Bis(4′-phenyl-2,2′:6′,2″-terpyridine)ruthenium(II): Holding the {Ru(tpy)2} embraces at bay

The solid state structure of [Ru(Phtpy)₂][PF₆]₂ · 4MeCN has been determined (Phtpy = 4′-phenyl-2,2′:6′,2″-terpyridine); [Ru(Phtpy)₂]²⁺ cations pack into sheets by virtue of {M(tpy)₂}₂ embraces, and the MeCN solvent molecules are involved in NH–C interactions which prevent the efficient packing of adjacent sheets. Comparisons with related structures lead to some generalizations about packing motifs in salts containing [M(Phtpy)₂]²⁺ or [M(pytpy)₂]²⁺ cations (pytpy = 4′-pyridyl-2,2′:6′,2″-terpyridine).     

Synthesis and X-ray crystal structure determination of monomeric cis-Pd(2,2′-bipyridine)(NO3)2

Complex cis-Pd(2,2′-bipyridine)(NO₃)₂ was synthesized by the reaction of cis-Pd(2,2′-bipyridine)Cl₂ with AgNO₃ in water and crystallized by vapor diffusion of diethyl ether into an acetonitrile solution of the complex. The crystal structure obtained shows that each of the two nitrate ligands are coordinated through oxygen atoms to the Pd(2,2′-bipyridine)²⁺ center in unidentate fashion. IR and ¹H NMR spectral data were also obtained.     

Diplatinum(III) [Cl2(μ2-amidinate)4] compound derived from air oxidation of mononuclear cis-[Pt(NH3)2(amidine-κ)2] complex

The dinuclear platinum(III) complex [Pt₂Cl₂{μ₂-N(H)C(Et)N(H)}₄] (2) has been prepared by heating cis-[Pt(NH₃)₂{NHC(NH₂)Et}₂](Cl)₂ (cis-1) under aeration conditions in an EtOH/H₂O mixture at 70 °C for 2 d and it was characterized by elemental analyses (C, H, N), ESI⁺-MS, IR, ¹H and ¹³C NMR spectroscopies and also by X-ray diffraction. Complex 2 represents the second Pt^III dimer stabilized by the amidinate ligand ever known and it has a lantern-type structure with four amidinate ligands bridging two Pt^III centers with Pt–Pt distance of 2.4809(2) Å.     

Direct growth of Cu3(BTC)2(H2O)3 · xH2O thin films on modified QCM-gold electrodes – Water sorption isotherms

The preparation of a thin film of the metal–organic framework Cu₃(BTC)₂(H₂O)₃ · xH₂O (HKUST-1) on the gold electrode of a quartz-crystal microbalance (QCM) was achieved by direct growth on a 11-mercaptoundecanol self-assembled monolayer (SAM). The formation of the SAM on the gold substrate was proven via reflection–absorption infrared-spectroscopy. The HKUST-1 thin film was characterized by X-ray diffraction, Raman-spectroscopy, and scanning-electron microscopy. Water vapor sorption measurements allow us to directly characterize the sorption properties of the thin film grown on the electrode of the QCM-device.     

A hemidirected 1-D coordination polymer [Pb2(H2O)2(HBTC)2] · 3H2O extended in holodirected 3-D by weak Pb–O interactions

A new complex, [Pb₂(H₂O)₂(HBTC)₂] · 3H₂O (H₃BTC = 1,3,5-Benzenetricarboxylic acid) (1), has been synthesized under hydrothermal condition. The single-crystal analysis shows that 1 consists of 1-D double-chains with Pb(II) six-coordinated by three H₃BTC and one H₂O molecule with the Pb–O bond distances in the range of 2.56–2.76 Å. When the Pb–O bonding limit extends from 2.76 to 2.90 Å, the potential weak bonds of Pb–O can be found and the coordination number of Pb will increase from six to nine. As a result, the coordination geometry of Pb(II) transforms from hemidirected to holodirected and an infinite 3-D framework is obtained by the connection of the double-chains. The IR spectrum and the TGA–DTA curve of 1 are also reported in this paper.     

