Crystal structure of [PrCl3(15-crown-5)] prepared via electrocrystallization

[PrCl₃(15-crown-5)] was synthesized by electrocrystallization using a 11 metal to crown molar ratio. The complex crystallizes in the centricP2₁/c space group witha=8.191(4)Å,b=14.245(9)Å,c=14.226(6)Å,=104.69(6)°, andD _calc=1.93 g/cm³ forZ=4 (20°C). A finalR value of 0.070 was obtained via least-squares refinement using 2356 independent observed [F ₀5(F _o)] reflections. The Pr ion is eight-coordinate with three chloride ions and the five oxygens of the crown ether directly coordinated.     

Synthesis and X-ray crystallographic characterization of [Cd(NO3)2(15-Crown-5)] and [Cd(NO3)2(18-Crown-6)]

Reaction of 15-crown-5 or 18-crown-6 in 3:1 (v/v) CH₃CN:CH₃OH with Cd(NO₃)₂·4H₂O followed by slow evaporation produces [Cd(NO₃)₂(15-crown-5)] or [Cd(NO₃)₂(18-crown-6)]. Crystals of [Cd(NO₃)₂(15-crown-5)] are orthorhombic with space group Pbca and cell parameters a = 13.562(5), b = 15.941(9), and c = 15.011(7) Å at 295 K. [Cd(NO₃)₂(18-crown-6)] crystallizes in the monoclinic space group C2/c with a = 11.235(2), b = 11.196(5), c = 15.385(3) Å, and = 99.89(2)° at 295 K. The metal center in [Cd(NO₃)₂(15-crown-5)] rests atop the macrocyclic donor array with two cis-bound nitrate anions and adopts a distorted tricapped trigonal prismatic geometry. [Cd(NO₃)₂(18-crown-6)] resides on an equatorial two-fold rotation axis with Cd²⁺ coordinated in the 18-crown-6 cavity and the nitrate anions oriented in twisted trans positions.     

Structure of the [5S,15S] isomer of the macrocyclic complex, [La(NCS)3(C24H30N6)]

The crystal and molecular structure of the [5S,15S] isomer of the [LaL(NCS)₃] complex (L=C₂₆H₃₀N₆) was determined by single crystal X-ray diffraction analysis. The compound crystallizes in the orthorhombic space group P2₁2₁2₁ witha=13.647(4),b=19.504(4),c=11.606(4)Å. The 9-coordinate La(III) is bound to the N atoms of three monodentate isothiocyanates and to the six N atoms of the macrocycle ligand L, which has an 18-membered, six-nitrogen donor cavity and two peripheral –CH₃ substituents.     

Synthesis and crystal structures of nitratocobaltates Na2[Co(NO3)4], K2[Co(NO3)4], and Ag[Co(NO3)3] and potassium nitratonickelate K2[Ni(NO3)4]

The cobalt(II) and nickel(II) nitrate complexes with an island structure (Na₂[Co(NO₃)₄] (I) and K₂[Co(NO₃)₄] (II)] and a chain structure [Ag[Co(NO₃)₃] (III) and K₂[Ni(NO₃)₄] (IV)] are synthesized and investigated using X-ray diffraction. In the anionic complex [Co(NO₃)₄]^2? of the crystal structure of compound I, the Co coordination polyhedron is a twisted tetragonal prism formed by the O atoms of four asymmetric bidentate nitrate groups. In the anion [Co(NO₃)₄]^2? of the crystal structure of compound II, one of the four NO₃ groups is monodentate and the other NO₃ groups are bidentate (the coordination number of the cobalt atom is equal to seven, and the cobalt coordination polyhedron is a monocapped trigonal prism). The crystal structures of compounds III and IV contain infinite chains of the compositions [Co(NO₃)₂(NO₃)_2/2]^? and [Ni(NO₃)₃(NO₃)_2/2]^2?, respectively. In the crystal structure of compound III, seven oxygen atoms of one monodentate and three bidentate nitrate groups form a dodecahedron with an unoccupied vertex of the A type around the Co atom. In the crystal structure of compound IV, the octahedral polyhedron of the Ni atom is formed by five nitrate groups, one of which is terminal bidentate. The data on the structure of Co(II) coordination polyhedra in the known nitratocobaltates are generalized.     

