Syntheses and Crystal Structures of a Series of Manganese-Lanthanide-Sodium 12-Metallacrown-4 Dimers

A series of heterotrimetallic manganese-lanthanide-sodium dimer metallacrowns has been synthesized and characterized by single-crystal X-ray analysis: {LnNa[12-MC_{Mn(III)N(shi)}-4]}₂(iph)₄, where Ln^III?=?La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Tm (12), Yb (13), Lu (14), and Y (15); MC is metallacrown; shi^3? is salicylhydroximate; and iph^2? is isophthalate. The manganese(III) ions and shi^3? ligands generate the 12-MC-4 framework with one Ln^III and Na⁺ ion bound to each [12-MC_{Mn(III)N(shi)}-4] on opposite sides of the central MC cavity. The carboxylate groups of the isophthalate ligands bridge between the central Ln^III ion and each ring Mn^III ion, and the meta-arrangement of the carboxylate groups joins two LnNa[12-MC_{Mn(III)N(shi)}-4] units together to form the dimer through the Ln^III ions, which reside on the interior of the molecule. The identity of the central Ln^III ion slightly impacts the size the [12-MC_{Mn(III)N(shi)}-4] framework. As the crystal radius of the Ln^III ion increases from Lu^III (1.02 Å) to La^III (1.19 Å), the 12-MC-4 framework expands to accommodate the larger Ln^III ion as the MC cavity increases in size (0.53 Å for Lu^III to 0.58 Å for La^III) and the average cross cavity Mn^III-Mn^III and oxime oxygen-oxime oxygen distances also increase (Mn^III-Mn^III distances: 6.48 Å for Lu^III to 6.52 Å for La^III; O_oxime-O_oxime distances: 3.66 Å for Lu^III to 3.75 Å for La^III). In addition, the larger Ln^III ions reside further from the MC cavity as indicated by the Ln^III-oxime oxygen mean plane (O_oxMP) distance. The Ln^III-O_oxMP distance steadily decreases from La^III (1.7527(12) Å) to Lu^III (1.5575(15) Å).

Graphic Abstract

The complex {LaNa[12-MC_{Mn(III)N(shi)}-4]}₂(iph)₄(DMF)₆(H₂O)₂ is a dimer of [12-MC-4] molecules linked by four isophthalate anions

     

3-(benzo[d]thiazol-2-YL)phenol and 4-(benzo[d]thiazol-2-YL)phenol: Crystal Structure Determination,DFT Calculations and Visualizing Intermolecular Interactions Using Hirshfeld Surface Analysis

This article describes the synthesis and X-ray crystal structure analysis of 3-(benzo[d]thiazol-2-yl) phenol (I) and 4-(benzo[d]thiazol-2-yl)phenol (II), crystallized in centrosymmetric triclinic and orthorhombic space groups respectively. The packing in the unit cell of these two positional isomers are different resulting difference in various types of intermolecular interactions (C-H…S, O-H…O_w and O-H…N) connect the molecules into 2D frameworks. Due to presence of lattice water in compound (I), H-bonding interactions are strong and melting point of (I) is comparatively higher than (II). The DFT optimized molecular geometries in (I) and (II) agree closely with those obtained from crystallographic studies.     

Synthesis and structure of the first water-soluble chiral monomeric MnIV complex: [Δ-MnIV(biguanide)3] (ClO4)4·H2O

The reaction of KMnO₄ with alkaline biguanide sulfate solution, followed by acidification of the resulting stable filtrate with concentrated HClO₄, led to the title complex, 1. The crystal structure of the [Δ-Mn^IV(bigH)₃](ClO₄)₄·H₂O (1, bigH: biguanide, C₂H₇N₅) has a tetragonal chiral P4 ₁ 2 ₁ 2 space group with a = b = 11.416(3) ?, c = 20.742(7) ?, Z = 4. The complex consists of one chiral [Δ-Mn^IV(bigH)₃] tetracation, four ClO₄ ⁻ anions, and one water molecule. In the tetracation, six N atoms from three neutral biguanide chelate coordinate to the Mn^IV cation, forming an octahedron with Δ-optical activity. The [Δ-Mn^IV(bigH)₃] tetracation interconnects each other by numerous hydrogen bonds with N–H···O and O–H···O between biguanide moieties of the [Δ-Mn^IV(bigH)₃] tetracations and counter-anions as well as water molecules, to construct a three-dimensional network.     

