Crown-substituted Sc(III) phthalocyaninates: Synthesis and spectral properties

The scandium(III) complexes with tetra(15-crown-5)phthalocyanine [Sc(R₄Pc)₂]^·0 (I) and Sc(R₄Pc) · OAc (II) have been synthesized by condensation of Sc³⁺ with phthalocyanine H₂R₄Pc (4,5,4′,5′,4″,5″,4?,5?-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyanine). Compounds I and II have been characterized by spectral methods: electronic absorption spectroscopy, MALDI-TOF MS, IR spectroscopy, and ¹H NMR. The redox properties of I and the photoluminescent properties of II have been studied.     

Synthesis,Structure, and Magnetic Properties of a Twist Linear Tetranuclear Co<Stack><Subscript>2</Subscript><Superscript>III</Superscript></Stack>Ln<Stack><Subscript>2</Subscript><Superscript>III</Superscript></Stack> Complexes

A series of twist linear tetranuclear 3d–4f Co ₂ ^III Ln ₂ ^III [Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5)] complexes have been prepared under solvothermal conditions and structurally characterized with Schiff-base ligand 2-(((2-hydroxy-3-methoxyphenyl)methylene)amino)-2-(hydroxymethyl)-1,3-propanediol (H₄L). The two central Co ions are linked by two alkoxyl oxygen atoms, and one Ln ion lying above and the other below the Co–Co dimer, form a twist linear array. The magnetic susceptibility studies reveal antiferromagnetic or ferromagnetic behaviour, whilst dynamic magnetic studies indicate no slow magnetic relaxation for these complexes.     

Synthesis,structure, and optical properties of lanthanum(III), cerium(III), praseodymium(III), and nickel(II) heterometallic complexes with glycine

New cluster complexes of lanthanides(III) and nickel(II) [Ln{Ni(Gly)₂}₆]³⁺[Ln(NO₃)₆]^3– have been synthesized, where Ln = La (I), Ce (II), and Pr (III); and Gly is glycinate. The structures of compounds I–III are determined by X-ray diffraction. The icosahedral cavity in the complex cation, where the lanthanide ion resides, has a fixed size independent of the nature of the central Ln(III) ion. In the complex anion, on the contrary, the Ln–O distances naturally decrease from La(III) to Pr(III). The optical properties of cationanion complexes I–III are studied. Based on the assignment in the electronic absorption spectra of the complexes, it is shown that the absorption bands are caused by d–d electronic transitions.     

The activation of C-H bonds in C<Subscript>1</Subscript>-C<Subscript>3</Subscript> alkanes by zirconium(III,IV) and titanium(III,IV) hydrides immobilized on the surface of SiO<Subscript>2</Subscript>: a density functional theory study

Model reactions of the (≡Si-O-)₃M^IVH (1), (≡Si-O-)₂M^IVH₂ (2), and (≡Si-O-)₂M^IIIH (3) hydrides, where M = Ti and Zr, immobilized on the surface of silica with methane and propane were studied by the density functional theory with the PBE functional. The reactions involved the breaking of C-H alkane bonds and the formation of the (≡Si-O-)₃MR, (≡Si-O-)₂M(H)R, and (≡Si-O-)₂MR products (R = Me, n-Pr, and i-Pr), respectively. Reactions with the participation of 1 and 2 were found to occur as bimolecular processes without the formation of agostic-type prereaction complexes. With 3, the reaction was accompanied by the formation of stable prereaction and postreaction complexes. The conclusion was drawn that dihydrides 2 and trivalent metal hydrides 3 were much more reactive with respect to alkane C-H bonds than monohydrides 1. All the systems studied were characterized by low reaction regioselectivities.     