Coordination of Schiff bases derived from pyrrole-2-carboxaldehyde and triamines to copper(II) and nickel(II) ions. Crystal structures of [Cu(C15H20N5)]NO3 and [Ni(C15H20N5)]ClO4

The Schiffbases 1,9-bis(2-pyrrolyl)-2,5,8-triazanona-1,8-diene (H₂L¹), 1,10-bis(2-pyrrolyl)-2,5,9-triazaundeca-l,9-diene (H₂L²), and 1,11-bis(2-pyrrolyl)-6-methyl-2,6,10-triazaundeca-l,10-diene (H₂L⁴) react with copper(II) nitrate or nickel(II) perchlorate in the presence of triethylamine to give new complexes [Cu(HL^1,2,4)]NO₃ and [Ni(HL^1,2,4)]ClO₄. The crystal structures of [Cu(HL²)]NO₃ and [Ni(HL²)]CIO₄ have been determined from single crystal diffractometer data and refined to finalR factors of 5.09 and 5.3%, respectively. Crystallographic data: [Cu(HL²)]NO₃: monoclinic,P2₁/c,a=10.036(2),b=14.500(2),c=13.317(2) Å,=108.14(1)°,Z=4, andd _c =11.427 Mg m^–3; [Ni(HL²)]ClO₄: monoclinic,P2₁/n,a=10.578(3),b=13.953(3),c=12.394(4) Å,=93.78(2)°,Z=4, andd _c =1.549 Mg m^–3. In both the structures the potentially pentadentate ligand (HL²)^– acts as a tetradentate one leaving one pyrrole group uncoordinated. Interesting is the metal dependent sequence of the three chelate rings. While the Ni (II) ion coordinates the (HL²)^– ligand to form a 5-5-6-membered ring system, the ring arrangement in the copper complex is of the 5-6-5 type.     

Molecular and crystal structures of halopentaamminerhodium-(III) complexes, [Rh(NH3)5Cl]Cl2 and [Rh(NH3)5Br]Br2

The crystal and molecular structures of the title compounds have been determined by three-dimensional single-crystal X-ray techniques. All crystallographic details are fully reported. The major chemical conclusion for the pair, [Rh(NH₃)₅Cl]Cl₂ and [Rh(NH₃)Br]Br₂, is that neither Cl nor Br exert a static intramoleculartrans effect. Furthermore, the two halogens have the same static electronic structural effect on the [Rh^III(NH₃)₅] fragment. The conclusions shed much light on spectroscopic, thermodynamic and kinetic data of other compounds.Work supported in part by NSF-traineeship (E.A.H.).The term trans effect will be employed to refer to static and kinetic behavior-the distinction will be apparent from the context of the discussion.     

Silver(I) complexes of 6-methyl-2-pyridinecarboxylic acid: the crystal structure of [Ag(MeC5H3NCOO)(MeC5H3NCOOH)]

Silver(I) complexes of 6-methyl-2-pyridinecarboxylic acid (HL) have been prepared, and the crystal structure of [Ag(L)(LH)] has been determined from X-ray diffraction data. This complex crystallizes in the monoclinic space group P2₁/n, with a = 13.4055(13), b = 7.1012(7), c = 15.588(2) Å, = 112.779(2)°, and Z = 4. Anionic [AgL₂]^– units are linked together by protons in approximately symmetrical linear O—H—O hydrogen bonds involving uncoordinated carboxylate oxygen atoms, to give polymeric chains. The most significant intermolecular interaction between adjacent parallel chains is offset ring stacking of pairs of aromatic rings with a perpendicular distance of 3.27 Å. The Ag coordination geometry is highly distorted tetrahedral, from two pyridine N atoms and two carboxylate O atoms, each ligand forming a five-membered chelate ring.     

Structural studies of Mo(VI) coordination chemistry crystal and molecular structure of trispotassium [cis-trioxo(nitrilotriacetato)molybdate(VI)] monohydrate

The crystal structure of trispotassium [cis-trioxo(nitrilotriacetato)molybdate (VI)] monohydrate, C₆H₈K₃MoNO₁₀, has been determined. The crystals are monoclinic, space groupP2₁/c,a = 9.700(4),b = 19.628(6),c = 7.608(2) Å, = 110.58(4) ° andZ = 4. X-ray data were collected by counter methods using MoK. radiation, and least-squares refinement led toR = 0.055 for the 2234 independent reflections for which ¦F ₀¦² > (¦F ₀¦²). The anion contains acis-trioxo metal system, while the ligand coordinates as a tridentate through its nitrogen atom and two of the three carboxylate oxygen atoms, the Mo atom being in a distorted octahedral environment. The two glycinato rings involved in the coordination are mutuallycis. The mean Mo-O (terminal) bond length is 1.74 Å and the lengths of the metal-ligand bonds are Mo-O 2.18, 2,25 Å; Mo-N 2.39 Å.     

