SYNTHESIS AND CRYSTAL STRUCTURE OF A BINUCLEAR COPPER (II) COMPLEX BRIDGED BY OXAMIDATO,Cu2(μ-CIS-OXPN)(PHEN)(NO3)2

Abstract

The complex [Cu₂(μ-cis-oxpn)(phen)(NO₃)₂], where oxpn = N,N′ -bis(3-aminopropyl) oxamidato and phen = 1,10-phenanthroline, has been synthesized and its crystal structure determined by X-ray methods. The structure consists of binuclear copper (II) molecules in which the Cu(II) atoms are bridged by oxamidato group in the cis conformation, the Cu—Cu distance being 5.205(10) Å. The coordination geometry around Cu (II) atoms is square pyramidal; the apex is occupied by a more weakly bonded O atom from a nitrate group. Electron delocalization is observed in the bridging oxamide moiety. The co-planarity of bridge ligand and basal plane around Cu (II) atoms may benefit spin super-exchange between two Cu (II) atoms. IR spectra of the binuclear complex are discussed.     

The two‐dimensional coordination polymer poly[diaqua(μ2‐1H‐imidazo[4,5‐f][1,10]phenanthroline)‐μ4‐sulfato‐μ3‐sulfato‐dicadmium(II)]

In the title coordination polymer, [Cd₂(SO₄)₂(C₁₃H₈N₄)(H₂O)₂]_n, there are two crystallographically independent Cd^II centres with different coordination geometries. The first Cd^II centre is hexacoordinated by four O atoms of four sulfate ligands, one water O atom and one N atom of a 1H‐imidazo[4,5‐f][1,10]phenanthroline (IP) ligand, giving a distorted octahedral coordination environment. The second Cd^II centre is heptacoordinated by four O atoms of three sulfate ligands, one water O atom and two N atoms of one chelating IP ligand, resulting in a distorted monocapped anti‐trigonal prismatic geometry. The symmetry‐independent Cd^II ions are bridged in an alternating fashion by sulfate ligands, forming one‐dimensional ladder‐like chains which are connected through the IP ligands to form two‐dimensional layers. These two‐dimensional layers are linked by interlayer hydrogen bonds, leading to the formation of a three‐dimensional supramolecular network.     

Bimetallic bis(diphenylphosphino)acetylene bridged copper(I) complexes with 1,10-phenanthroline derivatives: synthesis,crystal structure,and spectroscopic characterization

A new series of bimetallic bis(diphenylphosphino)acetylene-bridged copper(I) 1,10-phenanthroline complexes, [Cu₂(dppa)₂(L)₂](BF₄)₂; L?=?1,10-phenanthroline (1); 4-methyl-1,10-phenanthroline (2); 4,7-dimethyl-1,10-phenanthroline (3); and 2,9-dimethyl-1,10-phenanthroline (4), have been prepared and characterized by spectroscopic methods. The X-ray structures of 1 and 4 were determined. The structures consist of centrosymmetric bimetallic 10-membered chair-like dimetallacycles. In 1, intermolecular C–H?π interactions result in bending of the phenanthroline ligand and sterically induced lengthening of one Cu–P bond. In 1–4, the ³¹P NMR downfield coordination shift, relative to the free ligand, correlates with the basic strength of the 1,10-phenanthroline ligands.     

A 2D lanthanum coordination polymer with π–π stacking

A 2D lanthanum coordination polymer La₂(1,10-phen)₂(e,a-cis-1,4-chdc)₃ · 2.5H₂O (chdc = cyclohexanedicarboxylic acid; phen = 1,10-phenanthroline) 1 which contains two-dimensional (2-D) lanthanum-organic sheets, was prepared under hydrothermal conditions and characterized by elemental analyses, IR spectra, TG analysis, and single-crystal X-ray diffraction. In the structure of 1, the La site is nine-coordinate by two nitrogen atoms from 1,10-phen and seven oxygen atoms from several 1,4-chdc ligands, connected into a 2-D coordination polymer, with the flexible 1,4-chdc spacers. The 2-D layers are extended into a 3-D framework by π–π interactions between adjacent layers.     