Synthesis,crystal structures,and properties of copper(II) dicarboxylate complexes with [bis(2-pyridylcarbonyl)amido]

Four new complexes, [Cu₂(Bpca)₂(L¹)(H₂O)₂] · 3H₂O (I), [Cu₂(Bpca)₂(L²)(H₂O)₂] (II), [Cu₂(Bpca)₂(L³)] · 2H₂O (III), [Cu₂(Bpca)₂(L¹)(H₂O)] · 2H₂O (IV) (Bpca = bis(2-pyridylcarbonyl)amido, H₂L¹ = glutaric acid, H₂L² = adipic acid, H₂L³ = suberic acid, H₂L⁴ = azelaic acid) have been synthesized and characterized by single-crystal X-ray diffraction methods (CIF files CCDC nos. 1432836 (I), 1432835 (II), 817411 (III), and 817412 (IV)), elemental analyses, IR spectra. Structural analyses reveal that compounds I, II, and IV have similar structures [Cu(Bpca)]⁺ units bridged by dicarboxylate forming dinuclear units, whereas the dinuclear of compound III are edge-shared through two carboxylate oxygen atoms of different suberate anions. Hydrogen bonds are response for the supramolecular assembly of compounds I to IV. The temperature-dependent magnetic property of III was also investigated in the temperature range of 2 to 300 K, and the magnetic behaviour suggests weak antiferromagnetic coupling exchange.     

New complexes of tris(2-aminoethanolato-O,N)cobalt(III) sulfates: Synthesis and structure

The reaction of [Co(Etm)₃] · 3H₂O (I) with sulfuric acid affords [Co(HEtm)₃]₂(SO₄)₃ · 4H₂O (II). The change in the synthesis procedure (the direction interaction of cobalt(II) sulfate with β-aminoethanol (HEtm)) makes it possible to isolate [Co(HEtm)₃](SO₄)(HSO₄) · H₂O (III) and {[Co(HEtm)₃][Co(Etm)₃]}₂(SO₄)₃ · 7.75H₂O (IV). The X-ray diffraction analyses of compounds II–IV show that all of them are of the ionic type. In compounds II and III, the ionic structure consists of the [Co(HEtm)₃]₃₊ cations and sulfate anions in a ratio of 2: 3 and 1: 2, respectively. The basic difference in compounds II and III is the different degrees of deprotonation of the acid residues. In complex II, two anions SO ₄ ^2? are doubly deprotonated. In complex III, of the four anions found in the independent part of the unit cell of the sulfate anion two anions are monodeprotonated. In structure IV, two crystallographically independent complexes [Co(HEtm)₃]³⁺ and [Co(Etm)₃] are joined into a dimer through the O-H?O hydrogen bonding.     

Cobalt(III) complexes with biguanide derivatives: Synthesis,structures, and antiviral activity

Three Co(III) complexes with biguanide derivatives [Co(NH₂C(=NH)NHC(=NH)NR¹R²)₃]Cl₃ (R¹R² = Me₂ (I), Et₂ (II), and H^sBu (III)) were obtained and characterized by elemental analysis, IR spectroscopy, and electronic absorption spectroscopy. Structure III was confirmed by X-ray diffraction (CIF file CCDC no. 1401783). Complexes I–III and [M(SC(NH₂)₂)₄]Cl₂ (M = Pd, Pt, and [Co(En)₃]Cl₃) were tested for in vitro antiviral activity against the A/California/07/09 (H1N1pdm09) influenza virus. The best results were achieved with complex III and both thiourea complexes.     

Hexa(isothiocyanato)chromates(III) of Some Yttrium Group Lanthanide(III) and Europium Complexes with Nicotinic Acid: Synthesis and Crystal Structures

Double ionic complexes [M(C₅H₅NCOO)₃(H₂O)₂][Cr(NCS)₆] · nH₂O, where M = Eu (I), n = 1.15; Dy (II), Er (III), n = 1.5; M = Yb (IV), n = 2, have been synthesized by the reaction between M(NO₃)₃, M = Eu, Dy, Er, Yb, K₃[Cr(NCS)₆], and nicotinic acid (C₅H₅NCOO) in an aqueous solution and studied by chemical analysis, IR spectroscopy, and X-ray diffraction. Crystals of complexes I–IV are monoclinic, space group P2₁/n, Z = 4; a = 9.5358(2) Å, b = 25.4871(5) Å, c = 15.4303(4) Å, β = 105.513(1)°, V = 3613.6(1) ų, ρ_calcd = 1.799 g/cm³ for I, a = 9.5901(5) Å, b = 25.8599(15) Å, c = 15.6316(9) Å, β = 106.829(2)°, V = 3710.6(4) ų, ρ_calcd = 1.782 g/cm³ for II, a = 9.5640(3) Å, b = 25.8936(11) Å, c = 15.6498(7) Å, β = 106.895(2)°, V = 3708.3(3) ų, ρ_calcd = 1.791 g/cm³ for III, and a = 9.5049(2) Å, b = 25.6378(4) Å, c = 15.5120(3) Å, β = 106.934(1)°, V = 3616.1(1) ų, ρ_calcd = 1.864 g/cm³ for IV.     

