Bis(saccharinato)copper(II) complexes with 2-aminomethylpyridine and 2-aminoethylpyridine: Syntheses,crystal structures,spectral and thermal characterizations of trans-[Cu(sac)2(ampy)2] and [Cu(sac)2(aepy)(H2O)] (ampy = 2-aminomethylpyridine and aepy = 2-aminoethylpyridine)

Two bis(saccharinato)copper(II) complexes with 2-aminomethylpyridine (ampy) and 2-aminoethylpyridine (aepy) have been prepared and characterized by elemental analyses, IR and electronic spectroscopy, magnetic measurements and single-crystal X-ray diffraction. The copper(II) ion in trans-[Cu(sac)₂(ampy)₂] has ?1 site symmetry and is octahedrally coordinated by two neutral ampy and two anionic sac ligands, whereas the copper(II) ion in [Cu(sac)₂(aepy)(H₂O)] is five-coordinate with a distorted square-pyramidal coordination geometry. Both ampy and aepy behave as bidentate (N,N′) chelating ligands, while the saccharinate anion (sac) in the title complexes is N-coordinated. IR spectra of both complexes display typical absorption bands of bidentate aminopyridines and N-bonded sac ligands. Thermal decomposition behavior of the complexes is described in detail.     

The synthesis and crystal structure of two new isopolyoxoanion complexes: [M2(DMF)12(Mo6O19)2] (M = Co,Ni, DMF = dimethylformamide)

Two solid-state materials,?{M₂(DMF)₁₂[Mo₆O₁₉]₂}?(M?=?Co, Ni, DMF?=?dimethylformamide), have been designed, synthesized under mild reaction conditions and characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. The structures exhibit extended 2D networks through hydrogen bonds among polyanions and [M(DMF)₆]²⁺; hydrogen-bonding interactions are responsible for the stability of the crystal.     

Transition metal salts of quinoline: synthesis,structure and magnetic behavior of (QuinH)2[MX4]·2H2O [Quin = quinoline; M = Mn,Co, Cu,Zn], (QuinH)2[MnBr2(H2O)2](Br)2 and (QuinH)[Cu(Quin)Br3]

Abstract

A family of compounds of general formula (QuinH)₂MX₄·2H₂O has been prepared and characterized [Quin?=?quinoline; M, X?=?Co,Cl (1); M, X?=?Co,Br (2); M, X?=?Zn,Br (3); M, X?=?Mn,Cl (4)]. The complexes crystallize in the monoclinic space group C2/c as well-isolated layers containing the MX₄^?2 anions and water molecules, separated by the quinolinium cations. The bromide analogue of 4, compound 5 (QuinH)₂[MnBr₂(H₂O)₂](Br)₂, also crystallizes in the C2/c space group, but comprises a co-crystal of manganese bromide dihydrate and quinolinium bromide. The temperature dependent magnetic properties of the complexes are described, along with the tetrachlorocuprate analogue (7). All compounds show weak antiferromagnetic interactions (J/k_B?～?0.06–1.4 K) and good one- or two-dimensional isolation. In addition, the crystal structure of the mixed quinoline/quinolinium complex (QuinH)[Cu(Quin)Br₃] (triclinic, P-1) is reported.     

Synthesis,structure, and electrochemical properties of [M(N-MeIm)6]2+ (M = Ni,Co, Cu) associated with [HgCl4]2−

Reaction of Hg(NO₃)₂ with 4 equivalent KI in water afford K₂[HgI₄]. By using K₂[HgI₄] as the precursor, three new heterobimetallic compounds [Ni(N-MeIm)₆][HgI₄] (I), [Co(N-MeIm)₆][HgI₄] (II), and [Cu(N-MeIm)₆][HgI₄] (III) have been characterized by elemental analysis, IR spectra, and the singlecrystal X-ray crystallorgraphy analysis. Three complexes are isomorphous and crystallized in monoclinic symmetry space group P2₁/c. The coordination around each center metal(II) atom is octahedral with six nitrogen atoms of N-MeIm ligand. Each structure contains one tetrahedral [HgI₄]^2? as an anion to balance the charge of the molecular. Thermogravimetry analysis indicates these complexes have the similar departure process and cyclic voltammogram exhibits a significant pair of redox peaks.     