Structures of Three Chalcones Derived from 6-Methoxy-2-naphthaldehyde

Abstract  In the molecular structures of three new structurally related chalcone derivatives, namely (2E)-1-(2-hydroxyphenyl)-3-(6-methoxy-2-naphthyl)prop-2-en-1-one, C₂₀H₁₆O₃, I, (2E)-1-(2-chloropyridin-4-yl)-3-(6-methoxy-2-naphthyl)prop-2-en-1-one, C₁₉H₁₄ClNO₂, II, and (2E)-3-(6-methoxy-2-naphthyl)-1-pyridin-4-ylprop-2-en-1-one, III, C₁₉H₁₅NO₂, the configuration of the keto group is syn with respect to the olefinic double bond. In all three structures the molecules pack with weak intermolecular C–H···O interactions utilizing both the methoxy and keto oxygen’s in I, the methoxy oxygen in II and the keto oxygen in III. These interactions link the molecules into chains diagonally along the (011) plane of the unit cell in I and III and along the (010) plane in II. The dihedral angle between the phenyl and 2-napthyl rings in I is 31.7(3)°. In II and III the dihedral angle between the pyridyl and 2-naphthyl rings is 14.4(9)° and 1.8(9)°, respectively. C–H···O hydrogen bonding interactions influence these twist angles of these rings in I–III while weak π–π stacking interactions between naphthyl rings in I and III and also between pyridyl and naphthyl rings in II help stabilize crystal packing. [I: P2 ₁ /c, a = 7.6635(4) ?, b = 11.8047(6) ?, c = 16.7584(7) ?, β = 99.271(5)°, V = 1496.25(13) ?³; II: Pbca, a = 14.1424(4) ?, b = 6.0957(2) ?, c = 33.1458(11) ?, V = 2857.43(16) ?³; III: P2 ₁ /c, a = 11.5155(4) ?, b = 6.0020(2) ?, c = 22.4645(8) ?, β = 103.002(4)°, V = 1512.85(9) ?³]. Index Abstract  Crystal structures from three Chalcones derived from 6-methoxy-2-naphthaldehyde are reported and their geometric and packing parameters described.     

X-ray crystallographic determination of the structure and conformation of new metabolites from microbial hydroxylation by Absidia blakesleeana ATCC 10148

The crystal structure and conformation of 10R-hydroxy-1,4,4-trimethyltricyclo[5.4.0.0^3.5]undec-7-en-9-one (II) and 10S-hydroxy-1,4,4-trimethyltricyclo[5.4.0.0^3.5]undec-7-en-9-one (III) have been determined by X-ray diffraction. In both cases the crystals were monoclinic, P2₁,a=12.907 (4),b=7.484(3),c=14.179(4) Å,=110.65 (3)°,Z=4, (II);a=16.351 (5),b=7.468 (3),c=20.917 (6) Å,=91.83 (4)°,Z=8 (III). The structure was solved by direct methods, and refined to anR _w value of 0.034 for 2483 (II) and 0.053 for 3810 (III) independent reflections, withI3.0(I). There were two crystallographically independent molecules in the case ofII and four in the case ofIII. In all independent forms of both compounds the ring substituted by a carbonyl group had the distorted³E sofa conformation; whereas the second one possessed the slightly deformed^7.10B boat conformation. The crystal structures ofII andIII are stabilized by two and four intermolecular hydrogen bonds, respectively.The nomenclature of IUPAC was applied for the names of compounds, However, for simplicity, numbering of atoms was according to Figs, 1a and 1b.     