Ferromagnetic coupling in a novel dicyanamide-bridged dinuclear gadolinium(III) complex [Gd2(dca)4(OH)2 (NITpPy)4] (NITpPy = 4-pyridyl-nitronyl nitroxide radical)

The novel six-coordinated gadolinium(III) complex of formula [Gd₂(dca)₄(OH)₂(NITpPy)₄] (1) (dca = dicyanamide, NITpPy = 4-pyridyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-oxy-3-oxide) has been prepared and characterized by X-ray crystallography. Compound 1 is a dimer structure made up of double μ_1,5-dca-bridged gadolinium(III) ions and one terminal dca ligand; variable-temperature magnetic susceptibility measurements reveal the occurrence of a significant ferromagnetic interaction directly spin polarization through the NITpPy–Gd(III)–NITpPy pathway with J = 11.56 cm⁻¹.     

Synthesis, structure and photoluminescence of a novel palladium(I) compound: [Pd3(μ3-Cl)2(dppp)3][Pd2(μ2-Cl)3(PPh3)2](PPh3)2

Pd(PPh₃)₂Cl₂ reacts with PdCl₂ and 1,3-bis(diphenylphosphine)propane (dppp) in ethanol–DMF–pyridine mixed solvent to yield a novel palladium(I) compound [Pd₃(μ₃-Cl)₂(dppp)₃][Pd₂(μ₂-Cl)₃(PPh₃)₂](PPh₃)₂. It features an isolated structure based on [Pd₃(μ₃-Cl)₂(dppp)₃]⁺ cations having triangulo-palladium clusters and [Pd₂(μ₂-Cl)₃(PPh₃)₂]⁻ anions in which the coordination environment of palladium is an unusual tetrahedral geometry. Its photoluminescence is measured.     

A new binuclear potassium (І) complex with a novel 1D infinite water chain containing (H2O)12 clusters

A novel 1D infinite water chain made of (H₂O)₁₂ clusters containing two different chair water hexamers is found in the binuclear coordination compound, [K₂(L)₂(phen)₄]·6H₂O (1) (where L = 2,2′-azanediyldibenzoic dianion, phen = 1,10′-phenanthroline), which has been synthesized and structurally characterized by single-crystal X-ray diffraction. The fluorescence spectrum and thermogravimetric analysis (TGA) of the title complex 1 have been also discussed.     

Molecular structures and vibrational frequencies for cis-[PdCl2(tmen)] and cis-[Pd(N3)2(tmen)]: A DFT study

Theoretical molecular structures of the complexes cis-[PdCl₂(tmen)] and cis-[Pd(N₃)₂(tmen)] (tmen = N,N,N′,N′-tetramethylethylenediamine) were investigated using B3LYP/DFT method. The calculated molecular parameters, bond distances and angles, revealed a square-planar geometry around the metallic center for both compounds with the azide being linear. The theoretical infrared spectra of C₁ symmetry (electronic state ¹A) of the compounds are in agreement with the experimental data.     

Synthesis of a fluorescent gold(I) complex with a thiosemicarbazone, [Au2(3-NO2-Hbtsc)4]Cl2 · 2CH3CN

Direct reaction of gold(I) chloride with 3-nitrobenzaldehyde thiosemicarbazone (3-NO₂-Hbtsc) in the presence of triphenylphosphine in acetonitrile has yielded ionic complex, [Au₂(3-NO₂-Hbtsc)₄]Cl₂ · 2CH₃CN (1). It exhibited an intense fluorescence band (λ_em) at 383 nm (λ_ex = 300 nm), and two bands of medium intensity at 413 and 436 nm (λ_ex = 350 nm). Complex 1 represents first example of ionic gold(I) complex with a thiosemicarbazone.     

