Organic-inorganic hybrid materials: Ligand influences on the structural chemistry of copper-vanadates

Hydrothermal reactions were used in the preparation of a series of bimetallic organic-inorganic hybrid materials of the M(II)/V_xO_y/organonitrogen ligand class. Compound 1, [{Cu₂(bpa)₂(C₂O₄)}₂V₄O₁₂]·H₂O, is molecular, while [{Cu(terpy)}₂V₆O₁₇] (2), [Cu₂(bpyrm)V₄O₁₂] (4) and [{Cu(phen)(H₂O)₂}VOF₄(H₂O)]·2H₂O (5) are two-dimensional, three-dimensional and one-dimensional, respectively (bpa = 2,2′-bipyridylamine; terpy = 2,2′:6,2″-terpyridine; bpyrm = 2,2′-bipyrimidine; phen = 1,10-phenanthroline). In contrast to the 2-D structure of 2, the Ni(II) analogue [{Ni(terpy)}₂V₄O₁₂]·2H₂O (3) is one-dimensional. The {V₄O₁₂}⁴⁻ cluster is a building block of structures 1, 3, and 4 while 2 is constructed from {V₆O₁₇}⁴⁻ rings.     

Organic-inorganic hybrid materials constructed from copper-organoimine subunits and molybdoarsonate clusters

The hydrothermal reactions of MoO₃, As₂O₅, Cu(CH₃CO₂)₂ · H₂O and an appropriate organonitrogen ligand in the presence of HF as mineralizer yield a series of bimetallic oxides of the Cu/Mo/O/As system. The compounds [{Cu₂(4,7-phen)(4,7-phenH)₂}Mo₁₂AsO₄₀] · 2.66H₂O (1 · 2.66H₂O) and [{Cu₃(qtpyr)₂}Mo₁₂AsO₄₀] · 0.4H₂O (2 · 0.4H₂O) (qtpyr = 2,4′:5′, 3″:4″,2?-quaterpyridine) are two-dimensional phases constructed from Keggin clusters linked through binuclear {Cu₂(4,7-phen)(4,7-Hphen)₂}²⁺ units in metal organic networks in 2. In contrast, the structure of [{Cu₂(2,4′-Hbpy)₄}Mo₁₈As₂O₆₂] · 2H₂O (3 · 2H₂O) is one-dimensional, consisting of Dawson clusters linked through binuclear {Cu₂(Hbpy)₄}⁶⁺ subunits. In the case of the compounds [{Cu(5,5′-dimethyl-2,2′-bpy)}₂Mo₂O₄F₂(AsO₄)₂] (4) and [{Cu(phen)}₂Mo₂O₄F₂(AsO₄)₂] (5), the fluoride mineralizer has been incorporated into the structure to give one-dimensional phases constructed from oxyfluoride {Mo₂O₄F₂(AsO₄)₂}²⁻clusters bridged through {Cu(organonitrogen)}²⁺ units.     

A family of titanium (IV) alkoxo complexes with N,O and O,O chelating ligands. Crystal structure of [Ti(O-i-Pr)2{2-(−)-menthoxo-pyridine}2]

In view of the wide applicability and versatility of titanium based Lewis acids in selective organic synthesis including asymmetric synthesis, we have synthesized a family of mono and polyatomic titanium derivatives. The polymetallic complexes prepared are bridged by pyridimine, quinone and triazine based ligands. The synthesis of [{Ti(O-i-Pr)₃(Oddbf)}₂] (1), [Ti(O-i-Pr)₂(Oddbf)₂] (2), [{Ti(O-i-Pr)₂(Oddbf)(OMent)}₂] (3) (ddbfO = 2,3-dihydro-2,2-dimethyl-benzofuranoxo; MentO = (1R,2S,5R)-(−)-menthoxo), [{Ti(O-i-Pr)₃(OMenpy)}₂] (4), [Ti(O-i-Pr)₂(OMenpy)₂] (5) (MenpyO = (1S,2S,5R)-(−)-menthoxo-pyridine); [{(Ti(OR)₃)₂L}_n] (RO = isopropoxo, (1R,2S,5R)-(−)-menthoxo) (6-11) and [{(Ti(O-i-Pr)₃)₃L}_n] (12) was accomplished from a Lewis acid such as Ti(O-i-Pr)₄, [{Ti(O-i-Pr)₃(OMent)}₂] or [Ti(OMent)₄] and chelating ligands (ddbfOH = 2,3-dihydro-2,2-dimethyl-benzofuranol; MenpyOH = (1R,2S,5R)-(−)-5-methyl-2-isopropyl-1-(2′-pyridinyl)cyclohexan-1-ol; LH₂ = 4,6-dihydroxy-2,5-diphenyl-pyrimidine, 2,4-dihydroxy-5,6-dimethyl-pyrimidine, 5,8-dihydroxy-1,4-napthoquinone, 2,5-dihydroxy-1,4-benzoquinone and LH₃ = cyanuric acid) that provide a rigid framework for the metal centre. The molecular structure of 5 has been determined by single crystal X-ray diffraction studies.     