Synthesis and crystal structure of catena-poly[aqua(cis-syn-cis-dicyclohexyl-18-crown-6) tetra(thiocyanato)barium(II) platinum(II)]: [BaPt(NCS)4(C20H36O6)(H2O)] n

An organic–inorganic hybrid polymeric complex, [BaPt(NCS)₄(C₂₀H₃₆O₆)(H₂O)] _n or [[Ba(DC18C6-A)(H₂O)][Pt(SCN)₄]] _n (1) (DC18C6-A = cis-syn-cis-dicyclohexyl-18-crown-6) has been synthesized by the reaction of cis-syn-cis-dicyclohexyl-18-crown-6 with Ba(SCN)₂, BaCO₃ and H₂PtCl₄, and characterized by elementary analysis, FT-IR spectra and X-ray single-crystal diffraction. It crystallizes as monoclinic, space group P 2₁/n with crystallographic data: a = 14.275(6) ?, b = 13.165(5) ?, c = 18.971(8) ?, β = 106.294(6)°, V = 3422(2) ?³, Z = 4, D _calcd = 1.854 g/cm³, F(000) = 1856, R ₁ = 0.0491, wR ₂ = 0.0709. The asymmetric unit of complex 1 contains one [Ba(DC18C6-A)(H₂O)]²⁺ complex cation and one [Pt(SCN)₄]²⁻ complex anion, which are assembled into an infinite polymeric chain via the bridging SCN groups. The coordinated water molecule gives two different intrachain and interchain hydrogen bonds.     

Synthesis and the crystal structure of aqua-dioxo-nitrato-(2,2′,6′,2″-terpyridine)-neptunium(V) [NpO2(NO3)(terpy)(H2O)]

The crystal structure of the [NpO₂(NO₃)(Terpy)(H₂O)] complex between pentavalent neptunium and 2,2′,6′,2″-terpyridine is determined. The crystal data are as follows: a = 11.130(3) Å, b = 7.916(2) Å, c = 18.324(5) Å, β = 100.873(6)°, V = 1585.5(8) ų, Z = 4, space group is P2₁/n, R = 0.044, and wR(F ²) = 0.092. The coordination polyhedron of the Np atom is a pentagonal bipyramid whose equatorial plane includes three nitrogen atoms of the Terpy molecule and two oxygen atoms of the nitrate ion and the water molecule.     

Persistence of layer motifs in the crystal structures of [1,4-bis-(2-methoxy-2-carbonylethyl)piperazinium (2’)] chloride and [1,4-bis-(2-amidoethyl)piperazinium (2’)] perchlorate

Two structures of the closely related piperazinium salts, [1,4-bis-(2-methoxy-2-carbonylethyl)piperazinium (2+)] chloride (1) and [1,4-bis-(2-amidoethyl)piperazinium (2+)] perchlorate (2) reveal the persistence of a layer structure, interspersed with anions, held in place by N–H···Cl, C–H···O and C–H···Cl interactions in the case of 1, and N–H···O and C–H···O interactions in the case of 2. Compound 1 crystallizes in the triclinic space group P-1 with a=6.7667(6) ?, b = 6.9467(6) ?, c=9.3880(18) ?, α=105.845(9)°, β=99.896(16)°, γ=103.600(9)°, and Z=1. Compound 2 crystallizes in the monoclinic space group P2₁/c with a = 9.0930(8) ?, b=10.0525(11) ? c=10.2104(13) ?, β=114.279(9)°, and Z=2.     

Structural studies of Mo(VI) coordination chemistry crystal and molecular structure of ammonium [cis-dioxo(uramil-N,N-diacetato) molybdate(VI)] monohydrate

The crystal structure of ammonium [cis-dioxo(uramil-N, N-diacetato) molybdate(VI] monohydrate, C₈H₁₂MoN₄O₁₀, has been determined. The crystals are monoclinic: space groupP2₁/c,a = 6.744(3),b = 18.07(1),c = 11.500(9) Å, = 102.01(5) °,Z = 4. X-ray data were collected by counter methods using MoK radiation, and least-squares refinement led toR = 0.048 for the 1601 independent reflections for which ¦F ₀ ¦² > 3(¦F ¦²). The anion contains acis-dioxo metal system while the ligand coordinates as a tetradentate through the nitrogen and two oxygen atoms of theN-diacetate group and a carbonyl oxygen atom of the uramil skeleton. Metal ligand bondstrans to the terminal oxygen atoms are significantly lengthened. The pyrimidine ring of the ligand having lost a proton from the C₅ atom is planar and is also coplanar with the metal dioxo group.     

Polymeric and mixed carboxylate compounds: Crystal structures of [Zn(tiglate)2]x and [Zn2(tiglate)3(crotonate)]x

The crystal structures of [Zn(O₂CC(CH₃)CHCH₃)₂]_x and [Zn₂(O₂CC(CH₃)CHCH₃)₃-(O₂CCHCHCH₃)]_x have been determined by single crystal X-ray diffraction. Both structures consist of chain polymers, in which pairs of zinc atoms are bridged alternately by three syn-syn carboxylates and by one syn-anti carboxylate. In the mixed carboxylate structure, the crotonate takes up preferentially the syn-anti bridge position. Vibrational and elemental analysis data indicate that the spontaneous solid-state reaction of zinc tiglate in air, accelerated for the tiglate and observable also for the mixed carboxylate compound by -ray or X-ray irradiation, gives an oxocentered tetranuclear complex [Zn₄O(O₂CR)₆] rather than a polymerization through cross-linking of the unsaturated carboxylates.     

