I. N. Polyakova

Complexes in the Ni2+-imidazole-RN(CH2COO−)2 systems. The crystal structures of tris(imidazole)iminodiacetatonickel(II) monohydrate, hexa(imidazole)nickel(II) bis(N-methyliminodiacetato)nickelate(II) hexahydrate, and tetra(aqua)bis(imidazole)nickel(II) bis(N-benzyliminodiacetato)nickelate(II)

Crystals of different compositions, namely, [Ni(Ida)(Im)3] ⋅ H2O (I), [Ni(Im)6][Ni(Mida)2] ⋅ 6H2O (II), and [Ni(Im)2(H2O)4][Ni(Bida)2] (III), have been precipitated from aqueous solutions of the Ni2+-Lig2−-Im systems, where Lig2− is Ida, Mida, and Bida, respectively. The crystal structures of I–III are determined by X-ray diffraction analysis (R = 0.0307, 0.0348, and 0.0302 for 3061, 4706, and 2882 reflections, respectively). Crystals I are built of monomeric mixed-ligand complexes and molecules of crystallization water, which are interlinked by hydrogen bonds into a three-dimensional framework. In II and III, the ligands Lig2− and Im form charged complexes separately. In II, the cationic and anionic layers of the complexes alternate along the c-axis. Numerous hydrogen bonds involving molecules of crystallization water link the layers into a three-dimensional framework. In III, the cationic and anionic complexes, which serve as proton donors and acceptors, respectively, are bound into layers parallel to the xy plane.

Crystal Structure of Calcium [Aqua(Nitrilotriacetatocobaltate(II)] Tetrahydrate, Ca[Co(Nta)(H2O)]2· 4H2O

Crystals of Ca[CoII(Nta)]2· 6H2O (I), where Nta3–is a nitrilotriacetate ion, were synthesized and studied using X-ray diffraction analysis. They were found to be monoclinic: a= 6.991(1), b= 10.031(1), c= 16.238(3) Å, β = 98.50(1)°, V= 1126.2(3) Å3, space group P21/n, Z= 2, R1= 0.0241, wR2= 0.0636, GOOF = 1.050 (for 3132 reflections with I> 2σ(I)). Structure Iis composed of {[Co(Nta)(H2O)]–}1∞anion chains united by Ca2+cations into a three-dimensional framework. The coordination polyhedra of Co and Ca atoms are distorted octahedra. The Co(II) atom environment includes atoms N(1), O(1), O(3), and O(5) of one Nta3–ligand, a carbonyl O(2) atom of the neighboring anion fragment, and an O(w1) atom of the water molecule. The shortest bond is formed by the Co atom with the bridging O(2) atom in trans-position relative to atom N(1). The Co–O(2) distance (2.029 Å) is noticeably shorter than the other bond lengths, Co–O(Nta) (2.069–2.103 Å), Co–O(w1), and Co–N(1) (2.155 and 2.177 Å, respectively). Cations Ca2+are located in the inversion centers and involve in their coordination atoms O(4), O(6), O(w2), and the oxygen atoms symmetrically bond to them and arranged at 2.271(1), 2.420(1), and 2.351(2) Å, respectively. The structural formula of the title compound is {Ca(H2O)2[Co(Nta)(H2O)]2}3∞· 2H2O.

Crystal structures of acid ethylenediaminetetraacetates [Cd(H2Edta)(H2O)] · 2H2O and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O

The crystal structures of [Cd(H2Edta)(H2O)] · 2H2O (I) and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O (II) are studied by X-ray diffraction [R1 = 0.0209 (0.0272), wR2 = 0.0571 (0.0730) for 2551 (4025) reflections with I > 2σ(I) in I (II), respectively]. Structure I contains mononuclear [Cd(H2Edta)(H2O)] complexes with the C2 symmetry, and structure II contains centrosymmetric trinuclear [Mn(H2O)4][Mn(HEdta)(H2O)]2 complexes. In I and II, the protonated ligands are hexadentate (2N + 4O), and the water molecule increases the coordination number of the metal atom to seven. The acid protons participate in short intermolecular hydrogen bonds, which are symmetric in II and asymmetric in I.