Synthesis, crystal structure and luminescent behaviour of coordination complexes of copper with bi- and tridentate amines and phosphonic acids

The synthesis and crystal structure of four new copper(I) and copper(II) supramolecular amine, and amine phosphonate, complexes is reported. Reaction of copper(I) with 2-,9-dimethyl-1-10-phenanthroline (dmp) produced a stable 4-coordinate Cu(I) species, [Cu^(I)(dmp)₂]Cl · MeOH · 5H₂O (2), i.e., the increased steric hindrance in the ‘bite’ area of dmp did not prevent interaction with the metal and provided protection against oxidation which was not possible for the phen analogue [R. Clarke, K. Latham, C. Rix, M. Hobday, J. White, CrystEngCommun. 7(3) (2005), 28-36]. Subsequent addition of phenylphosphonic acid to (2) produced two structures from alternative synthetic routes. An ‘in situ’ process yielded red block Cu(I) crystals, [Cu^(I)(dmp)₂] · [C₆H₅PO₃H₂ · C₆H₅PO₃H] (4), whilst recrystallisation of (2) prior to addition of the acid (‘stepwise’ process) produced a green, needle-like Cu(II) complex, [Cu^(II)(dmp) · (H₂O)₂ · C₆H₅PO₂(OH)] [C₆H₅PO₂(OH)] (3). However, addition of excess dmp during the ‘stepwise’ process forced the equilibrium towards product (4) and resulted in an optimum yield (99%). The structure of (4) was similar to the phen analogue, [Cu^(II)Cl(phen)₂] · [C₆H₅PO₂(OH) · C₆H₅PO(OH)₂] (1) [R. Clarke, K. Latham, C. Rix, M. Hobday, J. White, CrystEngCommun. 7(3) (2005), 28-36], but the presence of dmp exerted some influence on global packing, whilst (3) exists as a polymeric layered material. In contrast, reaction of copper(I) with di-2-pyridyl ketone (dpk), followed by phenylphosphonic acid produced purple/blue Cu(II) species, [Cu^(II)(dpk · H₂O)₂] Cl₂ · 4H₂O (5), and [Cu^(II)(dpk · H₂O)₂] · [C₆H₅PO₂(OH)₂ · C₆H₅PO(OH)₂] (6), respectively, i.e., in both cases oxidation of copper occurred. Solid-state luminescence was observed in (2) and (4). The latter showing a 5-fold enhancement in intensity.     

Two copper complexes based on ligand bearing ferrocene unit: Synthesis and structural characterization

The reaction of [(2-Pyridylmethylamino)carbonyl]ferrocene with Cu(ClO₄)₂ · 6H₂O under conventional condition in the absence of base affords a monocopper compound, [Cu(Hpmaf)₂(CH₃OH)₂](ClO₄)₂] 1, while that under solvothermal condition in the presence of triethylamine gives a dicopper compound, [Cu₂(pmaf)₂](ClO₄) 2, (Hpmaf = [(2-Pyridylmethylamino)carbonyl]ferrocene). Both compounds were characterised by elemental analysis, IR and X-ray diffraction analysis. Compound 2 was further characterised by UV-vis and electron paramagnetic resonance (EPR), and the results indicate that it is a fully delocalised mixed-valence dicopper compound. This is the first example of mixed-valence dicopper compound containing ferrocene group.     

