Syntheses and crystal structures of butterfly M2Te2 complexes of molybdenum and tungsten with functionalized cyclopentadienyl ligands

Reactions of singly-bonded dinuclear complexes [(η⁵-CH₃O₂CC₅H₄)₂M₂(CO)₆] (I, M?=?Mo; II, M?=?W) with the diarenylditelluride [4-CH₃C₆H₄Te]₂ in refluxing toluene for 4–6?h afforded dinuclear complexes 1 and 2 trans/ae-[(η⁵-RC₅H₄)₂M₂(CO)₄(μ-ArTe)₂] (Ar?=?4-CH₃C₆H₄Te). Complexes 1 and 2 were also synthesized by reactions of triply-bonded dinuclear complexes [(η⁵-CH₃O₂CC₅H₄)₂M₂(CO)₄] (III, M?=?Mo; IV, M?=?W) with [4-CH₃C₆H₄Te]₂ in refluxing toluene for 1?h. Both complexes have been characterized by elemental analysis, ¹H NMR, ¹³C NMR and IR spectroscopy and X-ray diffraction. Preliminary low-temperature NMR experiments on complexes 1 and 2 have revealed that in solution each complex goes through a rapid inversion of the butterfly four-membered ring M₂Te₂.     

Coordination of 2,3-diaminopyridine in the diamidopyridinium mode to the ReO3+ core

2,3-Diaminopyridine (H₂dap) reacts with (n-Bu₄N)[ReOCl₄] to form an air-stable salt of composition [ReO(Hdap)₂]Cl·2H₂O. Spectroscopic studies and X-ray crystallography show that Hdap is coordinated in the monoanionic diamidopyridinium mode to the oxorhenium(V) center. The protonation of the pyridyl nitrogens and the charge on the complex have no influence on the bond lengths and angles, with the rhenium(V)–oxo and average Re–NH bond lengths equal to 1.688(4) and 1.993(5) Å, respectively.     

Synthesis,crystal structure and luminescent properties of two complexes containing [Au(CN)2] − building blocks

Two supramolecular complexes, {{Ni(H₂O)(phen)₂[Au(CN)₂]}[Au(CN)₂]?·?1.5H₂O} _n (1) (phen?=?1,10-phenanthroline) and [H₂teta][Au₂(CN)₄]?·?2H₂O (2) (teta?=?5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyocloteradeca-4,11-diene) have been synthesized and structurally characterized. Complex 1 was a one-dimensional infinite chain constructed by [Au(CN)₂]^? building blocks. In complex 2, there are one cation, one anion, and two water molecules in the asymmetric unit. The two complexes are interconnected through a combination of aurophilic attractions and hydrogen bonds and formed into 3D supramolecular structures. The aqueous solutions of 1 and 2 display interesting luminescence at room temperature.     

Synthesis and structures of two cobalt complexes [NaCoII(NTA)(H2O)] n and NH4[CoIII(IDA)2] · 2H2O

Two cobalt complexes [NaCo^II(nta)(H₂O)] _n (H₃nta?=?nitrilotriacetic acid) (1) and NH₄[Co^III(ida)₂]?·?2H₂O (H₂ida?=?iminodiacetic acid) (2) have been synthesized and characterized by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the orthorhombic system, space group P2₁2₁2₁ with a?=?7.9770(12)?Å, b?=?9.7613(15)?Å, c?=?12.1945(18)?Å, V?=?949.5(2)?ų, Z?=?4, and R ₁?=?0.0705 for 1597 observed reflections. Compound 2 crystallizes in the monoclinic system, space group P2(1)/c with a?=?5.1801(3)?Å, b?=?11.2073(6)?Å, c?=?12.2891(7)?Å, V?=?707.09(7)?ų, Z?=?2, and R ₁?=?0.0349 for 1143 observed reflections. In compound 1, the Co is coordinated by a nitrogen and five oxygen atoms in a distorted octahedral geometry {CoNO₅}, and the Na is coordinated by one water molecule and four carboxyl oxygen atoms in slightly distorted square pyramidal geometry. The entire structure shows a three-dimensional network. In compound 2, Co atom is equatorially coordinated by two ida ligands in a distorted octahedral geometry {CoN₂O₄}. The discrete [Co(ida)₂]^2? anions are linked by hydrogen bonding to a three-dimensional supramolecular network.     