Effect of solvent on the crystal structures of copper(II) complexes based on 4′-(4-methoxyphenyl)-2,2′:6′,2″-terpyridine and 4′-(3-chlorophenyl)-2,2′:6′,2″-terpyridine

Four homoleptic copper(II) complexes, [Cu(Meophtpy)₂](ClO₄)₂ (Meophtpy = 4′-(4-methoxylphenyl)- 2,2′:6′,2″-terpyridine) (I), [Cu(Meophtpy)₂](ClO₄)₂ · 2H₂O (II), [Cu₂(m-Clphtpy)₄](ClO₄)₄ (m-ClPhtpy = 4′-(3-chlorophenyl)-2,2′:6′,2″-terpyridine) (III), and [Cu₂(m-ClPhtpy)₄](ClO₄)₄ (IV) have been synthesized by hydrothermal methods and characterized by IR, elemental analysis and single crystal X-ray diffraction (CIF files CCDC nos. 963375 (I), 885457 (II), 963377 (III), and 963376 (IV)). Complex II is a polymorph of I and complex IV is a polymorph of III. All these complexes are obtained with 95% ethanol solution or 50% ethanol solution and the solvent control on the crystallization are obviously found. In all complexes, the face-to-face interactions between pyridyl rings or phenyl rings facilitate the construction of 3D network in the crystal in addition to hydrogen bonds. The fluorescence properties of these complexes have been investigated.     

Crystal structures of polyphosphates MCs<Subscript>5</Subscript>(PO<Subscript>3</Subscript>)<Subscript>8</Subscript> (M = Pr,Eu, and Gd)

Crystals of double polyphosphates EuCs₅(PO₃)₈ (I) and GdCs₅(PO₃)₈ (II) have been studied by X-ray diffraction. The isostructural crystals of I and II are monoclinic, space group C2. Only unit cell parameters have been determined for the crystals of double Pr and Cs polyphosphate (III). This crystal is isostructural with earlier studied La₃Cs₁₅P₂₄O₇₂ · 6H₂O (IV). The crystals of compounds III and IV are triclinic, space group P1, Z = 1; a = 11.987(2) and 12.178(5) Å, b = 14.754(8) and 14.740(8) Å, c = 14.692(8) and 14.847(9) Å, α = 60.15(4)° and 60.87(5)°, β = 67.04(4)° and 66.35(4)°, γ = 78.76(3)° and 77.54(4)°, respectively. In compounds I and II, the polyphosphate anions exist as infinite chains. The M^IIIO₈ polyhedra are isolated from each other but share edges and faces with the CsO _n polyhedra.     

Structure of binuclear platinum(III) acetamidate complexes in solutions as probed by <Superscript>195</Superscript>Pt, <Superscript>13</Superscript>C,and <Superscript>1</Superscript>H NMR spectroscopy

¹⁹⁵Pt, ¹H, and ¹³C NMR spectroscopy was used to study the structure of binuclear platinum(III) acetamidate complexes with 1,10-phenanthroline and 2,2′-bipyridine ligands [Pt₂(phen)₂(acam)₄](NO₃)₂ (1) and [Pt₂(bipy)₂(acam)₄](NO₃)₂ (2) in aqueous solutions. The ¹⁹⁵Pt NMR spectra of solutions of complexes 1 and 2 in D₂O exhibit two signals with satellites due to the ¹⁹⁵Pt–¹⁹⁵Pt spin-spin coupling (¹ J(Pt–Pt) ≈ 6345 Hz), whereas their ¹H and ¹³C NMR spectra contain four sets of signals for the protons and the carbon atoms of the heterocyclic and acetamidate ligands. The signals were assigned using the COSY, NOESY, and HSQC/ HMBC experiments and comparing the coordination shifts of the signals for the protons of heterocycles. These data allowed us to draw a conclusion that binuclear complexes 1 and 2 in solution have a head-to-head structure with nonequivalent platinum(III) atoms (coordination cores PtN₅ and PtN₃O₂), the axial-equatorial coordination of the bidentate heterocyclic molecules, and two bridging and two terminal acetamidate ligands.     