Synthesis and crystal structure of a cis-oxime-oximate bridged tetra coordinated open-book shaped new dicopper(II/II) complex [Cu2(μ-Hdmg)2(Hdmg)]ClO4: First report of unusual oxime OH bridging

Reaction of Cu(ClO₄)₂ · 6H₂O with dimethylglyoxime (H₂dmg) and triethylamine (pH ∼ 4-5) at room temperature affords oxime bridged dicopper(II/II) complex of formula [Cu₂(μ-Hdmg)₂(Hdmg)]ClO₄ · H₂O (1) (H₂dmg = dimethylglyoxime). The complex has been characterized by single-crystal X-ray diffraction analysis. The structure consists of one dinuclear complex cation, [Cu₂(μ-Hdmg)₂(Hdmg)], and one anion. Two copper(II) ions at a distance of 3.558 Å are bridged by one oxime and one oximate groups in cis arrangement. The geometry around each copper atom is square planar with an overall open-book type arrangement of these planes. The average copper-oxygen distance is (1.953 Å) and the average copper-nitrogen distance is 2.003 Å. The Cu-O(oxime) distance (1.963 Å) is higher than the Cu-O(oximate) distance (1.942 Å) due to different protonation label. The room temperature value of χ_MT for the title complex (χ_M being the molar magnetic susceptibility for two copper atoms) is low (ca. 0.42 cm³ K mol⁻¹) (μ_eff = 1.52 μ_B). The UV-Vis spectrum of the complex shows a characteristic broad band at 470 nm.     

Trinuclear copper(II) complexes of bis(acylhydrazone) ligands. Structural analysis and magnetic properties of a sulfato-bridged hexanuclear dimer

The synthesis and spectroscopic characterization of the new symmetric, ligand bis(salicylaldehyde)methyliminodiacetylhydrazone (H₄MeImds) is reported. The reactions of H₄ MeImds with copper(II) chloride, nitrate and sulfate give trinuclear metal complexes of formula Cu₃(MeImds)Cl₂ · CHCl₃ · H₂O, Cu₃(MeImds)(NO₃)₂ · 2H₂O and Cu₃(MeImds)(SO₄) · 8H₂O; the trinuclear species are obtained in spite of the used metal:ligand molar ratio. The X-ray crystal structure of [Cu₃(MeImds)(SO₄)(H₂O)₃] · 5H₂O is determined; it consists of linear units, with the nonadentate ligand bound to three copper ions. The trimetallic units are bridged via sulfate anions to give hexanuclear dimers with an imposed centre of symmetry. The magnetic properties of [Cu₃(MeImds)(SO₄)(H₂O)₃] · 5H₂O are characterized by a significant antiferromagnetic coupling within the trimetallic units and by a weak antiferromagnetic coupling between them. The analogous trinuclear copper(II) complexes Cu₃(HImds)Cl₂ · H₂O and Cu₃(HImds)(SO₄) · 4H₂O (H₅Imds, bis(salicylaldehyde)iminodiacetylhydrazone) were also prepared and spectroscopically characterized.     

Diverse coordination of polynuclear copper(II) complexes constructed from benzene tetracarboxylates