1-D chain Cd(II) compound based on flexible phenylenediacetic ligand: synthesis,crystal structure,and fluorescent properties

A coordination polymer of Cd^II with a flexible ligand in [Cd(Hpda)₂(4,4′-bipyridyl)₂]?·?(H₂O)₂ (1) (H₂pda?=?1,2-phenylenediacetic acid) has been synthesized by hydrothermal reactions and characterized by IR, TG, fluorescent spectrum, X-ray powder diffraction, and single-crystal X-ray diffraction techniques. The results show that 1 is monoclinic, with space group P2(1)/c, a?=?1.1704(7), b?=?1.7206(1), and c?=?2.2073(1) nm, β?=?120.881(2)°. In 1, the Cd(II) ions are linked by 4,4′-bipyridyl ligands to form 1-D chain with the arms of 1,2-pda ligands. These chains are imbedded into each other to form 2-D supramolecular sheets through hydrogen bonds. Adjacent 2-D sheets are assembled to 3-D network architecture through the crystallization of water molecules. Photoluminescence properties of 1 were investigated in the solid state at room temperature. The spectrum shows intense photoluminescence at 300?nm (λ_ex?=?275?nm).     

Self-assembled tetrameric H2O clusters in the crystal lattice of [Cu(μ2-OH){Ph2P(O)NP(O)Ph2-κ1O,O′}(1,10-phen-κ2N,N′)]2·2H2O

Abstract

The synthesis and characterization of the dinuclear Cu(II) complex [Cu(μ²-OH){Ph₂P(O)NP(O)Ph₂-κ¹O,O′}(1,10-phen-κ²N,N′)]₂·2H₂O (1), 1,10-phen?=?1,10-phenanthroline, is described. X-ray crystallographic studies reveal that the Cu(II) centers of 1 are bridged by two OH^? groups and are coordinated by the (O,O)?= Ph₂P(O)NP(O)Ph₂^? ligand in a monodentate fashion, unprecedented for Cu(II). The crystal lattice of 1 also contains H₂O molecules, which are involved in the formation of a hydrogen bonding network with bridging OH^? groups and noncoordinated O atoms of the (O,O) ligand. These H₂O molecules are arranged in the crystal lattice of 1 as tetrameric clusters. The packing of molecules in the structure of 1 was investigated by Hirshfeld Surface analysis.     

Synthesis and properties of ruthenium(II) complexes of 3,3′-polymethylene-2-(pyrid-2′-yl)benzo[b]-1,10-phenanthrolines

Coordination abilities of unsymmetrical tridentate ligands, 3,3′-polymethylene-2-(pyrid-2′-yl)-benzo[b]-1,10-phenanthrolines (4) were studied. Reactions of the 3,3′-di- and 3,3′-trimethylene-2-(pyrid-2′-yl)benzo[b]-1,10-phenanthrolines (4b and 4c) with RuCl₃ ? 3H₂O afforded [Ru(4b)₂]²⁺ and [Ru(4c)₂]²⁺ in 57% and 78% yield, respectively, while reactions of the parent non-bridged ligand (4a), tetramethylene-bridged ligand (4d), and fully aromatized ligand (4e) afforded a messy mixture. Reactions of 4 with Ru(tpy)Cl₃ (tpy = 2,2′;6′,2″-terpyridine) afforded [Ru(tpy)(4)]²⁺ in 61–72% yields. UV absorption spectra of the ligands showed four ligand-centered (LC) π–π* transitions and their Ru complexes showed four LC π–π* transitions and one Ru(d_π) → ligand(π*) MLCT. The ligands showed three major emission maxima (λ _emission) in the region of 393–418, 416–445, and 437–471 nm in which λ _emission is highly dependent on the length of the methylene bridge connecting C3 of benzo[b]-1,10-phenanthroline and C3 of pyridine. Ru complexes with fully aromatic ligand, [Ru(tpy)(4e)]²⁺, and the most distorted ligand, [Ru(tpy)(4d)]²⁺, showed two emission maxima at 410 and 444–446 nm, while the others showed one emission at 410 nm. Each of the emission maxima is bathochromatically shifted from the complex with the most distorted ligand (4d) to the complex with fully aromatized planar ligand (4e) indicating lower energy emission.     