Synthesis,crystal structures,and magnetic properties of three K[M(bpb)(CN)2]-based trinuclear sandwich-like heterobimetallic M(III)–Ni(II) (M = Fe,Cr, Co) complexes

Three trinuclear sandwich-type cyanide-bridged M^III–Ni^II complexes, {[Ni(cyclm)[Fe(bpb)(CN)₂]₂}·8H₂O (1), {[Ni(cyclm)[Cr(bpb)(CN)₂]₂}·2H₂O (2), and {[Ni(cyclm)[Co(bpb)(CN)₂]₂}·CH₃OH·2H₂O (3) (cyclm?=?1,4,8,11-tetraazacyclotetradecane), have been synthesized using K[M(bpb)(CN)₂] (M?=?Fe, Cr, Co; bpb?=?1,2-bis(pyridine-2-carboxamido)benzenate) as building block and one Ni(II) compound containing a 14-membered macrocycle ring as assembling segment. All the complexes have been characterized by elemental analysis, IR spectroscopy, and X-ray structure determination. Single X-ray diffraction analysis shows similar sandwich-like structures, in which the two cyanide-containing building blocks are monodentate through one of their two cyanides, coordinated face to face to the central Ni(II). Investigation of the magnetic properties of 1 and 2 reveals ferromagnetic magnetic coupling between the neighboring Fe(III)/Cr(III) and Ni(II) through the bridging cyanide. A best-fit to the magnetic susceptibilities of 1 and 2 based on the trinuclear M₂Ni model leads to magnetic coupling constants J?=?5.47(1)?cm^?1 for 1 and J?=?6.37(2)?cm^?1 for 2.     

Synthesis,thermal and spectroscopic properties,and crystal structures of [Co(bba)2(H2O)(phen)] and [Ni(bba)2(H2O)(butOH)(phen)] (bba = 2-benzoylbenzoate,phen = 1,10-phenanthroline,butOH = butanol)

Aquabis(2-benzoylbenzoato)(1,10-phenanthroline)cobalt(II) and aquabis(2-benzoylbenzoato)(butanol)(1,10-phenanthroline)nickel(II) have been prepared and characterized by elemental analyses, IR and electronic spectroscopy, magnetic measurements, and single-crystal X-ray diffraction. [Co(bba)₂(H₂O)(phen)] (1) and [Ni(bba)₂(H₂O)(butOH)(phen)] (2) consist of neutral monomeric units and crystallize in the monoclinic (P2(1)) and triclinic (P 1) crystal systems, respectively. The cobalt(II) and nickel(II) sit on inversion centres and exhibit distorted octahedral coordination. Phen is bidentate chelating. In 1, bba is both monodentate and bidentate, whereas in 2 bba is only monodentate. bba ligands are coordinated to metal(II) with carboxylates and IR spectra of both complexes display characteristic absorptions of carboxylate anions {ν(OCO)_asym and ν(OCO)_sym} of bba. Thermal analysis shows that mass losses of 1 from 105°C to 456°C correspond to decomposition of phen and bba, while for 2 these occur at 271–529°C.     

Synthesis and spectral studies of some new dimeric [(μ-Cl)2M2(L)2 · xTHF] [M = Zn(II) and Hg(II)] complexes containing Schiff-base ligands

A series of binuclear Schiff-base complexes of zinc(II) and mercury(II) containing bidentate ligands (HL) [HL?=?salicylidene-2-methyl-1-aminobenzene (HL¹), salicylidene-2-aminopyridine (HL²), and salicylidene-3-nitro-1-aminobenzene (HL³)] with “N” and “O” donors have been synthesized by simple metathetic reactions of anhydrous metal chlorides with sodium salts of Schiff bases (in tetrahydrofuran (THF)/MeOH) in equimolar ratio to produce [(µ-Cl)₂M₂(L)₂?·?xTHF] [where M?=?Zn(II) and Hg(II); L?=?HL¹, HL², and HL³; x?=?0 for (1), (4), (6) and x?=?2 for (2), (3), (5)]. The main emphasis on the complexes [(µ-Cl)₂M₂(L)₂?·?2THF] (2), (3), and (5) is given due to their five-coordinate environment around metal ions. The complexes have been characterized by elemental analyses (M, Cl, C, H, N), melting point, and spectral (FT-IR, ¹H-NMR, and ¹³C-NMR) studies. The structural composition of the complexes has been determined by FAB-MS spectral studies. FAB-MS showed the isotopic molecular ion peak [M⁺] and fragments supporting the formulation. Powder X-ray diffraction study of 6 is also reported showing the crystallite size (404.5?Å) of the complex.     

Halogen bonds and metal bonds involving superalkalies M2OCN/M2NCO (M = Li,Na) complexes

Structural Chemistry - A new type of halogen bond formed by supermetals or superalkalies with dihalogen molecules was analyzed by means of ab initio at the MP2/aug-cc-pVTZ level. The results reveal...     

Obtaining and catalytic properties investigation of the products of double-complex salts [Cr(ur)6][M(L)6] thermal oxidation (M = Co,Fe; L = CN−, 1/2C2O 4 2− )

Journal of Thermal Analysis and Calorimetry - In the current study, K-zeolites with different structure, Si/Al ratio and morphology have been prepared and then characterized by different techniques...     