Syntheses and structures of tris(<Emphasis Type="Italic">para</Emphasis>-tolyl)-, tris(3-fluorophenyl)-, and tris(4-fluorophenyl)antimony dioximates

Tris(para-tolyl)antimony bis(2-oxybenzaldoximate) (I), tris(para-tolyl)antimony bis(2-nitrobenzaldoximate) (II), tris(para-tolyl)antimony bis(2-bromobenzaldoximate) (III), tris(3-fluorophenyl)antimony bis(2-oxybenzaldoximate) (IV), tris(4-fluorophenyl)antimony bis(2-bromobenzaldoximate) (V), and tris(4-fluorophenyl)antimony bis(2-nitrobenzaldoximate) (VI) are synthesized by the reactions of tris(paratolyl)-, tris(3-fluorophenyl)-, and tris(4-fluorophenyl)antimony with 2-oxy-, 2-nitro-, and 2-bromobenzaldoxime in diethyl ether in the presence of tert-butyl hydroperoxide. The Sb atoms in complexes I–VI have a distorted trigonal bipyramidal coordination mode with the oximate ligands in the axial positions. CIF files CCDC nos. 1062231 (I), 1059962 (II), 1465384 (III), 1465109 (IV), 1471948 (V), and 1060387 (VI).     

Cobalt(II) and copper(II) complexes with chiral pyrazolylquinoline,a derivative of terpenoid (+)-3-carene. Catalytic activity in ethylene polymerization reaction

Coordination compounds [CoLCl₂] (I), [CuLCl(NO₃)] (II), CuL(NO₃)₂ (III), and CuLCl₂ (IV) (where L is a chiral pyrazolylquinoline—a derivative of terpenoid (+)-3-carene) were synthesized. X-ray diffraction data showed that crystal structures I and II are built of mononuclear acentric molecules. In the molecule of complex I, the Co₂₊ ion coordinates two N atoms of bidentate cycle-forming ligand L and two Cl atoms. The coordination polyhedron of Cl₂N₂ is a distorted tetrahedron. For complex I, μ_eff = 4.50 μ_B, which corresponds to a high-spin configuration d ⁷. In the molecules of II(1), II(2) (which are diastereoisomers of complex II), each Cu²⁺ ion coordinates two N atoms of bidentate cycle-forming ligand L, the Cl atom, and two O atoms of bidentate cyclic NO ₃ ^? ion. The ClN₂O₂ coordination polyhedra are tetragonal pyramids with different degrees of distortion. The structure of complex II consists of supramolecular clusters, i.e., isolated chains incorporating the molecules of II(1) and II(2). The values of μ_eff for II–IV correspond to the d ⁹ configuration. The results of EPR and IR study suggest that complex III contains the O₄N₂ polyhedron, whereas complex IV contains the Cl₂N₂ polyhedron. Complexes I and IV were found to show a high catalytic activity in ethylene polymerization reaction.     

New catecholate complexes of triphenylantimony(V) based on 6-iminomethyl-3,5-di-<Emphasis Type="Italic">tert</Emphasis>-butylpyrocatechols N-functionalized by the aniline or phenol group

The following new triphenylantimony(V) catecholate complexes bearing the protonated imine group are synthesized from the new sterically hindered 3,5-di-tert-butylpyrocatechols (6-(CH=N-o-(C₆H₄–NH₂))-3,5-Cat)H₂ (H₂L¹) and (6-(CH=N-o-(C₆H₄–OH))-3,5-Cat)H₂ (H₂L²) containing in position 6 the iminomethyl group bonded to the aniline or phenol substituent: (6-(CH=NH⁺-o-(C₆H₄–NH₂))-3,5-Cat)SbPh₃X (X = Br (I), OMe (III)) and (6-(CH=NH⁺-o-(C₆H₄–OH))-3,5-Cat)SbPh₃X (X = Br (II), OMe (IV)). The molecular structure of complex III · CH ₃ OH in the crystalline state is determined by X-ray diffraction analysis (CIF file CCDC no. 1554694). The electrochemical properties of complexes III and IV are studied by cyclic voltammetry.     