Effect of the ancillary ligands on the binding of ruthenium(II) complexes [Ru(dmp)2(MCMIP)]2+ and [Ru(dmb)2(MCMIP)]2+ with DNA

Two polypyridine ruthenium(II) complexes, [Ru(dmp)₂(MCMIP)]²⁺ (1) (MCMIP = 2-(6-methyl-3-chromonyl)imidazo[4,5-f][1,10]-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline) and [Ru(dmb)₂(MCMIP)]²⁺ (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine), have been synthesized and characterized by elemental analysis, ES-MS and ¹H NMR. The DNA-binding behaviors of these complexes were investigated by electronic absorption titration, fluorescence spectroscopy, viscosity measurements and thermal denaturation. The results show that 1 and 2 effectively bind to CT-DNA; the DNA-binding affinities are closely related to the ancillary ligand.     

Two new lead(II) nitrite complexes,crystal structure of [Pb(phen)2(NO2)2] an eight-coordinate lead(II) complex

Two new lead(II) complexes containing nitrite, [Pb(L)₂(NO₂)₂], L?=?1,10-phenanthroline (phen) or 2,2′-bipyridine (bpy), have been synthesized and characterized. The crystal structure of [Pb(phen)₂(NO₂)₂] shows monomeric units. The coordination number is eight (four from “phen” ligands and four nitrite anions), weak interaction of lead(II) with oxygen atoms of adjacent molecules produce dimer units in the solid state. The arrangement of ligands exhibits a coordination hole around the lead(II), occupied possibly by a stereoactive lone pair of electrons on lead(II), and the coordination around lead is hemidirected. There is a π–π stacking interaction between the parallel aromatic rings that may help to increase the “gap” around lead(II).     

Tuning topological and dimensional versatility from 1D to 3D of Zn/Cd luminescent biphenyl-3,5-dicarboxylate coordination polymers by ancillary ligand

The present study reports application of biphenyl-3,5-dicarboxylic acid (H₂L) as a versatile building block for synthesis of d¹⁰ metal coordination polymers (CPs). Five Cd(II) and Zn(II)-containing CPs based on N,N-donor ancillary ligands, [Cd₂(μ₃-L)₂(μ₂-4,4′-tmbpy)(MeOH)]_∞ (1), [Cd(μ₂-L)(2,2′-bpy)(H₂O)]_∞·n(MeOH) (2), [Cd(μ₂-L)(dipt)]_∞ (3), [Cd(μ₃-L)(phen)]_∞·nH₂O (4), and [Zn(μ₂-L)(μ₂-4,4′-tmbpy)]_∞·nH₂O (5) {4,4′-tmbpy = 4,4′-trimethylenedipyridine, 2,2′-bpy = 2,2′-bipyridine, dipt = 2,9-dimethyl-1,10-phenanthroline, phen = 1,10-phenanthroline} have been prepared under solvothermal conditions. 1–5 have been characterized by single crystal X-ray diffraction, elemental analysis, infrared (IR) spectra, and powder X-ray diffraction (PXRD). Complex 1 exhibits a three-dimensional (3-D) framework with a rare fsc-3,4-I41/amd topology. Complexes 2–4 show one-dimensional (1-D) structures. Complex 5 features a two-dimensional (2-D) layer structure with a sql topology. The structural and topological diversity of 1–5 are mainly attributed to the effect of the N,N-donor ancillary ligand. Solid-state luminescent properties and thermal stabilities of the obtained products have been investigated.     