The reaction of aqueous solutions of the preformed 1:1 Cu(ClO₄)₂-polydentate amine with tetrasodium 1,2,4,5-benzene tetracarboxylate (Na₄bta) afforded three different types of polynuclear compounds. These include the tetranuclear complexes: [Cu₄(Medpt)₄(μ₄-bta)(ClO₄)₂(H₂O)₂](ClO₄)₂·2H₂O (1), [Cu₄(pmdien)₄(μ₄-bta)(H₂O)₄](ClO₄)₄ (2), [Cu₄(Mepea)₄(μ₄-bta)(H₂O)₂](ClO₄)₄(3), [Cu₄(TPA)₄(μ₄-bta)](ClO₄)₄·10H₂O (4) and [Cu₄(tepa)₄(μ₄-bta)](ClO₄)₄·2H₂O (5), the di-nuclear: [Cu₂(DPA)₂(μ₂-bta)(H₂O)₂]·4H₂O (6), [Cu₂(dppa)₂(μ₂-bta)(H₂O)₂]·4H₂O (7) and [Cu₂(pmea)₂(μ₂-bta)]·14H₂O (8) and the trinuclear complex [Cu₃(dppa)₃(μ₃-bta)(H₂O)_2.25](ClO₄)₂·6.5H₂O (9) where Medpt = 3,3′-diamino-N-methyldipropylamine, pmedien = N,N,N′,N″,N″-pentamethyldiethylenetriamine, Mepea = [2-(2-pyridyl)ethyl]-(2-pyridylmethyl)methylamine, TPA = tris(2-pyridylmethyl)amine, tepa = tris[2-(2-pyridyl)ethyl)]amine, DPA = di(2-pyridymethyl)amine, dppa = N-propanamide-bis(2-pyridylmethyl)amine and pmea = bis(2-pyridylmethyl)-[2-(2-pyridylethyl)]amine. The complexes were structurally characterized by elemental analyses, spectroscopic techniques, and by X-ray crystallography for complexes 1, 2, 4, 6, 7 and 9. X-ray structure of the complexes reveal that bta⁴⁻ is acting as a bridging ligand via its four deprotonated caboxylate groups in 1, 2 and 4, three carboxylate groups in 9 and via two trans-carboxylates in 6 and 7. The complexes exhibit extended supramolecular networks with different dimensionality: 1-D in 2 and 4 due to hydrogen bonds of the type O-H···O, 2-D in 1 and 7, and 3-D network in 6 as a result of hydrogen bonds of the types N-H···O and O-H···O. Magnetic susceptibility measurements showed very weak antiferromagnetic coupling between the Cu^II ions in 1-5, 7-9 (|J| = 0.02-0.87 cm⁻¹) and weak ferromagnetic coupling for 6 (J = 0.08 cm⁻¹).     

Syntheses, structures and properties of copper(II) complexes containing N-(2-hydroxybenzyl)-amino amide ligands

Four copper(II) complexes containing the reduced Schiff base ligands, namely, N-(2-hydroxybenzyl)-glycinamide (Hsglym) and N-(2-hydroxybenzyl)-l-alaninamide (Hsalam) have been synthesized and characterized. The crystal structures of [Cu₂(sglym)₂Cl₂] (1), [Cu₂(salam)₂(NO₃)₂] · H₂O (3), [Cu₂(salam)₂(NO₃)(H₂O)](NO₃) · 1.5H₂O (4), [Cu₂(salam)₂](ClO₄)₂ · 2H₂O (5) show that the Cu(II) atoms are bridged by two phenolato oxygen atoms in the dimers. The sglym ligand bonded to Cu(II) in facial manner while salam ligand prefers to bind to Cu(II) in meridonal geometry. Variable temperature magnetic studies of 3 showed it is antiferromagnetic. These Cu(II) complexes and [Cu₂(sglym)₂(NO₃)₂] (2), exhibit very small catecholase activity as compared to the corresponding complexes containing acid functional groups.     

Insertion reactions of organic anhydrides and the Cu(I) alkoxide [CuOBu]

The synthesis and structural characterization of the copper salts [Cu₈(benzoate)₈(THF)₆] (1), [Cu₂{(CO₂)₂C₆H₂(Boc)₂}dppm₂]₂ (2) and [Cu₂{(CO₂)₂C₁₀H₄(Boc)₂}dppm₂]₂ (3) [Boc = tert-butoxycarbonyl, dppm = 1,2-bis(diphenylphosphino)methane] prove that cyclic organic anhydrides and dianhydrides readily insert into the Cu-O bond of [CuO^tBu] forming carboxylate ligands with ester functionalities in the ligand periphery. [Mn₃(o-Boc-benzoate)₆(DME)₂] (4) (DME = 1,2-dimethoxyethane) was synthesized by the metathesis reaction of [Cu(I)(o-Boc-benzoate)] with MnCl₂.     

