to the AB ₃ ⁰¹ and AB⁰¹M ₃ ¹ crystallochemical groups (A = UO ₂ ²⁺ , B⁰¹ = CH₃COO^?, M¹ = NCS^? and H₂O). The structure of compound II is built of [UO₂(CH₃COO)₃]^? and [UO₂(NCS)₄(H₂O)]^2? complexes, which belong to the AB ₃ ⁰¹ and AM ₅ ¹ crystallochemical groups, respectively. Uranium-containing complexes in both structures are linked into a framework by hydrogen bonds and electrostatic interactions with cesium cations. The IR spectra of compounds I and II agree well with X-ray diffraction data.     

Copper(II) and lead(II) complexes based on 2,3,5,6-tetrakis(2-pyridyl)pyrazine as a polydentate ligand

The Cu(II) complexes [Cu(Tppz)(Dipic)] · 8H₂O (I) and [Pb₂(Tppz)Cl₄] _n (II), where Tppz, H2Dipic are 2,3,5,6-tetrakis(2-pyridyl)pyrazine, dipicolinic acid, respectively, have been synthesized and characterized by elemental analyses, IR, cyclic voltammetry, and electronic spectral studies. Solid state structures of both complexes have been determined by single crystal X-ray crystallography. An ORTEP drawing of two complexes shows that the coordination geometry around the metal center is a distorted octahedron. There are extensive conventional intermolecular O-H…O, N-H…O, and weaker C-H…O and C-H…Cl non-classical hydrogen bonds, which cause the stability of the crystal structure. Crystal data for I: monoclinic, space group: C2/c, a = 35.421(3), b = 8.422(6), c = 22.824(8) Å, β = 101.69(2)°, V = 6668(5) ų, Z = 8. Crystal data for II: triclinic, space group P \(\bar 1\) , a = 7.9534(4), b = 8.8682(5), c = 9.4245(5) Å, β = 95.086(2)°, V = 655.93(6) ų, Z = 2.     

Coordination compounds of cobalt(II) and cadmium(II) with 2-amino-4-methylpyrimidine: Synthesis, crystal structure, and luminescent properties

The coordination compounds [CoL₂Cl₂] (I) and [CdL₂(H₂O)₂(NO₃)₂] (II) have been synthesized by the reaction of CoCl₂ · 6H₂O and Cd(NO₃)₂ · 4H₂O with L = 2-amino-4-methylpyrimidine (Ampym, C₅H₇N₃), and their structures have been solved. The crystals of complex I are triclinic, space group $P\bar 1$ , a = 5.627(1) Å, b = 11.191(1) Å, c = 12.445(1) Å, α = 81.00(1)°, β = 77.21(1)°, γ = 76.18(1)°, V = 737.7(2) ų, ρ_calcd = 1.567 g/cm³, Z = 2. The crystals of complex II are monoclinic, space group P2₁/c, a = 10.390(1) Å, b = 11.982(1) Å, c = 7.624(1) Å, β = 102.61(1)°, V = 926.1(2) ų, ρ_calcd = 1.760 g/cm³, Z = 2. Discrete [CoL₂Cl₂] moieties are realized in the structure of complex I. The cobalt atom is tetrahedrally coordinated to the two nitrogen atoms of crystallographically nonequivalent ligands L and two chlorine atoms (Co(1)-N_avg, 2.051(4)Å; Co(1)-Cl(1), 2.241(1) Å; Co(1)-Cl(2), 2.263 Å; bond angles at the cobalt atom lie within a range of 102.1°–118.6°). The complexes are linked into supramolecular zigzag chains by N-H...N(Cl) hydrogen bonds. In the structure of complex II, the Cd²⁺ ion (at the inversion center) is coordinated in pairs to the nitrogen atoms of ligand L and the O(NO₃) and O(H₂O) oxygen atoms. The coordination of the Cd²⁺ ion is distorted octahedral (Cd(1)-N(1), 2.341Å; Cd(1)-O(1), 2.340(4) Å; Cd(1)-O(4), 2.327(3) Å; bond angles at the cadmium atom lie within a range of 79.1°–100.9°). N-H...N hydrogen bonds link the complexes into supramolecular chains. These chains are linked into a supramolecular framework by the O-H...O hydrogen bonds between water molecules and NO₃ groups.     