Synthesis and crystal structures of ruthenium(II) complexes with polypyridyl: [Ru(bpy)2(AFO)](ClO4)2 · H2O and [Ru(dmp)2 (AFO)](ClO4)2 · 1/2DMF · 1/2MeCN

Two ruthenium(II) complexes with polypyridyl ligands, [Ru(bpy)₂(AFO)](ClO₄)₂ · H₂O (1) and [Ru(dmp)₂ (AFO)](ClO₄)₂ · 1/2DMF · 1/2MeCN (2) (bpy = 2,2′-bipyridine; dmp = 2,9-dimethyl-1,10-phenanthroline; AFO = 4,5-diazafluoren-9-one; DMF = N,N-dimethylformamide), were synthesized and characterized by elemental analyses, i.r. and u.v.-vis. spectra. The structures of the two complexes were determined by single crystal X-ray diffraction techniques. To relieve ligand interaction, the coordination sphere is distorted so as to form specific angles (δ) between the polypyridyl ligand planes and coordination planes (N-Ru-N). This revised version was published online in June 2006 with corrections to the Cover Date.     

Aggregation of two different coordination polymers by reacting zinc nitrate and cadmium chloride with N,N′-ethylenebisacetamide

Two different coordination polymers are obtained from d¹⁰ metal ions [Zn(II) and Cd(II)] and N,N′-ethylenebisacetamide (EBA). {[Zn(EBA)_1.5(NO₃)]?·?(NO₃)} _n (1) is a 1-D coordination polymer assembled from zinc ions and EBA molecules acting as a bridging ligand. Cd(H₂O)₂Cl₂(EBA) (2) is constructed from 1-D inorganic polymeric chains {Cd(OH₂)₂Cl₂} _n and uncoordinated N,N′-ethylenebisacetamide molecules. These chains are interconnected through hydrogen bonds resulting in a 3-D supramolecular network. The luminescent properties of the organic molecule EBA, as well as of the coordination polymers 1, and 2 have been investigated.     

A NOVEL BINUCLEAR COPPER(II) COMPLEX: BIS[1,10-PHENANTHROLINE-N,N′-MALEATO- O,O′-COPPER(II)] DIMETHANOL TETRAHYDRATE

Abstract

A novel binuclear Cu(II) complex, [Cu₂(mal)₂(phen)₂]. 4H₂O. 2MeOH (phen= 1,10-phenanthroline, mal = maleato dianion), has been synthesized and characterized by elemental analysis, IR spectroscopy, solid-state ESR analysis and X-ray single crystal study. The complex consists of [Cu(mal)(phen)] subunits with two water and one methanol solvate molecules. The subunits show a distorted planar arrangement, existing in centrosymmetrically related pairs in the crystal packing. They have a distorted four-coordinate square-planar arrangement of N and O atoms about the central Cu atom; pairs of these [Cu(mal)(phen)] subunits form dimers by interaction of the fifth position on each Cu center with an O atom of a maleato ligand of the associated subunit with a Cu-Cu distance of 3.3425(9) å. The coordination around each Cu atom is best described as distorted square-pyramidal. The lattice water and methanol molecules are also confirmed by the TG study and IR spectra. The X-band solid-state ESR spectrum at room temperature exhibits an anisotropic feature with g′ = 2.24, g′ = 2.06.     

Synthesis and X-ray crystal structures of N,N,N′,N′-tetraalkylpyridine-2,6-dithiocarboxamides (S-dapt) complexes of cobalt(II) and nickel(II)

Reactions of anhydrous CoX₂ (X?=?Br^?, SCN^?) and Ni(ClO₄)₂ with N,N,N′,N′-tetraisobutylpyridine-2,6-dithiocarboxamides (S-dbpt), N,N,N′,N′-tetraisopropyl pyridine-2,6-dithiocarboxamides (S-dppt), and N,N,N′,N′-tetraethylpyridine-2,6-dithiocarboxamides (S-dept) lead to the formation of [Co(S-dbpt)Br₂] (1), [Co(S-dppt)(SCN)₂] (2), and [Ni(S-dept)₂]·(ClO₄)₂·H₂O (3), respectively. The X-ray crystal structures of the three S-dapt ligands and three complexes along with spectroscopic analyzes are presented. The molecular structure investigations of the S-dapt ligands show that the thiamide planes are twisted with respect to the pyridine ring, which is more in the case of phenyl groups. The structures of the Co(II) complexes reveal that an increase in steric crowding on the amide side arms of the ligands has no substantial effect on the geometry adopted by the corresponding complexes. The Co(II) gives only 1?:?1 five-coordinate, ion-paired complexes with a distorted square pyramidal geometry. Ni(II), on the other hand, prefers an octahedral geometry with 1?:?2 metal–ligand ratio. The coordination behavior of S-dapt has been compared to the analogous oxo(O-daap) ligands. Lesser propensity of S atom to get involved in H-bonding interactions ensures an S-N-S type of tridentate coordination by S-dapt.     