Synthesis and crystal structure of a mixed-ligand lanthanum complex of phenanthroline H-bonded with benzo-15-crown-5

A mixed ligand lanthanum complex H-bonded with a crown ether benzo-15-crown-5 (B15C5), [La(NO₃)₃(H₂O)₂phen]B15C5 (phen = phenanthroline), was synthesized and characterized by elemental analysis, infrared spectrum, and X-ray crystal structure analysis. The crystals of the title compound are monoclinic, P2₁, with a = 18.879(6) Å, b = 20.110(5) Å, c = 19.358(4) Å, V = 6623.4 ų, = 115.68(3)°, Z = 8, D _calc = 1.623 g/cm³. In this complex, two nitrogen atoms from phen and eight oxygen atoms, six from NO₃ ^– and two from H₂O, coordinate to La(III), forming a 10-coordination structural unit. The two H₂O molecules are located in opposite directions of the unit, each H₂O is H-bonded with two O atoms of the B15C5, and each B15C5 molecule is H-bonded with two H₂O molecules on opposite sides, thus an infinite supramolecular chain forms. The title compound has a layered structure, and in each unit cell there exists one 3D channel.     

Molecular and crystal structures of the product of the reaction between tetrafluoroborate tris[triphenylphosphinegold(I)]oxonium and calix[4]arene

The molecular and crystal structures of a complex salt in which the cation is tris[triphenylphosphinegold(I)]oxonium and the anion is deprotonated calix[4]arene are determined. The tris[triphenylphosphine-gold(I)]oxonium cation forms a centrosymmetric, doubly charged, hexanuclear dimer. The oxonium oxygen atoms are characterized by a nonplanar bond configuration: the Au-O-Au bond angles vary in the range 92.2(2)°–101.8(2)° due to aurophilic interactions (Au?Au) occurring at distances in the range 2.9650(4)–3.1836(4) Å. The monomers are joined into dimers via pairs of Au?Au interactions at a distance of 3.1880(5) Å. The anion adopts a cone conformation. The deprotonated oxygen atom of the anion is involved in the formation of two hydrogen bonds as a proton acceptor. In the crystal, two anions and one cation form a cluster in which the large-sized dimer cation is capped by the two calix[4]arene anions on opposite sides: { A-K-A}. In turn, these clusters form zigzag chains due to stacking interactions involving one of the benzene rings.     

Synthesis and crystal structures of lithium polyphosphates, LiPO3, Li4H(PO3)5, and LiMn(PO3)3

Polyphosphates of the compositions LiPO₃, Li₄H(PO₃)₅, and LiMn(PO₃)₃ were prepared by the reactions of Li₂CO₃ and MnO₂ with melts of polyphosphoric acids at 240–350°C, and their crystal structures were established. The unit-cell parameters are a = 13.074 Å, b = 5.4068 Å, c = 16.452 Å, β = 99.00°, sp. gr. P2/n; a = 6.6434 Å, b = 7.253 Å, c = 11.399 Å, α = 72.60°, β = 83.36°, γ = 85.32°, sp. gr.; $P\bar 1$ ; a = 8.364 Å, b = 8.561 Å, c = 8.6600 Å, sp. gr. P2₁2₁2₁, respectively. The influence of cations on the structures of the compounds is discussed.     

The Crystal Structure of [La(NO3)6{Cu(2,2′-bipy)2}2][La(NO3)6Cu(2,2′-bipy)2]CH3CN with the Most Profuse Modes of Nitrate Coordination

The title compound [La(NO₃)₆{Cu(2,2′-bipy)₂}₂][La(NO₃)₆Cu(2,2′-bipy)₂] CH₃CN was synthesized, the crystal and molecular structures were determined at room temperature. The complex formed monoclinic crystals, space group P21/n (No.14), a = 10.354 (3) A, b = 23.440 (9) A, c = 32.817 (9) A, b = 90.39 (2)°, Z = 4. The crystal structure consisted of a discrete [La(NO₃)₆{Cu(2,2′-bipy)₂}₂]⁺ cation and [La(NO₃)₆Cu(2,2′-bipy)₂]^- anion and a non-coordinated CH₃CN molecule. Each La(III) ion was 12-coordinate with twelve oxygen atoms from six chelating nitrate ligands. There were four modes of nitrate coordination and the coordination geometry of all three copper ions was different in the crystal structure.