Synthesis and structures of dinuclear copper(II) complex and μ-phenolatotetrazinc(II) complex with 1,3-diphenyl-4-(salicylidene hydrazone)-phenylethylene-pyrazolone-5

Novel dinuclear copper(II) complex and phenoxy-bridged tetranuclear zinc(II) complex with 1,3-diphenyl-4-(salicylidene hydrazone)-phenylethylene-pyrazolone-5 (DPPeP-SAH) have been synthesized and characterized by X-ray crystallography. The X-ray diffraction analyses of the complexes show that two Cu(II) centers are bonded with two tetradentated ligands and the geometries around the central ions are slightly distorted square planar, while in zinc(II) complex central metal ions are held together by four μ-phenoxo bridges that lead to the formation of the tetra-μ-phenolatotetrazinc(II) centers.     

Direct synthesis and characterization of novel homo- and heterometallic mixed-ligand tetrazolate complexes, Cu(en)(tz)2 and Cu(en)2Zn(tz)4 [en = ethylenediamine, tz = tetrazolate]

For the first time, tetrazolate complexes have been prepared by direct synthesis. Two novel homo- and heterometallic mixed-ligand complexes, Cu(en)(tz)₂ and Cu(en)₂Zn(tz)₄, have been synthesized using tetrazole (Htz), ethylenediamine (en), metallic copper and zinc oxide as starting materials. Both tetrazolates were characterized by single-crystal X-ray diffraction, IR spectroscopy and thermal analysis. The complexes present 1D coordination polymers, with tetrazolate anions acting as both monodentate and bridging ligands.     

Directing Group‐Assisted Copper(II)‐Catalyzed ortho‐Carbonylation to Benzamide using 2,2′‐Azobisisobutyronitrile (AIBN)

An efficient copper‐catalyzed regioselective C—H bond carbonylation of benzamides has been developed using 2,2′‐azobisisobutyronitrile (AIBN) as traceless cyanating agent. The non‐toxic and readily available AIBN was used for the carbonylative cyclization of benzamides via copper catalysis. The method is also applicable for the regioselective cyanation of furan, benzofuran, thiophene, benzothiophene, and pyrrole carboxamide derivatives.

     

Supramolecular π–π assembly of a neutral [Cu(salen)] complex via the templating effect of an ionic inorganic complex Na2[Cu(mnt)2] forming a framework type material having well-defined channels

A classical ionic inorganic complex Na₂[Cu(mnt)₂] (mnt²⁻ = maleonitriledithiolate = 1,2-dicyanoethylenedithiolate), that acts as a template in assembling neutral [Cu(salen)] (salen = bis(salicylidene)ethylenediamine) complexes forming a framework type arrangement, is accommodated in the channel formed in the crystal structure of a new type of host–guest compound [Cu(salen)]₄ · Na₂[Cu(mnt)₂] (1). The non-covalent supramolecular interactions among [Cu(salen)] complexes and between [Cu(salen)] and [Cu(mnt)₂]²⁻ complexes in the crystal lattice of 1 result in weak antiferromagnetic coupling.     

Underlying mechanism of the hydrothermal instability of Cu3(BTC)2 metal-organic framework

Water induced decomposition of Cu₃(BTC)₂ (BTC= benzene-1,3,5-tricarboxylate) metal-organic framework (MOF) was studied using dynamic water vapour adsorption. Small-angle X-ray scattering, Fourier transform infrared spectroscopy and differential scanning calorimetry analyses revealed that the underlying mechanism of Cu₃(BTC)₂ MOF decomposition under humid streams is the interpenetration of water molecules into Cu-BTC coordination to displace organic linkers (BTC) from Cu centres.     

