Structural Modulation of Coordination Polymers by Heterometallic Approach

A series of heterometallic Ni^II/Co^II coordination polymers with 2D networks were synthesized by tetrazole‐1‐acetate ligands and structurally characterized. With increasing concentration of cobalt(II), another different connectivity patterns have been observed. The influence of cobalt(II) is not only on the crystallization, but also on the variation of magnetic properties.     

Assembly and packing models of [Ti6Co12] ring based on the titanium-capped cobalt clathrochelates

In this work, titanium-capped cobalt clathrochelates have been applied as secondary building units (SBUs) for the construction of supramolecular rings. Two heterometallic wheel-like [Ti₆Co₁₂] complexes based on cobalt clathrochelates, [C₆H₁₅N₄]₂[TiCo₂(μ₂-Oipr)(Oipr)₂(Dmg)₃]₆ (2, Dmg = dimethylglyoxime) and H₆[TiCo₂(μ₂-Oipr)(Oipr)₂(Dmg)₃]₆ (3), have been successfully synthesized and characterized. The supramolecular stacking modes of these wheels are largely dependent on the applied synthetic conditions, which further impact their gas adsorption properties.     

Reactivity of the unsaturated dimolybdenum anion [Mo2(η-C5H5)2(μ-PCy2)(μ-CO)2] towards electrophiles based on p- and d-block elements

The 30-electron binuclear anion [Mo₂Cp₂(μ-PCy₂)(μ-CO)₂]⁻ reacts with the chlorophosphite ClP(OEt)₂ or the organotin chlorides Cl₂SnPh₂ or ClSnPh₃ to give compounds of the formula trans-[Mo₂Cp₂(μ-E)(μ-PCy₂)(CO)₂], (E = P(OEt)₂, SnPh₃, SnPh₂Cl). In contrast, this anion reacts with the organosilicon chlorides ClSiR₃ (R = Ph, Me) to give unstable silyloxycarbyne-bridged complexes [Mo₂Cp₂(μ-PCy₂)(μ-COSiR₃)(μ-CO)], which rapidly hydrolyze to give the known hydride [Mo₂Cp₂(μ-H)(μ-PCy₂)(CO)₂]. Two main types of products were also observed in the reactions of the title anion with different chlorocomplexes of the transition and post-transition metals. Thus, the reactions with [MCl₂Cp₂] (M = Ti, Zr) give moisture-sensitive isocarbonyl-bridged complexes of the type [Mo₂Cp₂(μ-COMClCp₂)(μ-PCy₂)(μ-CO)]. In contrast, softer metallic electrophiles such as [AuCl(PR₃)] (R = ⁱPr, ptol) react with the anion at the dimolybdenum site to form new trimetallic clusters of the formula [AuMo₂Cp₂(μ-PCy₂)(CO)₂(PR₃)], also retaining a Mo−Mo triple bond. Subsequent reactions of the latter products with the solvate complexes [Au(PR₃)(THF)][PF₆] give the tetranuclear clusters [Au₂Mo₂Cp₂(μ-PCy₂)(CO)₂(PR₃)₂][PF₆] (Mo−Mo = 2.5674(3) Å and Au−Au = 2.7832(2) Å when R = ⁱPr). Finally, the reaction of the title anion with HgI₂ gives the pentanuclear cluster [Hg{Mo₂Cp₂(μ-PCy₂)(CO)₂}₂] or the trinuclear cluster [Mo₂Cp₂(μ-HgI)(μ-PCy₂)(CO)₂] depending on the stoichiometry being actually used for the reaction. The trinuclear species is only stable in tetrahydrofuran (THF), and decomposes to give a mixture of the dimeric species [Mo₂Cp₂(μ-HgI)(μ-PCy₂)(CO)₂]₂ along with variable amounts of the known iodide-bridged complex [Mo₂Cp₂(μ-I)(μ-PCy₂)(CO)₂].     

Heterometallic M/Mn (M=Cu, Co, Zn) acetate complexes as precursors for binary oxides

A facile one-pot procedure, or so-called “direct synthesis,” was used to prepare the novel heterometallic complexes [M₂Mn(OAc)₆(bpy)₂], where M=Cu (1), Co (2), Zn (3), bpy=2,2′-bipyridyl, with high yields via oxidative dissolution of pure metals in a liquid phase. The complexes were characterized by an elemental analysis, single crystal X-ray diffraction method and FTIR. These complexes are proposed as precursors, whose thermal degradation may lead to the formation of solids possessing nano- to microsize levels of dispersity. The thermal behavior of the complexes obtained was studied by thermal analysis (TG/DTA/DTG) in both air and N₂ and also by TPD mass-spectrometry in vacuo. The FTIR, X-ray powder diffraction (PXRD) and thermoanalytical data were used for the identification of the solid products of thermal degradation. The morphology and microstructure of the solid residues were analyzed, using scanning electron microscopy with energy dispersive X-ray microanalysis (SEM/EDX) at mkm and sub-micro levels.     