Two new extended frameworks constructed from the sandwiching polytungstoarsenate clusters

Two new extended frameworks based on two different sandwich-type polytungstoarsenates have been synthesized under routine conditions. The reaction of Na₉[As^IIIW₉O₃₃]·19.5H₂O, MnSO₄·H₂O and citric acid in a weak acidic aqueous solution at pH = 4.23 led to the isolation of a new extended sandwich-type compound {K₃Na₈[{Mn^II(H₂O)}_2.5{(WO)(H₂O)}_0.5(AsW₉O₃₃)₂]·12.5H₂O}_n (1). In compound 1, each sandwiching polyoxoanion [{Mn^II(H₂O)}_2.5{(WO)(H₂O)}_0.5(AsW₉O₃₃)₂]¹¹⁻ acts as a quadridentate ligand to connect with four neighbors via the mode of {W-O-Mn}, finally leading to an interesting 2D network. The reaction of Na₈[HAsW₉O₃₄]·11H₂O, CeCl₃·7H₂O and hexamethylenetetramine in an aqueous solution with pH = 5.07 resulted in the obtainment of a polytungstoarsenate-based extended compound [HMTA-CH₃]₂[HMTA]K₂Na₇[Ce(AsW₁₁O₃₉)₂]·19H₂O(2) (HMTA-CH₃ = methyl-hexamethylenetetraamine; HMTA = hexamethylenetetraamine). In 2, the polyoxoanions [Ce(AsW₁₁O₃₉)₂]¹¹⁻ construct a new extended structure through coordinating to the {KO₅(H₂O)[HMTA-CH₃]} and {KO₄(H₂O)₂[HMTA]} units. The two compounds are characterized by elemental analyses, IR, the diffuse reflectance UV-Vis spectra, PXRD and TG analyses. The electrochemical and electrocatalytical properties of 1 and 2, as well as the fluorescent property of 2 were also investigated.     

Three new multidimensional organic-inorganic hybrids based on polyoxometalates and copper coordination polymers with 4,4′-bipyridine ligands

Three new organic-inorganic hybrid materials with 4,4′-bipy ligands and copper cations as linkers, [Cu^II(H₂O)(4,4′-bipy)₂][Cu^II(H₂O)(4,4′-bpy)₂]₂H[Cu^IIP₈Mo₁₂O₆₂H₁₂] · 5H₂O (1), [Cu^I(4,4′-bipy)][Cu^II(4,4′-bipy)]₂ (BW₁₂O₄₀) · (4,4′-bipy) · 2H₂O (2) and [Cu^I (4,4′-bipy)]₃ (PMo₁₂O₄₀) · (pip) · 2H₂O (3) (pip = piperazine; 4,4′-bipy = 4,4′-bipyridine), have been hydrothermally synthesized. The single X-ray structural analysis reveals that the structure of 1 is constructed from [Cu(H₂O)(4,4′-bipy)₂] complexes into a novel, three-dimensional supermolecular network with 1-D channels in which Cu[P₄Mo₆]₂ dimer clusters reside. To the best of our knowledge, compound 1 is the first complex in which the [P₄Mo₆] clusters have been used as a non-coordinating anionic template for the construction of a novel, three-dimensional supermolecular network. Compound 2 is constructed from the six-supported [BW₁₂O₄₀]⁵⁻ polyoxoanions and [Cu^I(4,4′-bipy)] and [Cu^II(4,4′-bipy)] groups into a novel, 3-D network. Compound 3 exhibits unusual 3-D supramolecular frameworks, which are constructed from tetrasupporting [PMo₁₂O₄₀]³⁻ clusters and [Cu^I (4,4′-bipy)_n] coordination polymer chains. The electrochemical properties of 2 and 3 have been investigated in detail.     

Hydrothermal syntheses and characterizations of 0D to 3D polyoxotungstates linked by copper ions

A new family of hybrid organic-inorganic materials built from polyoxotungstates and Cu(II) ions as linkers has been synthesized by hydrothermal reactions from a mixture of sodium tungstate, copper chloride and ethylenediamine. The initial pH and the presence or absence of heteroelement (P, Si) control the nature of the polyoxotungstate clusters and their connectivity via the copper ions, and hence the dimensionality of the framework. In the absence of heteroelement, three compounds have been isolated: at low pH (5) the molecular compound [Cu(en)₂(H₂O)]₂[{Cu(en)₂}H₂W₁₂O₄₀] · 10H₂O (1) is formed, at neutral pH the 3D material [{Cu(en)₂}₃{Cu(en)}₂H₂W₁₂O₄₂] · 27H₂O (2) and at high pH (11) the 2D compound [Cu(en)₂(H₂O)₂][Cu(en)₂][{Cu(en)₂}₃H₂W₁₂O₄₂] · 15H₂O (3). In the whole range of pH (5-11.5) a single phase has been obtained with silicium as heteroelement, namely the 2D material [Cu(en)₂(H₂O)][{Cu(en)₂}₂SiW₁₁CuO₃₉] · 7H₂O (4) with chains of Keggin polyoxotungstates linked by {Cu(en)₂}²⁺ groups. Finally, a phosphotungstate with a chain-like structure has been characterized, [{Cu(en)₂}₃PW₁₁CuClO₃₉] · 6H₂O (5), at low pH (5) which differs from the phase obtained at higher pH.     