Synthesis, Crystal Structure and Magnetic Property of a Cyano-Bridged Two-Dimensional Heterometallic Assembly [Mn(salen)]2[Fe(CN)5NO]·2H2O

Abstract  

A cyano-bridged bimetallic assembly, [Mn^III(salen)]₂[Fe^II(CN)₅NO]·2H₂O [salen = N,N′-1,2-ethylenebis(salicylideneiminato)dianion], has been prepared and characterized structurally and magnetically. It crystallizes in the tetragonal space group P4/ncc with a = b = 14.813(2) ?, c = 17.093(5) ?, V = 3750.6(13) ?³, Z = 4. In this complex, each [Fe(CN)₅NO]²⁻ unit connects four [Mn(salen)]⁺ units with its four co-planar cyanide groups, and each [Mn(salen)]⁺ unit is linked to two [Fe(CN)₅NO]²⁻ ions in trans-form, which results in a two-dimensional (2-D) network consisting of pillow-like octanuclear [–Fe^II–CN–Mn^III–NC–]₄ units with dimensions: Fe–C = 1.943(3) ?, C≡N– = 1.139(4) ?, Mn–N = 2.326(3) ?, Fe–C≡N = 178.0(3)°, Mn–N≡C = 161.7(3)°. The NO group of [Fe(CN)₅NO]²⁻ remains monodentate and the bond angle of Fe–N–O is linear (180.0°). The variable temperature magnetic susceptibilities, measured in the 1.8–300 K range, show a weak Mn^III···Mn^III antiferromagnetic interaction through the diamagnetic –NC–Fe^II–CN– bridges.     

Crystal Structure Analysis of {[μ‐N,N′‐Bis(salicylidene)‐2,2′‐dimethyl‐1,3‐propanediaminato](dimethylformamide) zinc(II)}diiodomercury(II)

The title compound, a hetero‐dinuclear complex with Zn^II and Hg^II ions, forms crystals which belong to the monoclinic system, space group P2₁/n, with unit cell dimensions a = 11.2217(12), b = 17.7493(11), c = 13.9293(13) Å, β = 94.830(3)°, V = 2764.5(4) ų. The cell contains four molecules. The Zn…Hg distance is 3.5362(15) Å.     

Molecular and crystal structures of dibenzenehemiporphyrazine complexes with dimethylformamide

The crystal structures of the 1: 1 and 1: 2 complexes between dibenzenehemiporphyrazine (I) and dimethylformamide (compounds II and III, respectively) are determined by X-ray diffraction. In both compounds, the macrocycle has a saddlelike shape. In III, the conformation of the macrocycle approximates the C _2v symmetry, which agrees closely with the results of quantum-chemical calculations for isolated molecule I and complex II. The ring conformation in crystal II is distorted under the effect of intermolecular interactions, as is evidenced by short intermolecular contacts. The complexes are stabilized by intermolecular N-H?O and C-H?O hydrogen bonds between the hydrogen atoms situated inside the cavity of the macrocycle and the oxygen atoms of the dimethylformamide molecules.     

Synthesis and characterization of copper(II) hexaazamacrotetracyclic complex with thiocynate ligand

A mononuclear complex [Cu(L)(NCS)](ClO₄) (1) (L = 1,3,10,12,16,19-hexaazatetracyclo [17,3,1, 1^12.16,0^4.9]tetracosane) has been synthesized and structurally characterized by X-ray crystal structure analysis. The crystals are monoclinic P2₁2₁2₁ with a = 9.596(1), b = 11.285(1), c = 22.446(2) Å, V = 2430.7(3) ų, Z = 4. The copper atom is coordinated by two secondary and two tertiary amines of the macrocycle and one nitrogen atom of the thiocynate ligand in a distorted square-pyramidal geometry. The cyclic voltammogram of 1 exhibits two waves of a one-electron transfer corresponding to Cu^II/Cu^III and Cu^II/Cu^I processes.     