Preparation,crystal structure,and thermal decomposition of an azide energetic compound [Cd(IMI)2(N3)2]n (IMI = imidazole)

Cadmium(II) imidazole (IMI) azide [Cd(IMI)₂(N₃)₂]_n (1) was synthesized using imidazole and azide, and was characterized by the elemental analysis and FTIR spectrum. The crystal structure was determined by X-ray single crystal diffraction, and the crystallographic data show that the crystal belongs to orthorhombic, Pba2 space group, α?=?10.780(4) Å, b?=?13.529(5) Å, and c?=?3.6415(12) Å. Its crystal density is 2.080?g·cm^–3. Cd(II) is a six-coordinate with six nitrogens from four imidazoles and two azides with μ–1,1 coordination. The thermal decomposition mechanism was determined based on differential scanning calorimetry (DSC) and thermogravimetry-derivative thermogravimetry (TG-DTG) analysis, and the kinetic parameters of the first exothermic process were studied using Kissinger’s method and Ozawa’s method, respectively. The energy of combustion, enthalpy of formation, critical temperature of thermal explosion, entropy of activation (ΔS ^≠), enthalpy of activation (ΔH ^≠), and free energy of activation (ΔG ^≠) were measured and calculated. In the end, impact sensitivity was also determined by standard method.     

Hydrothermal synthesis and structural characterization of a three-dimensional coordination polymer, [MnNa2(Hbtc)2(H2O)3] (btc = 1,2,4-benzenetricarboxylate)

A new three-dimensional metal-organic polymer, [MnNa₂(Hbtc)₂(H₂O)₃] (where btc?=?1,2,4-benzenetricarboxylate), has been prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction. The compound crystallized in the monoclinic space group C2/c, with cell parameters: a?=?8.2349(10), b?=?11.191(2), c?=?22.837(3)?Å, β?=?100.193(10)°, V?=?2071.3(6)?ų and Z?=?4. In the three-dimensional structure of the compound, each Na and Mn atom is six-coordinate with distorted octahedral geometry.     

Synthesis, crystal structure, EPR spectra of Cu2+ doped [Zn(methylisonicotinate)2(H2O)4]·(sac)2 single crystal

The tetraaquabis(methylisonicotinate)zinc(II) disaccharinate [hereafter, [Zn(mein)2(H2O)4]·(sac)2], complex has been synthesized and characterized by spectroscopic IR, EPR and X-ray diffraction technique. The octahedral Zn(II) ion, which rides on a crystallographic centre of symmetry, is coordinated by two monodentate mein ligands through the ring nitrogen and four aqua ligands to form discrete [Zn(mein)2(H2O)4] unit, which captures two saccharinate ions in up and down positions, each through intermolecular hydrogen bonds. The magnetic environments of Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 complex have been identified by electron paramagnetic resonance (EPR) technique. EPR spectra of Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 single crystals have been studied between 113 and 300 K in three mutually perpendicular planes. The calculated results of the Cu2+ doped [Zn(mein)2(H2O)4]·(sac)2 indicate that Cu2+ ion contains two different complexes and each complexes are located in different chemical environments and each environment contains two magnetically inequivalent Cu2+ sites in distinct orientations occupying substitutional positions in the lattice. The vibrational spectra of this compound were discussed in relation to other compounds containing methyl isonicotinate and saccharinate complexes. The assignments of the observed bands were discussed.     

Synthesis and characterisation of [tris(1,3-dithiole-2-thione-4,5-dithiolato)-stannate]2−, [Q]2[Sn(dmit)3], [tris(1,3-dithiole-2-one-4,5-dithiolato)stannate]2−, [Q]2[Sn(dmio)3] and [tris(1,3-dithiole-2-thione-4,5-selenolato)stannate]2−, [Q]2[Sn(dsit)3], complexes: Analysis of the structural variations of the [Sn(dmit)3]2− and [Sn(dmio)3]2− dianions

[Tris(1,3-dithiole-2-thione-4,5-dithiolato)stannate]²⁻, [Q]₂[Sn(C₃S₅)₃], [tris(1,3-dithiole-2-one-4,5-dithiolato)stannate]²⁻, [Q]₂[Sn(C₃S₄O)₃], and [tris(1,3-dithiole-2-thione-4,5-diselenolato)stannate]²⁻ [Q]₂[Sn(C₃S₃Se₂)₃], complexes, have been synthesised and characterised. Crystal structure determinations of [Q]₂[Sn(C₃S₅)₃] (Q=1,4-dimethylpyridinium, monoclinic and orthorhombic forms; NMe₄, NEt₄, and PPh₄) and [NEt₄]₂[Sn(C₃S₄O)₃] revealed variations in the overall dianion structures. The geometry about tin in each case is essentially octahedral with the chelate bite angles in the range 80.7(5)–87.45(4)°: the range of Sn–S distances is 2.5207(18)–2.571(17) Å. A statistical analysis, carried out on the crystal structure data for the six complexes, indicated that the most critical factors in controlling the overall shape of the dianion were the distances of the Sn atom from the dithiolate ligand planes [Sn–OOP]. Interanionic S⋯S interactions, within the sum of the van der Waals’ radii for two S atoms, are affected by the size of the cation, Q; the secondary connectivity is 3-dimensional for the smallest cations, Q=1,4-dimethylpyridinium and NMe₄, in chains for the somewhat larger cation, NEt₄ and is absent for the still larger, PPh₄ cation.     