Preparation and structures of the cluster dimers consisting of Rh2Mo2S4 single-cubane units connected by two bidentate N-donor ligands

Reactions of a single-cubane cluster [{Rh(cod)}₂{MoCl(dtc)}₂(μ₃-S)₄] (cod = 1,5-cyclooctadiene, dtc = diethyldithiocarbamate) with 1 equiv. of L (L = pyrazine, 4,4′-bipyridyl, trans-1,2-bis(4-pyridyl)ethylene) in the presence of 2 equiv. of AgBF₄ in CH₂Cl₂ gave doubly bridged double-cubane clusters [({Rh(cod)}₂{Mo(dtc)}₂(μ₃-S)₄)₂(μ-L)₂][BF₄]₄, whose structures were determined by the single-crystal X-ray analysis.     

Dinuclear ruthenium sawhorse-type complexes containing bridging ligands with ferrocenyl substituents in endo/endo, endo/exo and exo/exo orientations

The dinuclear ruthenium complexes Ru₂(CO)₄(OOCC₅H₄FeC₅H₅)₂L₂ (L = NC₅H₅: 1, L = PPh₃: 2) have been synthesized from Ru₃(CO)₁₂, ferrocene carboxylic acid and pyridine or triphenylphosphine, respectively. The single-crystal X-ray structure analysis reveals for 1 and 2 a Ru₂(CO)₄ sawhorse backbone with the two ferrocenyl substituents of the two carboxylato bridges being endo/exo with respect to each other in the solid state. With the new pyridine derivative NC₅H₄OOCC₅H₄FeC₅H₅ (4-ferrocenoyl pyridine) (3) as axial ligand, the complex Ru₂(CO)₄(OOCC₅H₄FeC₅H₅)₂(NC₅H₄OOCC₅H₄FeC₅H₅)₂ (4) was obtained, the single crystal X-ray structure analysis showing an exo/exo orientation of the two carboxylato bridges in the solid state. The endo/endo orientation is found in the solid-state structure of Ru₂(CO)₄(HNOCC₅H₄FeC₅H₅)₂(PPh₃)₂ (5), the two OCNH bridges being transoïd with respect to each other; this complex is accessible from Ru₃(CO)₁₂, ferrocenamide and triphenylphosphine.     

Hydroxylation of isophthalic acid in the hydrothermal reaction of Cu-isophthalate system - Syntheses and crystal structures of two coordination polymers

The reaction of isophthalic acid (H₂ip) and copper nitrate under hydrothermal condition produced an in situ synthesized ligand 2-hydroxy isophthalic acid (or 2,6-dicarboxyl phenol, H₃ipO) derived from H₂ip without the presence of N-heterocyclic ligands. The hydroxylation was controlled by the temperature of hydrothermal synthesis. Two coordination polymers, {[Cu₅(OH)₂(ip)(ipO)₂] · (H₂O)}_n (1) and [Cu₃(ipO)₂(H₂O)₂]_n (2) were synthesized and characterized by X-ray crystallography, IR spectra and elemental analyses. Complex 1 was assembled with both the original ligand and the in situ synthesized ligand.     