Synthesis and Characterization of Nickel(II) Complex of 3,14-Dimethyl-2,6,13,17-Tetraazatricyclo[14,4,01.18,07.12]Docosane Containing Pyrazine-2-Carboxylate Ligand

Abstract  

The reaction of [Ni(L)]Cl₂·2H₂O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane) with pyrazine-2-carboxylic acid (H-pyc) yields mononuclear nickel(II) complex, [Ni(L)(pyc)₂]·2H₂O (1). This complex has been characterized by X-ray crystallography, electronic absorption and cyclic voltammetry. The crystal structure of 1 exhibits a distorted octahedral geometry with four nitrogen atoms of the macrocycle and two pyrazine-2-carboxylate ligands. It crystallizes in the triclinic system P-1 with a = 9.6643(17), b = 10.116(3), c = 16.99(4) ?, V = 1633(3) ?³, Z = 2. Electronic spectrum of 1 also reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes two waves of a one-electron transfer corresponding to Ni^II/Ni^III and Ni^II/Ni^I processes.     

Synthesis,spectroscopic characterization and crystal structure of 5-bromo-1-(2-cyano-pyridin-4-yl)-1H-indazole-3-carboxylic acid diethylamide

The title compound 5-bromo-1-(2-cyano-pyridin-4-yl)-1H-indazole-3-carboxylic acid diethylamide, C₁₈H₁₆BrN₅O, is prepared from 5-bromoindazole-3-carboxylic acid methylester. N ¹-arylation is carried out with 4-chloro-2-cyanopyridine and the resulting product is converted to diethylamide by reacting with thionyl chloride and diethylamine. The structure is identified from its FT-IR, ¹H NMR, ¹³C NMR spectroscopy, elemental analysis data and unambiguously confirmed by single crystal X-ray diffraction studies. There are two symmetry independent molecules in the asymmetric unit with no significant differences in bond lengths and angles. The title compound crystallizes in the triclinic system, space group \(P\bar 1\) , with a = 11.2330(2); b = 11.6130(2); c = 15.4710(3) Å, α = 92.515(1)°; β = 109.956(1)°; γ = 107.199(1)°; V = 1788.45(6)ų and z = 4. An intramolecular C-H…N hydrogen bond forms an S(6) ring motif in one of the unique molecules. In the crystal, two molecules are linked about a center of inversion by C-H…O hydrogen bonded dimers generating an R ₂ ² (16) ring motif. The crystal packing is stabilized by C-H…N, C-H…O hydrogen bonds and π…π stacking interactions.     

Structures of three halo(tetramethylethylenediamine)copper(I) complexes

The X-ray crystal structures of three halo(tetramethylethylenediamine)copper(I) complexes have been determined. (TMED)₂Cu⁺CuCl ₂ ^– (I) crystallizes in monoclinic space groupP2₁/n with lattice constantsa=9.332(9),b=15.126(7),c=14.49(1) Å,=96.95(7)°. (TMEDCuBr)₂ (II) crystallizes in monoclinic space groupP2₁/c with lattice constantsa=12.064(5),b=11.888(6),c=15.841(6) Å,=113.97(3)°. (TMED CuI)₂ (III) crystallizes in monoclinic space groupP2₁/c with lattice constantsa=12.401(6),b=12.159(6),c=15.412(9) Å,=109.12(4)°. Compound (I) is a molecule exhibiting two discrete environments for copper(I). The cation is a pseudotetrahedral monomer and the anion a linear monomer. Both (II) and (III) are dimers with asymmetrically bridging bromine and iodine atoms, respectively. Distortions from tetrahedral geometry are observed about the copper atoms in (II) and (III).     