Synthesis and structural studies of (2E,3E)-3-[(6-{[(1E,2E)-2-(hydroxyimino)-1-methylpropylidene]amino}pyridin-2-yl)imino]butan-2-one oxime, ligand and its mono-, di- and trinuclear copper(II) complexes

A new dioxime ligand, (2E,3E)-3-[(6-{[(1E,2E)-2-(hydroxyimino)-1-methylpropylidene]amino}-pyridin-2-yl)imino]butan-2-one oxime, (H₂Pymdo) (3) has been synthesized in H₂O by reacting 2,3-butenedione monoxime (2) with 2,6-diaminopyridine. Mono-, di- and tri-nuclear copper(II) complexes of the dioxime ligand (H₂Pymdo) and/or 1,10-phenanthroline have been prepared. The dioxime ligand (H₂Pymdo) and its copper(II) complexes were characterized by ¹H-n.m.r., ¹³C-n.m.r. and elemental analyses, magnetic moments, i.r. and mass spectral studies. The mononuclear copper(II) complex of H₂Pymdo was found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). In the dinuclear complexes, in which the first Cu(II) ion was complexed with nitrogen atoms of the oxime and imine groups, the second Cu(II) ion is ligated with dianionic oxygen atoms of the oxime groups and are linked to the 1,10-phenanthroline nitrogen atoms. The trinuclear copper(II) complex (6) was formed by coordination of the third Cu(II) ion with dianionic oxygen atoms of each of two molecules of the mononuclear copper(II) complexes. The data support the proposed structure of H₂Pymdo and its Cu(II) complexes.     

Synthesis and characterization of manganese(II), nickel(II), copper(II) and zinc(II) Schiff-base complexes derived from 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-mercaptoethylamine

The synthesis of a new Schiff base containing 1,10-phenanthroline-2,9-dicarboxaldehyde and 2-mercaptoethylamine is described. The reaction of 1,10-phenanthroline-2,9-dicarboxaldehyde with 2-mercaptoethylamine leads to 2,9-bis(2-ethanthiazolinyl)-1,10-phenanthroline (I) which undergoes rearrangement when reacted with manganese, nickel, copper or zinc ions to produce complexes of the tautomeric Schiff base 2,9-bis[2-(2-mercaptoethyl)-2-azaethene]-1,10-phenanthroline (L). The [M(L)Cl₂] complexes [where M = Mn(II), Ni(II), Cu(II) and Zn(II) ions] were characterized by physical and spectroscopic measurements which indicated that the ligand is a tetradentate N₄ chelating agent.     

Towards understanding the correlation between UO<Subscript>2</Subscript><Superscript>2+</Superscript> extraction and substitute groups in 2,9-diamide-1,10-phenanthroline

2,9-Diamide-1,10-phenanthroline (DAPhen) ligands represent a new family of tetradentate extractants given their strong affinity to actinides and the CHON principle. Among this family, N,N′-diethyl-N,N′-ditolyl-2,9-diamide-1,10-phenanthroline (Et-Tol-DAPhen), initially reported by us, exhibits excellent selectivity towards actinides (U, Th, Am, Pu) over lanthanides and thus can be potentially applied in the group actinide extraction (GANEX) process for the group separation of actinides. In this article, by tailoring the lengths of alkyl chains, we synthesized other four DAPhen ligands with different substitute groups in the diamide moieties, and characterized the relationship between properties and substitute groups of DAPhen ligand. The extraction results show that three of the ligands exhibit high performance in UO₂²⁺ extraction from an acidic solution and the extracted UO₂²⁺ can be easily stripped by only using ultrapure water. Spectrophotometry titration confirms that UO₂²⁺ combined with all the four ligands in 1:1 mode. The extended X-ray absorption finestructure (EXAFS) study shows that six donor atoms comprise the first equatorial shell of the UO₂²⁺ ions bonded by the DAPhen ligands, among which two nitrogen and two oxygen atoms are from the DAPhen ligand, while other two oxygen atoms are from one nitrate ions. This article promises to provide basic data for assessing the feasibility of this kind of DAPhen ligands applied in actinides separation from nuclear wastes.     