Lanthanide complexes with the Schiff base containing sterically hindered phenol: Synthesis,structure, and luminescence properties

The syntheses of the 2,6-di-tert-butyl-4-(2-hydroxybenzylideneamino)phenolate (L) complexes of Gd (I), Nd (II), Er (III), Yb (IV), Tm (V), Sm (VI), and Tb (VII) are described. The structures of the Gd and Er complexes are determined by X-ray diffraction analysis (CIF files CCDC nos. 1558820 (I) and 1558819 (III)). All synthesized compounds exhibit ligand-centered photoluminescence in a range of 405–485 nm. In addition, the luminescence spectra of solid samples of the neodymium and ytterbium complexes contain narrow bands of f–f transitions characteristic of Nd³⁺ and Yb³⁺ ions.     

Tris(5-bromo-2-methoxyphenyl)bismuth dicarboxylates [(C<Subscript>6</Subscript>H<Subscript>3</Subscript>(Br-5)(MeO-2)]<Subscript>3</Subscript>Bi[OC(O)CHal<Subscript>3</Subscript>]<Subscript>2</Subscript> (Hal = F,Cl): synthesis and structure

Tris(5-bromo-2-methoxyphenyl)bismuth dicarboxylates [(C₆H₃(Br-5)(MeO-2)]₃Bi[OC(O)CHal₃]₂, Hal = F (II) and Cl (III), have been synthesized by the reaction between tris(5-bromo-2-methoxyphenyl)bismuth (I) and trifluoroacetic acid and thrichloroacetic acid, respectively, in the presence of hydrogen peroxide in ether. According to X-ray diffraction data, a crystal of complex I contains two types of crystallographically independent molecules (a and b) both with a trigonal pyramid configuration. The bismuth atoms in complexes II and III have a distorted trigonal bipyramidal coordination with carboxylate substituents in axial positions. Axial OBiO angles are 166.3(3)° (II) and 171.6(2)° (III); equatorial CBiC angles are 118.0(3)°–123.1(3)° (II) and 113.6(3)°–127.4(3)° (III). Bi–C bond lengths are 2.189(7)–2.200(8) Å (II) and 2.190(8)–2.219(7) Å (III), and Bi–О distances are 2.280(6), 2.459(16) Å (II) and 2.264(5), 2.266(5) Å (III). Intramolecular contacts between the central atom and the oxygen atoms of carbonyl groups (Bi···O 3.028(9), 3.162(9) Å (II); 3.117(9), 3.202(9) Å (III)) are observed at maximum equatorial angles. The oxygen atoms of methoxy groups are coordinated to the bismuth atom. The Bi···O distances in complexes II and III (3.028(16), 3.157(16), 3.162(16) and 3.17(16), 3.143(16), 3.202(16) Å, respectively) are slightly longer than in complex I (3.007(9)–3.136(4) Å).     

Cobalt(II) and nickel(II) cloride complexes with 4,5-(<Emphasis Type="Italic">n</Emphasis>-pyridylethylene)-dithio-1,3-dithiol-2-thiones (<Emphasis Type="Italic">n</Emphasis> = 2, 4)

The NiCl₂ and CoCl₂ complexes with 4,5-(2-pyridylethylene)-dithio-1,3-dithiol-2-thione (L¹) and 4,5-(4-pyridylethylene)-dithio-1,3-dithiol-2-thione (L²) were described. The L¹ ligand shows bidentate coordination through the pyridyl N atoms and the thiol S atoms in a tetrahedral [CoCl₂(L¹)] complex (I) and in an octahedral [NiCl₂(L¹)₂](MeCN)₂ complex (II). The L² ligand exhibits monodentate coordination through the pyridyl N atom in tetrahedral complexes [CoCl₂(L²)₂ (III) and [NiCl₂(L²)₂] (IV). Complexes I, III, IV in crystal state are octahedral due to extra coordination of the thione S atoms or the chloride bridges responsible for the polymeric structure. The structure of the complex II · CH₂Cl₂ was determined by X-ray diffraction analysis. The crystals are monoclinic, space group P2₁/c, a = 11.895(2) Å, b = 13.374(3) Å, c = 21.873(4) Å, β = 95.30(3)°, Z = 2. The Ni atom has quasi-tetrahedral surrounding due to two chloride ions and two L¹ ligands coordinated through the pyridyl N atoms and the thiol S atoms.     