Synthesis,Characterization, and Structure of a Cyano-bridged Two-dimensional Cu<Superscript>II</Superscript>Co<Superscript>III</Superscript> Coordination Polymer Derived from <Emphasis Type="Italic">Trans</Emphasis>-1,2-diaminocyclohexane as Blocking Ligand

Abstract  The synthesis, characterization, and structure of a cyano-bridged two-dimensional supramolecule, [Cu^II(trans-chxn)₂]₃[Co^III(CN)₆]₂·2H₂O (1; chxn = 1,2-diaminocyclohexane), have been described. The title compound crystallizes in the triclinic Pī space group with the unit cell parameters: a = 9.141(5) ?, b = 12.406(5) ?, c = 15.064(5) ?, α = 95.190(5)°, β = 94.460(5)°, γ = 109.510(5)°, V = 1593.0(12) ?³, and Z = 1. The compound contains two crystallographically different copper(II) and cobalt(III) centers. Each of the two copper(II) ions is hexacoordinated by two diamines and two bridging cyanides. Two trans cyanides of one type of hexacyanometalate link one type of copper(II) center to result in one-dimensional chain, while two pairs of trans cyanides of the second type of hexacyanometalate link both the types of copper(II) ions to result in the second dimension. There are extensive hydrogen bonding interactions within the two-dimensional cyano-bridged sheet involving the solvated water molecule, amine groups, and cyanide nitrogens. Index Abstract  Synthesis, characterization, and structure of a cyano-bridged two-dimensional Cu^IICo^III coordination polymer derived from trans-1,2-diaminocyclohexane as blocking ligand Malabika Nayak, Samit Majumder, Pascale Lemoine, and Sasankasekhar Mohanta* The synthesis, characterization, and structure of a cyano-bridged two-dimensional supramolecule, [Cu^II(trans-chxn)₂]₃[Co^III(CN)₆]₂ · 2H₂O (chxn = 1,2-diaminocyclohexane), have been described.      

Crystal structure and vibrational spectra of polyamine-copper(II) complexes

The structures of [Cu(en)(H₂O)₂]SO₄ (I), [Cu(en)₂](NO₃)₂ (II) and [Cu(trien)I]I (III) have been determined by single crystal X-ray diffraction. ComplexI is monoclinic, space group C2/c, with unit cell parametera=7.232(1),b=11.725(2),c=9.768(1), =105.50(1)°, andZ=4. ComplexII is also monoclinic, space group P2₁/a, witha=7.978(2),b=9.982(4),c=8.218(3), =111.11(2)°, andZ=2. ComplexIII is orthorhombic, space group P2₁2₁2₁, witha=8.098(1),b=11.902(1),c=13.682(2), andZ=4. The structures were solved by direct methods and refined by full-matrix least-squares to finalR values of 0.031, 0.043 and 0.036 for complexesI, II, andIII, respectively. ComplexesI andII show an octahedral coordination geometry. ComplexIII shows a square pyramidal coordination geometry. ComplexI forms infinite monodimensional chains where the SO ₄ ^2– ions acts as a bridge between two neighboringen molecules. The vibrational spectra of these complexes agree well with their crystal structures. Structure and stability of seven other related Cu(II) complexes of (trien), (dien)₂, (en)₂ and (en) are inferred in this study.     

Crystal and molecular structure of Sr2( Edta ) · 5H2O, Sr2(H2 Edta )(HCO3)2 · 4H2O, and Sr2(H2 Edta )Cl2 · 5H2O strontium ethylenediaminetetraacetates