Coordination polymer [Li2Co2(Piv)6(μ-L)2]n (L = 2-amino-5-methylpyridine) as a new molecular precursor for LiCoO2 cathode material

The solid-state thermolysis (420–450 °С) of the new heterometallic coordination polymer [Li₂Co₂(Piv)₆(μ-L)₂]_n (1, Piv is the anion of pivalic acid, L is 2-amino-5-methylpyridine) followed by annealing of the decomposition products at 500 °С was shown to afford LiCoO₂ in quantitative yield. Compound 1 was characterized by X-ray diffraction and magnetic measurements.     

Construction of optically active multimetallic systems of rhodium(I), palladium(II), and ruthenium(II) with a P-chiral tetraphosphine ligand

The treatment of optically P-chiral tetraphosphine, (3S,6R,9R,12S)-6,9-di-tert-butyl-2,2,3,12,13,13-hexamethyl-3,6,9,12-tetraphosphatetradecane (1), with rhodium(I), palladium(II), and ruthenium(II) complex precursors led to the selective formation of mono-, di-, or trinuclear homo- or heterometallic complexes, [Rh(1)]SbF₆ (4), [{Rh(nbd)}₂(1)](SbF₆)₂ (3), [{Pd(η³-allyl)}₂(1)](SbF₆)₂ (5), [{RuCl(η⁵-C₅(CH₃)₅)}₂(1)] (6), and [{RuCl₂(η⁶-benzene)}₂(PdCl₂)(1)] (8). These complexes were characterized by NMR and X-ray crystallographic analysis.     

Two 1D Ladderlike Heterometallic Zinc(II) Coordination Polymers: Syntheses,Crystal Structures,and Fluorescence Properties

Two coordination polymers [Zn₂(ipt)₂(CuL)₂(H₂O)] ( 1 ) and [Zn₂(ipt)₂(NiL)₂(H₂O)] ( 2 ) (ML, H₂L = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclo‐pentadeca‐7,13‐dien; H₂ipt = isophthalic acid) were synthesized by solvothermal methods and characterized by single‐crystal X‐ray diffraction. Complexes 1 and 2 exhibit ladderlike chains, consisting of Zn₄Cu₄ and Zn₄Ni₄ units, respectively, which are connected via oxamide and isophthalate. These chains are further interlinked by hydrogen bonds resulting in a 2D supramolecular architecture. The fluorescence properties of compounds 1 and 2 are also discussed.     

Tetrazoleacetic acid templated 3d-4f heterometallic-organic frameworks constructed from different ligands: structures,luminescence, magnetism and photocatalytic properties

A series of 3-D lanthanide-transition 3d-4f heterometallic complexes have been synthesized by hydrothermal route from mixtures of 2,2′-bipyridyl-5,5′-dicarboxylic acid (H₂bpdc) and acetic acid (HAc) with tetrazoleacetic acid as template. The single-crystal X-ray analysis shows that nine CdLn(H₂O)₂Cl₂(bpdc)Ac complexes (Ln = La for 1, Pr for 2, Nd for 3, Sm for 4, Eu for 5, Gd for 6, Dy for 7, Ho for 8, Er for 9) crystallized in the space group P-1 and featured three-nodal (3, 4, 6)-three connected topological frameworks. The photocatalytic behaviors imply that 1–9 have significant photocatalytic activities for degradation of RhB.     

Syntheses and structures of 3d–4d heterometallic coordination polymers based on 4-amino-1,2,4-triazole

Three heterometallic coordination polymers based on 4-amino-1,2,4-triazole (atrz), Cd_2.98Fe_2.02(atrz)₆(SCN)₁₀·2H₂O (1), Cd_2.86Co_2.14(atrz)₆(SCN)₁₀·2H₂O (2), and Cd_2.02Ni_2.98(atrz)₆(SCN)₁₀·2H₂O (3), were synthesized. Crystal structures of the polymers were determined by single-crystal X-ray diffraction, X-ray powder diffraction, and infrared analysis. The complexes exhibit a 3-D structure and are isostructural, but entail different durations for transformation from a 1-D polymer to a 3-D structure. The results of vibrating sample magnetometry for 1 indicate that the complex exhibits weak paramagnetism.     

Sorption Behavior and Magnetic Properties of A Heterometallic Organic Framework with Octahedral Cages and One‐Dimensional Channels

The Zn^II‐Co^II organic framework [Me₂NH₂][Zn₂Co(μ₃‐OH)(BTC)₂(H₂O)] · 2H₂O ( FJI‐6 ) (H₃BTC = 1, 3,5‐benzenetricarboxylic acid and DMA = N.N′‐dimethyl acetamide), was synthesized and structurally characterized. FJI‐6 shows a three‐dimensional heterometallic microporous framework with coexisting octahedral cages and one‐dimensional channels assembled by Zn₂Co(μ₃‐OH)(CO₂)₆ secondary building units. In addition, the sorption behavior and magnetic properties of FJI‐6 were investigated.