Two novel isomeric complexes supported by vanadates {V4O12}: [{Cu(dpa)2}2V4O12] (dpa = 2,2′-dipyridylamine)

Two Cu(II) complexes supported by tetravanadates, [{Cu(dpa)₂}₂V₄O₁₂] (1 and 2), have been synthesized under hydrothermal reactions. Structural analysis indicates that complexes 1 and 2 are isomeric and consist of a cyclic [V₄O₁₂]^4- anion bridged to two [Cu(dpa)₂]²⁺ moieties. Close inspection of complexes 1 and 2 reveals that the [V₄O₁₂]^4- anions adopt chair-like and boat-like configurations respectively, and are coordinated to each Cu(II) ions through a single terminal oxygen atom of two cross vanadium sites. Moreover, Complexes 1 and 2 exhibit trans- and cis-configurations, respectively.     

A novel infinite 1D covalent chain of end-to-end thiocyanato bridged heptacoordinated cadmium(II)Schiff base: π…π interaction and weak C–H…S hydrogen bonded supramolecule

A new Schiff base, N,N′-(bis(pyridin-2-yl)formylidene)ethane-1,2-diamine (bpfd) is prepared and used to synthesize a novel end-to-end thiocyanato bridged infinite 1D polymeric heptacoordinated cadmium(II) chain [Cd(bpfd)(μ_1,3-NCS)(NCS)]_n (1) which forms a 3D supramolecule through weak C–H…S hydrogen bonding and π…π interaction.     

Metal-organic framework Cu3 (BTC)2(H2O)3 catalyzed Aldol synthesis of pyrimidine-chalcone hybrids

A typical metal organic framework, [Cu₃ (BTC)₂(H₂O)₃, BTC = 1,3,5-benzene tricarboxylate] has been used for the synthesis of pyrimidine-chalcones. We have explored a green synthesis of pyrimidine chalcones under Cu₃(BTC)₂ catalysis by Aldol condensation. Easy isolation of product, excellent yield, and recyclable catalyst makes this reaction eco-friendly. The technology was demonstrated to be applicable to the synthesis of a host of chemical hybrids.     

Crystallography and Structure–Property Relationships in 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐Dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐ Quaterphenyl (DODECA)

X‐ray crystallographic study of 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐quaterphenyl (DODECA) has been carried out. Nonbonding interatomic distances of oxygen atoms inside of all the nitro groups are shorter than those corresponding to the intermolecular contact radii for oxygen. By means of the DFT B3LYP/6‐31(d, p) method a difference of 136 kJ mol⁻¹ between the X‐ray and DFT structures of DODECA was found. The bearer of the highest initiation reactivity in its molecule in solid phase should be the nitro group at 4′′′‐position, in contrast to those at 2′‐ or 2″‐positions in its isolated molecule. The most reactive nitro group in the DODECA molecule can be well specified by the relationship between net charges on nitro groups and charges on their nitrogen atoms, both of them for the X‐ray structure. The ¹⁵N chemical shift, corresponding to this nitro group for the initiation by impact and shock, correlates very well with these shifts of the reaction centers of the other six “genuine” polynitro arenes.     

A novel Keggin-type tungstogermanate dimer bearing dinuclear copper-organic coordination ions: {H8[Cu(phen)(μ2-CH3COO)2Cu(phen)(H2O)]2[Ge2W23CuO80]} · 24H2O

An unprecedented Keggin-type tungstogermanate dimer bearing dinuclear copper-organic coordination ions {H₈[Cu(phen)(μ₂-CH₃COO)₂Cu(phen)(H₂O)]₂[Ge₂W₂₃CuO₈₀]} · 24H₂O has been synthesized and characterized by IR, UV, ICP analyses, ESR spectra, element analysis, TG and single crystal X-ray diffraction analysis. The compound is built up from a dimeric heteropolyanion constituted by two corner-shared Keggin-type building subunits and two dinuclear copper-organic coordination cations [Cu(phen)(μ₂-CH₃COO)₂Cu(phen)(H₂O)]²⁺, each of which consists two square pyramidal copper-phen ions bridged by two μ₂-acetate ligands.