Three Sr²⁺ compounds with the Edta ⁴⁻ and H₂ Edta ²⁻ ligands—Sr₂(Edta) · 5H₂O (I), Sr₂(H₂ Edta)(HCO₃)₂ · 4H₂O (II), and Sr₂(H₂ Edta)Cl₂ · 5H₂O (III)—are synthesized, and their crystal structures are studied. In I, the Sr(1) atom is coordinated by the hexadentate Edta ⁴⁻ ligand following the 2N + 4O pattern and by two O atoms of the neighboring ligands, which affords the formation of zigzag chains. The Sr(2) atom forms bonds with O atoms of five water molecules and attaches itself to a chain via bonds with three O atoms of the Edta ⁴⁻ ligands. The Sr(1)-O and Sr(2)-O bond lengths fall in the ranges 2.520(2)–2.656(3) and 2.527(3)–2.683(2) ?, respectively. The Sr(1)-N bonds are 2.702(3) and 2.743(3) ? long. In II and III, the H₂ Edta ²⁻ anions have a centrosymmetric structure with the trans configuration of the planar ethylenediamine fragment. The N atoms are blocked by acid protons. In II, the environment of the Sr atom is formed by six O atoms of three H₂ Edta ligands, two O atoms of water molecules, and an O atom of the bicarbonate ion, which is disordered over two positions. In III, the environment of the Sr atom includes six O atoms of four H₂ Edta ²⁻ ligands and three O atoms of water molecules. The coordination number of the Sr atoms is equal to 8 + 1. In II and III, the main bonds fall in the ranges 2.534(3)–2.732(2) and 2.482(2)–2.746(3) ?, whereas the ninth bond is elongated to 2.937(3) and 3.055(3) ?, respectively. In II, all the structural elements are linked into wavy layers. The O-H…O interactions contribute to the stabilization of the layer and link neighboring layers. In III, hydrated Sr²⁺ cations and H₂ Edta ^– anions form a three-dimensional [Sr₂(H₂ Edta)(H₂O)₃] _n ²ⁿ⁺ framework. The Cl⁻ anions are fixed in channels of the framework by hydrogen bonds with four water molecules. In II and III, the N-H groups form four-center N-H…O₃ hydrogen bonds, which include one intermolecular and two intramolecular components. PACS numbers: 61.66.Hq Original Russian Text ? I.N. Polyakova, A.L. Poznyak, V.S. Sergienko, 2009, published in Kristallografiya, 2009, Vol. 54, No. 2, pp. 262–267.     

Synthesis,Crystal Structure Properties of {μ-Nitrato-[<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-ethylene-bis(3-methoxysalicylideneimin) diaqua nitrato Cu(II)La(III)]nitrat}

Abstract  

The [μ-NO₃-LCuLa(NO₃)·(H₂O)₂]NO₃ (I) complex has been prepared and characterized by single crystal X-ray diffraction properties. The title compound crystallizes in the monoclinic system, space group P 2₁/c, with a = 9.1699(4), b = 21.6796(8), c = 13.7068(6) ?, α = γ = 90o, β = 111.308(3)°, V = 2538.63 (18) ?³ and Z = 4. The unit cell contains four discrete the title compounds. The central region is occupied by Cu^II and La^III ions which are brigged by two phenolato oxygen atoms of ligand. The intramolecular La–Cu distance is 3.5016 (3) Ǻ. The copper (II) ion is in a distorted square pyramidal geometry with the imino nitrogen atoms N1 and N2, and the phenolic oxygen atoms O2 and O3 forming the square base. The La^III ion is deca coordinated.     

Syntheses, Structures, Fluorescence and Magnetic Property of Two Complexes with the Asymmetric dpa Ligand

Abstract  

Two compounds [Zn(Hdpa)₂(2,2′-bipy)]₂ (1) and [Mn(dpa)(4,4′-bipy)] _n (2) (H₂dpa=2,2′-biphenyldicarboxylate, bipy=dipyridine) are synthesized by hydrothermal reactions and structurally characterized by Single crystal X-ray diffraction analyses. Compound 1 is a dual-core molecular structure of two Zn ions in the same coordination environment, we studied the fluorescence of compound 1. Compound 2 is a layer structure based on the one-dimensional chains bridged by 4,4-bipy, it displays weak antiferromagnetic interactions between the inter-chain Mn²⁺ ions.     

Synthesis and Crystal Structure of MnII(OAc)2[15-MC MnIII(N)shi-5](Im)3(EtOH)3 (shi3??=?salicylhydroximate, ?OAc?=?acetate, Im?=?imidazole, and EtOH?=?ethanol)