Synthesis and Crystal Structure of a Cadmium(II) Complex with 2,2′-diamino-4,4′-bis-1,3-thiazole

Crystals of the title complex with diaminobithiazole (DABT) were obtained by a solution diffusion method. X-ray diffraction analysis shows the complex to be monoclinic, space group P2₁/c with cell dimensions a=11.684(2), b=13.625(2), c=14.859(1) Å and β=109.970(7)°; R=0.026. The Cd(II) atom lies in a distorted octahedral environment with two DABT and two Cl ligands in a cis arrangement. The average internal dihedral angle of 9.3° between thiazole rings of DABT shows the twisted structure of the ligand in the complex. The Cd(II) atom deviates by some -0.570 Å from the mean plane of the thiazole ring containing N(4), but the Cd-N(4) bond is the shortest among four Cd-N bonds in the structure. Intramolecular H-bonds between Cl atoms and amino groups stabilize the cis-configuration of the complex.     

Synthesis and Crystal Structures of Two Zinc(II) Complexes with the Tripodal Ligand Tris(2-Benzimidazolymethyl)Amine

This article reports the synthesis and crystal structures of two new mononuclear Zinc(II) complexes, [Zn₂(NTB)₂(N₃)₂](NO₃)₂·2CH₃OH (1) and [Zn₂(NTB)₂(SCN)₂](NO₃)₂·2CH₃OH·H₂O (2). Complex 1 crystallizes in the triclinic system, space group P&1macr;, a=13.743(4), b=14.374(4), c=14.443(5) Å; α=77.053(5), β=81.824(5), γ=88.959(6)°; Z=2; R1=0.0418, wR2=0.0889. Complex 2 also crystallizes in the triclinic system, space group P&1macr;, a=12.203(10), b=14.430(12), c=18.541(15)Å; α=72.712(15), β=85.039(15), γ=73.610(14); Z=2; R1=0.0771, wR2=0.1288. In both cases the central zinc(II) metal ions are coordinated to the four nitrogen atoms of NTB and a nitrogen atom of N^- ₃(1) or SCN^-(2) to form distorted trigonal bipyramidal coordination spheres.     

Synthesis,Crystal Structure and Properties of a 4,4′-Bipyridine Bridged Trigonal-Bipyramidal Copper Homobinuclear Complex with Tris(2-Aminoethyl)amine

The synthesis of the binuclear complex [(tren)Cu(4,4'-bipy)Cu(tren)] (ClO₄)₄ where tren = tris(2-aminoethyl) amine and 4,4'-bipy = 4,4'-bipyridine, is described. Single-crystal X-ray diffraction study of the homobinuclear complex shows that two copper(II) ions are bridged by 4,4'-bipyridine and each copper(II) ion is trigonal-bipyramidally coordinated, with tren occupying four sites [Cu-N = 2.030(2), 2.047(2), 2.078(2), and 2.119(2) Å respectively] and a bridging 4,4'-bipyridine in the apical position. The Cu-Cu distance is 11.11 Å. In variable-temperature ESR spectra, the presence of hyperfine structure suggest that some interaction exists between the two copper(II) ions. Temperature-dependent susceptibility studies indicate that it is a weak ferromagnetic interaction with 2J = 1.23 cm^-1.     

pH-controlled assembly of two new supramolecular hybrid compounds based on Keggin polyoxotungstates

Two supramolecular compounds based on Keggin polyoxotungstates, (4,4′-H₂bpy){[Cu(4,4′-bpy)]₂[SiW₁₂O₄₀]} (1) and (4,4′-H₂bpy)₂[SiW₁₂O₄₀]·2H₂O (2) have been synthesized and characterized by elemental analyses, IR, UV, XPS spectra, TG analyses, and single crystal X-ray diffraction analyses. Compound 1 exhibits an infinite 1-D ladder like structure, which is further interconnected into a 3-D supramolecular framework via hydrogen bonding interactions. Compound 2 contains 4,4′-bipyridine (4,4′-bpy), pseudo-Keggin polyoxoanions [SiW₁₂O₄₀]^4?, and water molecules. Polyoxoanions together with water molecules in 2 construct a 3-D inorganic supramolecular network through O···O and O···Ow(1) interactions. The electrochemical behaviors and photocatalytic properties of 1 and 2 have been investigated.     

A one-dimensional zigzag chain involving a cadmium(II)-imino nitroxide: structure and magnetic properties

A novel one-dimensional complex salt with the formula [Cd(IM2py)₂][Au(CN)₂]₂ (IM2py?=?2-(2′-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl), has been synthesized and its structure was determined by single-crystal X-ray diffraction methods. The coordination geometry around Cd(II) ion is a distorted octahedral. IM2py coordinates to Cd(II) via pyridyl- and imino-N atoms to form a planar, five-membered chelate ring. [Cd(IM2py)₂][Au(CN)₂]₂ units are linked through weak Au?···?Au interactions, generating an infinite 1D zigzag chain. Magnetic studies show weak antiferromagnetic coupling between two radicals through the diamagnetic Cd(II) ion.