Silver complexes with 2-amino-4-methylpyrimidine: Synthesis, crystal structure, and luminescent properties

Reactions of AgReO₄ and AgCH₃SO₃ with L = 2-amino-4-methylpyrimidine (Ampym, C₅H₇N₃) in a ratio of 1: 2 in acetonitrile gave the complexes [AgL₂(ReO₄)] (I) and [AgL₂(CH₃SO₃)] (II). Their structures were determined. The crystals of complex I are monoclinic, space group C2/c, a = 5.985(1), b = 3.465(1), c = 19.071(1) Å, β = 96.52(1)°, V = 1527.0(3) ų, ρ_calcd = 2.507 g/cm³, Z = 4. The crystals of complex II are orthorhombic, space group Pbca, a = 14.784(1), b = 11.991(1), c = 17.711(1) Å, V = 3139.7(4) ų, ρ_calcd= 1.782 g/cm³, Z = 8. Structure I shows discrete cationic complexes [AgL₂]⁺. The silver atom is virtually linearly coordinated to two N atoms of crystallographically equivalent ligands L (Ag-N, 2.156(4) Å; the angle NAgN, 174.7(4)°). The complex cations are united into zigzag chains through the hydrogen bonds N-H...N. The resulting chains are linked by the hydrogen bonds N-H...O to uncoordinated perrhenate anions to form 2D supramolecular layers. In structure II, the Ag⁺ ion is coordinated by two crystallographically non-equivalent ligands L in a distorted linear fashion: Ag(1)-N(1), 2.166(7) Å;Ag(1)-N(4), 2.181(6) Å; the angle NAgN, 157.2(2)°. The anions CH₃SO₃ ^? are weakly linked to the Ag⁺ ions (Ag...O 2.72 Å) and are hydrogen-bonded to the complex cations [AgL₂]⁺, uniting them into supramolecular ribbons.     

Synthesis, structure, luminescence properties, quantum chemistry and cytotoxic effects of two vanadium(IV) complexes with polypyrazolylborates, HB(pz)3VO(acac) and HB(3,5-Me2pz)3VO(acac)·CH3CN (pz = pyrazole)

The reaction of VO(acac)₂ (acac = acetylacetonate) with NaHB(pz)₃ (pz = pyrazole) or NaHB(3,5-Me₂pz)₃ in methanol gave vanadium(IV) complexes HB(pz)₃VO(acac) (1) or HB(3,5-Me₂pz)₃VO(acac)·CH₃CN (2), respectively. The complexes 1 and 2 were characterized by elemental analysis, IR, UV-vis, NMR and X-ray diffraction crystallography methods. Complex 1 crystallizes in space group P2₁/c, a = 7.641(2) Å, b = 17.008(4) Å, c = 13.362(2) Å; β = 92.092(17)°, V = 1735.5(7) ų, Z = 4. Complex 2 crystallizes in space group P2₁/c, a = 17.410(13) Å, b = 8.076(16) Å, c = 19.300(13) Å; β = 101.75(5)°, V = 2657(6) ų, Z = 4. X-ray structure analyses have shown that the complexes 1 and 2 are monomeric with a similar coordination environment of the vanadium atom. Luminescence properties and cytotoxic effects of the complexes are discussed. On CBRH-7919 cells, the complexes 1 and 2 caused a slight stimulation of growth at low doses (1–10 μM) and a significant cytotoxic effect at higher doses (100–1000 μM). The electronic structure and the bonding characters of the two complexes were analyzed with ab initio calculations. Original Russian Text Copyright ? 2006 by Y. H. Xing, Z. Sun, W. Zou, J. Song, K. Aoki, and M. F. Ge __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No. 5, pp. 924–932, September–October, 2006.     

Synthesis and study of tetraamminecobalt hydrogen hexamolybdometalates(III)

Tetraamminecobalt hydrogen hexamolybdoferrate [Co(NH₃)₄] · H[FeMo₆O₁₈(OH)₆] · 6H₂O (I) and tetraamminecobalt hydrogen hexamolybdogallate(III) [Co(NH₃)₄] · H[GaMo₆O₁₈(OH)₆] · 6H₂O (II) were synthesized and studied by mass spectrometry, thermogravimetry, IR spectroscopy, and X-ray diffraction. Crystals of I and II are monoclinic; a = 16.21 Å, b = 5.43 Å, c = 12.32 Å, β = 119.63°, V = 1092.11 ų, ρ_calcd = 2.21 g/cm³, and Z = 1 for I; a = 16.24 Å, b = 5.59 Å, c = 12.29 Å, β = 119.79°, V = 1064.05 ų, ρ_calcd = 2.15 g/cm³, and Z = 1 for II. Compounds I and II were used as catalysts for soft oxidation of natural gas.