Abstract  

The metallacrown complex Mn^II(OAc)₂[15-MC_Mn^III _(N)shi-5](Im)₃(EtOH)₃ has been synthesized and characterized by single-crystal X-ray diffraction and infrared spectroscopy. The compound crystallizes in the monoclinic space group P2₁/c with a = 24.3326(15) ?, b = 24.0354(15) ?, c = 27.0531(17) ?, α = 90.00°, β = 100.3883(11)°, γ = 90.00°, V = 15562.5(17) ?³, Z = 4, and Z′ = 2. Four of the five manganese(III) ions of the metallacrown ring adopt a distorted octahedral coordination geometry, and the fifth manganese(III) ion is five coordinate and exhibits a distorted square pyramidal environment. The configuration of the manganese(III) ions about the ring follows a pattern of ΔΛΔPP, with P representing planar. In addition, the imidazole units are bound to three separate ring manganese(III) ions, and the imidazole units are directed to the outside of the molecule. A manganese(II) ion is encapsulated in the central core of the molecule, and the central ion is seven coordinate with a face-capped trigonal prismatic geometry.     

Structural Characterization of Heterodinuclear ZnII-LnIII Complexes (Ln = Pr,Nd) with a Ring-Contracted H2valdien-Derived Schiff Base Ligand

Synthesis and structural characterization of two heterodinuclear Zn^II-Ln^III complexes with the formula [ZnLn(HL)(µ-OAc)(NO₃)₂(H₂O)_x(MeOH)_1-x]NO₃ · n H₂O · n MeOH [Ln?=?Pr (1), Nd (2)] and the crystal and molecular structure of [ZnNd(HL)(µ-OAc)(NO₃)₂(H₂O)] [ZnNd(HL)(OAc)(NO₃)₂(H₂O)](NO₃)₂ · n H₂O · n MeOH (3) are reported. The asymmetrical compartmental ligand (E)-2-(1-(2-((2-hydroxy-3-methoxybenzylidene)amino)-ethyl)imidazolidin-2-yl)-6-methoxyphenol (H₂L) is formed from N¹,N³-bis(3-methoxysalicylidene)diethylenetriamine (H₂valdien) through intramolecular aminal formation, resulting in a peripheral imidazoline ring. The structures of 1–3 were revealed by X-ray crystallography. The smaller Zn^II ion occupies the inner N₂O₂ compartment of the ligand, whereas the larger and more oxophilic Ln^III ions are found in the outer O₂O₂’ site.

Graphic Abstract

Synthesis and structural characterization of two heterodinuclear Zn^II-Ln^III complexes (Ln?=?Pr, Nd) bearing an asymmetrical compartmental ligand formed in situ from N¹,N³-bis(3-methoxysalicylidene)diethylenetriamine (H₂valdien) through intramolecular aminal formation are reported.

     

Palladium (II) compounds with diaminocarboxylic acids: Crystal structures of [Pd(H2Cdta)] · H2O, [Pd(H3Edtp)Cl] · 2H2O, and (H6Edtp)[PdCl4] · 4H2O

The crystal structures of three Pd(II) compounds with diamine tetracarboxylates in different protonation states are determined, namely, [Pd(H₂ Cdta)] · H₂O (I), [Pd(H₃ EdtpCl] · 2H₂O (II), and (H₆ Edtp)[PdCl₄] · 4H₂O (III) (R ₁ = 0.0230, 0.0313, and 0.0277 for 3040, 3377, and 3809 reflections with I > 2σ(I) for I–III, respectively). Crystals I and II are built of neutral complexes [Pd(H₂ Cdta)] and [Pd(H₃ Edtp)Cl], respectively, and crystallization water molecules. Crystal III consists of [PdCl₄]²⁻ anionic complexes, H₆ Edtp ²⁺ cations, and water molecules. In I, one of the protonated acetate groups of the H₂ Cdta ²⁻ ligand forms a very weak additional Pd-O bond [2.968(2) Å] over the 2N + 2O coordination square. In II and III, the protonated propionate groups of the H₃ Edtp ⁻ ligand and the H₆ Edtp ²⁺ cation are not involved in Pd coordination and the coordination squares consist of the 2N + O + Cl and 4Cl atoms, respectively. __________ Translated from Kristallografiya, Vol. 48, No. 2, 2003, pp. 278–282. Original Russian Text Copyright ? 2003 by Polyakova, Poznyak, Sergienko.