Crystal structure of strontium aqua(ethylenediaminetetraacetato)cobaltate(II) tetrahydrate Sr[CoEdta(H2O)] · 4H2O

The complex Sr[CoIIEdta] · 5H2O (I) (where Edta4− is the ethylenediaminetetraacetate ion) has been synthesized. The crystal structure of this compound is determined by X-ray diffraction. Crystals are monoclinic, a = 7.906(2) Å, b = 12.768(2) Å, c = 18.254(3) Å, β = 95.30(3)°, V = 1834.8 Å3, space group P21/n, Z = 4, and R = 0.036. The structure is built up of the binuclear complex fragments {Sr(H2O)3[CoEdta(H2O)]}, which consist of the anionic [CoEdta(H2O)]2− and cationic [Sr(H2O)3]2+ units linked by the Sr-O bonds into a three-dimensional framework. The coordination polyhedra of the Co and Sr atoms are mono-and bicapped trigonal prisms. The coordination sphere of the Co atom (the coordination number is equal to 6 + 1) involves six donor atoms (2N and 4O) of the Edta4− ligand and the Ow atom of water molecule. One of the Co-O distances (2.718 Å) is considerably longer than the other Co-Olig distances (2.092–2.190 Å) and the Co-Ow(1) distance (2.079 Å). The Sr coordination polyhedron (the coordination number is eight) contains three water molecules, three carbonyl O atoms of the three different anionic complexes, and two O atoms of one acetate group of the fourth anionic complex. The Sr-O distances fall in the range 2.535–2.674 Å. The structural formula of the compound is {Sr(H2O)3[CoEdta(H2O)]}3∞ · H2O.

Copper(II) complex compounds with 1-phenyl-3-methyl-4-azopyrazol-5-one derivatives. The crystal and molecular structure of Cu(C17H15N4O)2 · 0.222H2O

Seven new copper(II) complexes with 1-phenyl-3-methyl-4-azopyrazol-5-one were synthesized and isolated in the crystalline state. The crystal and molecular structure of the complex Cu(C17H15N4O)2 · 0.222H2O was studied by X-ray diffraction. The organic ligand is coordinated to copper in the anionic form in the bidentate chelating mode through the oxygen atom of the pyrazolone moiety and one nitrogen atom of the azo group. As a first approximation, the copper(II) coordination polyhedron (CP) is a tetrahedrally distorted square. The copper CP is completed to an extended tetragonal pyramid (4+1) by the Cu⋯N(1) contact (3.072 Å) with the pyrazole nitrogen of the neighboring molecule.

Structure of uranyl complexes with acetylenedicarboxylic acid, K(H5O2)[UO2(OOCC≡CCOO)2 · H2O] · 2H2O and Cs2[UO2(OOCC≡CCOO)2 · H2O] · 2H2O

Uranyl complexes with acetylenedicarboxylic acid, K(H5O2)[UO2L2H2O] · 2H2O (I) and Cs2[UO2L2H2O] · 2H2O (II), L2− = C4O42− were prepared for the first time. The composition and structure of the complexes were determined by X-ray diffraction. The crystal data are as follows: a = 16.254(12) Å, b = 13.508(8) Å, c = 7.683(6) Å, β = 90.91(7)°, space group C2/c, V = 1687(2) Å3 (I); a = 7.0745(10), b = 18.4246(10), c = 13.1383(10) Å, space group Abm2, V = 1712.5(3) Å3 (II). The structures of I and II are based on [UO2L2H2O]n2− anionic chains stretched along the [101] direction (I) or [010] direction (II). In I and II, the uranium coordination polyhedron is a pentagonal bipyramid in which the equatorial environment of the uranyl ions is formed by the oxygen atoms of the four L2− anions and the water molecule. The L2− anions in I and II are bidentate bridging ligands connecting two uranium atoms that are next to each other in the anionic chain; their coordination capacity is equal to 2. In I, the K+ and H5O2+ cations are outer-sphere species. The latter form hydrogen bonds combining the anionic chains shifted by translation b with respect to each other. The [UO2L2H2O]n2− chains in I are surrounded by the potassium and oxonium cations; in II, these are combined by hydrogen bonds into anionic layers between which Cs+ cations are arranged. The IR spectrum of compound II was measured and interpreted.