Synthesis, spectroscopic, thermal, crystal characterization and biological activity of [Ni(phen)3][Ni(dipic)2]2.17H2O (H2dipic:pyridine-2,6-dicarboxylic acid, phen: 1,10-phenanthroline)

The new [Ni(phen)₃][Ni(dipic)₂]₂.17H₂O (1) (phen = 1,10-phenanthroline, dipic = dipicolinate)) has been prepared and characterized by elemental analysis, IR, UV-Vis, magnetic measurement and single crystal X-ray diffraction. The complex consists of two tris(1,10-phenanthroline)nickel(II) cations, two bis(dipicolinato)nickelate(II) anions and seventeen uncoordinated water molecules. The Ni(II) complex crystallizes in the triclinic space group P-1. The complex consisting of cation has distorted octahedral coordination by three bidentate phen ligands. In the complex anion, each dipic ligand simultaneously exhibits tridentate coordination modes through N atom of pyridine ring and oxygen atoms of the carboxylate groups. The crystal packing of 1 is a composite of intermolecular hydrogen bonding, π-π and C-H?π interactions. The complex has also been investigated in terms of biological activity and it showed high activity against S. aureus from Gram positive bacteria and C. albicans from yeast tested.     

Synthesis,structures, and characterization of cadmium(II), cobalt(II), and copper(II) metal polymers with tetrazole-1-acetate

Three new coordination polymers {[Cd(tza)(2,2′-bpy)(H₂O)](ClO₄)} _n 1, {[Co(tza)(2,2′-bpy)(H₂O)](ClO₄)} _n 2, and {[Cu(tza)(phen)](ClO₄)} _n 3 (Htza = tetrazole-1-acetic acid, 2,2′-bpy = 2,2′-bipyridyl, phen = 1,10-phenanthroline) were synthesized and characterized by X-ray single-crystal diffraction, elemental analysis, and IR spectra. Complexes 1 and 2 exhibit 3-D architectures formed by π–π interaction of 2,2′-bpy ligands interlinking to the adjacent 2-D layers. Complex 3 is a 1-D zigzag double chain and the 3-D structure is formed by π–π stacking interaction of phen and nonclassical hydrogen bonding.     

Efficient synthesis of a new ditopic bipyridine–terpyridine bridging ligand

Abstract

The novel bipyridine–terpyridine–phenazine ligand 6-pyrid-(tetrapyrido[2,3-a:2′,3′-c:3′′,2′′-h:2′′′,3′′′-j]phenazine (I) was prepared by condensation reaction of 5,6-diamino-l,10-phenanthroline (4) and 2-(pyrid-2′-yl)-1,10-phenanthroline-5,6-dione (6) and characterized using conventional methods. Poor solubility of the ligand led us to the preparation of its Ru(II) complexes to investigate the change in its solubility for further characterizing the ligand on the metal ion. [Ru(ttp)(I)](PF₆)₂ complex was prepared using the reaction of the ligand (I) and [Ru(ttp)Cl₃] complex, where ttp is 4′-(4-Methylphenyl)-2,2′:6′,2′′-terpyridine. A different route for the preparation of [Ru(ttp)(I)](PF₆)₂ was introduced. Synthesis of the ligand (I) on the complex by a condensation reaction of [Ru(ttp)(6)](PF₆)₂, where ligand (6) is 2-(pyrid-2′-yl)-1,10-phenanthroline-5,6-dione, with 5,6-diamino-l,10-phenanthroline (4) was conducted. The spectroscopic measurements of both products which have been obtained through the two different routes were compared. We observed that the NMR, LC-MS, and UV spectra of the both products were identical.