Two forms of a copper(II) complex of 3-phenyl-5-(2-pyridyl)-4-(4-pyridyl)-4H-1,2,4-triazole: a six-coordinate monomer versus a five-coordinate polymer

The reaction of the new bidirectional ligand 3-phenyl-5-(2-pyridyl)-4-(4-pyridyl)-4H-1,2,4-triazole (pyppt) with Cu(ClO₄)₂ · 6H₂O in a 2:1 molar ratio in EtOH affords the complex [Cu^II(pyppt)₂(ClO₄)₂] · H₂O (1) as a microcrystalline turquoise solid. Recrystallisation of complex 1 from MeCN by vapour diffusion of Et₂O gives blue crystals of the monomeric octahedral complex [Cu^II(pyppt)₂(ClO₄)₂] · MeCN (2). In contrast, addition of EtOH to a solution of complex 1 in MeCN followed by slow evaporation yields blue crystals of the five-coordinate polymeric complex {[Cu^II(pyppt)₂](ClO₄)₂ · EtOH}_∞ (3). The structures of both complexes have been determined by single crystal X-ray diffraction.     

New yttrium(III) and copper(II) coordination polymers with partially protonated cyclohexane-1,2,3,4,5,6-hexacarboxylato ligands: Synthesis, crystal structures and properties

Two coordination polymers, [Y(H₂O)₄(H₃chhc)]·6H₂O (1) and [Cu₅(H₂O)₁₀(Hchhc)₂]·4H₂O (2) with H₆chhc = cyclohexane-1,2,3,4,5,6-hexacarboxylic acid) represent rare examples of metal complexes with partially protonated cyclohexane-1,2,3,4,5,6-hexacarboxylato ligands. The [Y(H₂O)₄]³⁺ units in 1 are interlinked by the triprotonated (H₃chhc)³⁻ anions in a η⁵μ₄ bridging mode to form 2D (4³)₂(4⁶·6⁶·8³) topological networks, which are stacked along [0 1 0] direction in ···ABAB··· fashion with the lattice H₂O molecules sandwiched between layers. The pentameric [Cu₅(H₂O)₁₀]¹⁰⁺ units in 2 are bridged by monoprotonated (Hchhc)⁵⁻ anions in a η⁸μ₆ fashion to generate a 3D MOF of an unprecendented (4³)(4⁵·6⁷·8³) topology with the lattice H₂O molecules in channels. The temperature-dependent magnetic susceptibility data of 2 could be modeled to a combination of a linear chain of equally-spaced Cu(II) ions (J₁ = 1.86 cm⁻¹) with an isosceles triangular Cu₃ unit (J₂ = 5.86 cm⁻¹).     

Synthesis,structures and reactivity of N-donor-functionalised Cu(I) aryloxides

The preparation and characterisation of the Cu(I) aryloxides [Cu₁₆(3-pyO)₁₆(dppm)₈] (1), [{Cu₂(2-pyO)₂(dppm)}₂] (2) and [{Cu₃(μ₃-6-OQ)₂(dppm)₃}{(6-HOQ)₂(μ-6-OQ)}] (3) (dppm = 1,2-bis-diphenylphosphinomethane, 6-HOQ = 6-hydroxyquinoline, py = pyridine) are described. A first attempt to employ organic anhydrides in insertion reactions with Cu(I) aryloxides was made producing the one-dimensional coordination polymer 1/_∞[Cu₃(3-pyO)(CO₂C₂H₄Boc)(dppm⁻)(dppm)]_∞ (4) (Boc = tert-butoxycarbonyl).     

Insertion reactions of organic anhydrides into the M-O bond of CuOBu and Sb(OMe)3

The synthesis and structural characterization of the copper salts [Cu₂(2-Boc-benzoate)₄(dme)₂] (1), [Cu(2-Boc-benzoate)₂(tmeda)] (2), [Cu₂(2-Boc-benzoate)₂(dppm)] (3), [Cu(2-Boc-nicotinate)(PPh₃)₂] (4), [Cu₂{2-Boc-5,6-anhydride-naphthylcarboxylate}₂(dppm)₂] (5) [dme = 1,2-dimethoxyethane, dppm = bis(diphenylphosphino)methane, tmeda = N,N′-tetramethylethylenediamine, Boc = tert-butoxycarbonyl] prove that cyclic organic anhydrides and dianhydrides readily insert into the Cu-O bond of [CuO^tBu] forming carboxylate ligands with ester functionalities in the ligand periphery. [Sb(CO₂Ph-o-CO₂Me)₂(OMe)(tmeda)] (6) was synthesised by insertion reaction of Sb(OMe)₃ with phthalic anhydride.