Crystal structure of neptunium(IV) N,N-diethyl dithiocarbamate Np[S2CN(C2H5)2]4

Crystal structure of Np[S2CN(C2H5)2]4 has been determined. The environment of the Np atom is formed by eight sulfur atoms. The coordination polyhedron of the Np atom is a dodecahedron. The Np-S bond lengths vary from 2.782(2) to 2.812(2) Å (average 2.795 Å). Two independent (H5C2)2NCS2− anions are characterized by different orientations of the diethylcarbamate fragments. A comparison of the geometric characteristics of the coordination polyhedra of the compounds An[S2CN(C2H5)2]4 (An = Th, Np) and Np(S2CN(C2H5)2)4][N(C2H5)4 shows that the average Np-S bond lengths in the coordination polyhedra decrease by the same value on going from Th4+ to Np4+ and from Np3+ to Np4+.

Structures of mixed-ligand Manganese(II) compounds [Mn(Heida)(Phen)]2 · 7H2O and [Mn2(Edta)(Phen)] · 4H2O

The crystal structures of [Mn(Heida)(Phen)]2 · 7H2O (I) and [Mn2(Edta)(Phen)] · 4H2O (II) are studied by X-ray diffraction [R1 = 0.0375 (0.0283) and wR2 = 0.0954 (0.0662) for 5449 (3176) observed reflections in I (II), respectively]. Structure I contains mononuclear mixed-ligand complexes [Mn(Heida)(Phen)] and [Mn(Heida)(Phen)(H2O)]. In structure II, the [Mn(Edta)]2− anionic complexes and the [Mn(Phen)(H2O)2]2+ cationic complexes are linked by the bridging carboxyl groups into the tetramers with C2 symmetry. In both compounds, two independent Mn atoms have different coordination numbers (6 and 7).

Crystal structure of dibarium (Ethylenediaminetetraacetato)cuprate(II) diperchlorate hexahydrate, Ba2[Cu(Edta)](ClO4)2 ⋅ 6H2O

Compound Ba2[Cu(Edta)](ClO4)2 ⋅ 6H2O is synthesized and its crystal structure is determined [R = 0.0500 for 4439 reflections with I > 2σ(I)]. The structure consists of the [Cu(Edta)]2− anionic complexes, hydrated barium cations, Cl4− anions, and molecules of crystallization water, which are interlinked into a framework. The hexadentate Edta4− ligand coordinates the Cu atom forming the polyhedron in a shape of a tetragonal bipyramid, which is asymmetrically stretched along the OR-Cu-OR, axis (Cu-O, 2.262 and 2.532 Å). The mean lengths of the equatorial Cu-N and Cu-O bonds are 2.011 and 1.952 Å, respectively. The anionic complex is bound to six Ba atoms. Two independent Ba atoms have different environments; their coordination numbers are nine and ten. The Ba-O distances lie in the range 2.669–3.136 Å. Layers of Ba atoms parallel to the x0z plane are distinguished in the structure.

1,3-Diamino-2-Hydroxypropane- N , N , N ′, N ′-Tetraacetic Acid: Crystal and Molecular Structures

The synthesis, IR spectroscopic study, and X-ray diffraction analysis (CIF file CCDC no. 1574078) are carried out for 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (I). The structural units of a crystal of compound I are (H4.5HPdta)0.5– anions, (H5.5HPdta)0.5+ cations, and molecules of water of crystallization joined by a branched network of hydrogen bonds: strong intermolecular O–H…O and intramolecular N–H…O bonds.