The chemical identity of “[Ag(py)2]MnO4” organic solvent soluble oxidizing agent and new synthetic routes for the preparation of [Ag(py)n]XO4 (X = Mn,Cl, and Re,n = 2–4) complexes

Abstract

A widely used oxidizing agent in organic chemistry with an assumed structure of “[Ag(py)₂]MnO₄” and its perchlorate and perrhenate analogues are studied. Their synthesis in pure form is challenging. In order to clarify the chemical nature of the known compounds and find routes to new derivatives, a systematic study is presented for the synthesis of [Ag(py)_n]XO₄ (X?=?Mn, Cl, and Re, n?=?2–4) complexes. Ten complexes including four new derivatives, [Ag(py)₄]MnO₄, [Ag(py)₄]MnO₄·4[Ag(py)₂]MnO₄, [Ag(py)₂]ClO₄·0.5 py, and [Ag(py)₂]ReO₄, are synthesized and characterized. The chemical identity of “Ag(py)₂MnO₄” is also clarified. A novel route to prepare [Ag(py)₂]MnO₄ is developed. The reaction of AgXO₄ salts with neat pyridine followed by various crystallization techniques is used to prepare [Ag(py)₂]XO₄, [Ag(py)₄]XO₄, [Ag(py)₄]XO₄·4[Ag(py)₂]XO₄, and [Ag(py)₂]XO₄·0.5py (X?=?Cl, Mn) complexes. The solid phase structure of [Ag(py)₂]MnO₄·0.5py is determined (a?=?19.410 Å, b?=?7.788 Å, c?=?21.177 Å, β?=?104.20°, C2/c (15), Z?=?4 (3a)). [Ag(py)₂]⁺ cations in the crystal form dimeric units where silver ions are connected by oxygen atoms of two MnO₄^– anions. The Ag…Ag distance is indicative of argentophilic interactions. The pyridine ring π…π interactions contribute to the stability of the crystal lattice.     

Synthesis,crystal structures and magnetism of lanthanide(III) binuclear complexes [Ln2(μ1 ,3-CH3CO2)2(SCN−)4L2(H2O)6] (Ln = Gd(III) and Eu(III), L = 4-methylpyridine N-oxide)

Two lanthanide(III) binuclear complexes have been synthesized with acetate as bridging ligand and 4-methylpyridine N-oxide (L), SCN^? and H₂O as terminal ligands and structurally determined by X-ray crystallography. Both crystals [Gd₂(μ_1,3-CH₃CO₂)₂(SCN^?)₄(L)₂(H₂O₆) (1) and [Eu₂(μ_1,3-CH₃CO₂)₂(SCN^?)₄(L)₂(H₂O)₆] (2) belong to monoclinic with space group P2₁/n. The relevant cell parameters are as follows: a?=?9.0034(12)?Å, b?=?15.998(2)?Å, c?=?12.1277(17)?Å, β?=?100.625(2)° for complex 1; and a?=?9.0168(18)?Å, b?=?15.990(3)?Å, c?=?12.142(2)?Å, β?=?100.734(3)° for complex 2; The two lanthanide(III) ions are bridged by two acetate anions forming a binuclear unit, in which L, SCN^? and H₂O as unidentate terminal ligands take part in the coordination. The variable-temperature magnetic susceptibility of 1 was measured in the 4–300?K range; fitting for the susceptibility data reveals that there is no magnetic interaction between the bridged Gd(III) ions.     

[M(en)3]2Sn2Se6(M=Mn,Zn)的制备及其热稳定性

用有机溶剂热生长技术(SolvothermalTechnique)制备过渡金属锰和锌硒化物[Mn(en)3]2Sn2Se6(Ⅰ),[Zn(en)3]2Sn2Se6(Ⅱ).用单晶X射线衍射技术对其进行晶体结构分析.[Zn(en)3]2Sn2Se6样品的热分析结果表明,该化合物的热分解分三步进行.光学性质测试表明它们是半导体材料,[Mn(en)3]2Sn2Se6的能带隙为1.76eV.[Zn(en)3]2Sn2Se6的能带隙为2.49eV.