Crystal chemical analysis of structures of the unsaturated tetraazamacrocyclic gold(III) complexes

The detailed comparative study is carried out for crystal structure packings of the following gold(III) complexes with unsaturated ligands: [Au(C₁₄H₂₂N₄)]Br (I), [Au(C₁₄H₂₃N₄)](ClO₄)₂ (II), [Au(C₁₄H₂₄N₄)](H₃O)(ClO₄)₄ (III). The determining role in the topological pattern of packings I–III belongs to the compositions and structures of the cations along with the ability of the ions of the complexes to act as donors and acceptors of hydrogen bonds. The 3D packings of complexes I and II containing iminate six-membered rings are determined and stabilized by a wide network of weak hydrogen bonds (C–H…π, C–H…Au, and C–H…Br(O)) and short contacts Au(N)…O (in structure II). The structure of imine complex III is characterized by one-dimensional piles formed due to hydrogen bonds O(w)–H…O and contacts Au…O of the О(2) atom of anion Сl(1)О ₄ ^- with cations (H₃O)⁺ and [Au(C₁₄H₂₄N₄)]³⁺ (CIF files CCDC 251258 (I), 276132 (II), and 287784 (III)).     

X-ray study of rhodium(III) sulfates

Compounds with compositions [Rh(H₂O)₆]₂(SO₄)₃·4H₂O (I), (H₃O)[Rh(H₂O)₆](SO₄)₂ (II), [Rh(H₂O)₅OH](SO₄)·0.5H₂O (III), and [Rh(H₂O)₆]₂(SO₄)·(H₂SO₄) _x ·5H₂O (IV) have been studied. The crystal structures of II, III, and IV were determined. All compounds crystallized in the monoclinic crystal system. Crystal data for II: a = 7.279(2) Å, b = 10.512(7) Å, c = 15.806(3) Å, β = 96.71(3)°, space group P2₁/n, Z = 2, d _calc = 2.334 g/cm³; III: a = 20.433(4) Å, b = 7.820(2) c = 11.215(2) Å, β = 114.14(1)°, space group C2/c, Z = 8, d _calc = 2.559 g/cm³; IV: a = 6.2250(4 Å), b = 27.0270(12) Å, c = 7.2674(5) Å, β = 97.04(3)°, space group P2₁/c, Z = 4, d _calc = 2.143 g/cm³. The compounds were studied by IR spectroscopy and powder X-ray diffraction. All of the isolated crystalline phases are sparingly soluble in ethanol and well soluble in water.     

Synthesis and spectroscopic study of praseodymium(III) complexes with tetra-15-crown-5-phthalocyanine

Praseodymium(III) complexes with tetra-15-crown-5-phthalocyanine—the neutral radical [(R₄Pc^?·)Pr³⁺(R₄Pc^2?)]⁰ and one-electron reduced [(R₄Pc^2?)Pr³⁺(R₄Pc^2?)]^? forms of the sandwich double-decker complex and the triple-decker complex Pr₂(R₄Pc)₃ (R₄Pc^2? is [4,5,4′,5′,4″,5t",4″′,5″′-tetrakis(1,4,7,10,13-pentaoxatridecamethylene)phthalocyaninate ion])—have been synthesized and spectrally characterized. These compounds have been obtained by direct interaction of tetra-15-crown-5-phthalocyanine with praseodymium(III) acetate or acetylacetonate. The salt anion has an effect on the yield and structure of the reaction products. The complexes have been obtained in high yields, isolated, and characterized by different physicochemical methods: UV and visible electronic absorption spectroscopy, ¹H NMR, and MALDI-TOF mass spectrometry. The double-decker complex is stable in the solid state and in solutions. The triple-decker complex is stable only in the solid state. In a chloroform-methanol (10 vol %) solution, it slowly decomposes.