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Angioedema with life-threatening site is one of the most impressive and serious reasons for presenting to the ENT doctor. Among different causes (tumors, local infections, allergy reactions), an important cause is the side-effect of the angiotensin converting enzyme (ACE) inhibitors drugs. ACE-inhibitors-induced angioedema is described to be the most frequent form of bradykinin-mediated angioedema presented in emergency and also one of the most encountered drug-induced angioedema. The edema can involve one or more areas of the head and neck region, the most affected being the face, the lips, the tongue, followed by the larynx, when it may determine respiratory distress and even death. There are no specific diagnosis tests available and the positive diagnosis of ACE-inhibitors-induced angioedema is an exclusion diagnosis. The authors performed a review of the most important characteristics of the angioedema caused by ACE-inhibitors and present their experience emphasizing the diagnostic algorithm.

1-D coordination polymers, 1∞[Zn(fl)2]·2EtOH and 1∞[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip = N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400 °C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1∞[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1∞[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated.

International audience; Five new cyanido-bridged heterometallic coordination polymers have been obtained by reacting PPh4[RuIII(salpn)(CN)2]·H2O (1) and AsPh4[RuIII(valen)(CN)2]·8.5H2O (2) (H2salpn and H2valen being Schiffbase proligands resulting from the condensation reaction of salicylaldehyde with 1,3-propanediamine and, respectively, o-vanillin with 1,2-ethanediamine) with divalent transition metal perchlorate salts: 1 1 [{RuIII(salpn)(CN)2}3{MII(DMF)3}2](ClO4)·4DMF (MII = Mn, 3; Co, 4) and 12 [{RuIII(valen)(CN)2}4{MII(DMF)3}2 {MII(DMF)4}](ClO4)2·4DMF (MII = Mn, 5; Co, 6; Ni, 7), respectively. The dicyanido species, trans-[Ru(salpn) (CN)2]− and trans-[Ru(valen)(CN)2]−, act as metalloligands with the 3d metal ions. Compounds 3 and 4 are isostructural one-dimensional (1D) coordination polymers with a ladder topology. Each MII ion is hexacoordinatedby three cyanido groups arising from three {Ru(salpn)(CN)2} units and by the oxygen atoms from three DMF molecules, which are coordinated at meridional positions. Compounds 5–7 are also isostructural, their structures consisting of 2D networks with a herringbone topology. The magnetic susceptibility measurements of these 1D and 2D systems reveal the presence of dominating RuIII–MII antiferromagnetic (AF) interactions in compounds 3, 4, 5 and 6, while ferromagnetic RuIII–NiII interactions are observed in 7. All these compounds stay in their paramagnetic state down to 1.8 K except compound 4 which possesses a 3D ordered AF ground state.

A series of novel derivatives of 3,5-dinitro-4-methoxyamino-benzoic acid were synthesized and fully characterized. Synthesis were performed by simple coupling reactions of the starting material with benzylamine, n-butylamine, 4-amino-antipyrine, benzocaine, 3,4-dimethyl-5-amino-isoxazole, 3,4-dimethoxyphenyl-2-ethylamine; besides, the corresponding methyl ester was also synthesized. The structural characterization of the new compounds was made by elemental analysis, IR, 1H and 13C NMR, UV–Vis, ESR, cyclic voltammetry, and single crystal X-ray diffraction (where appropriate). All compounds exhibits reversible acid-base behavior accompanied by colour change (yellow in acid media and blue at basic pH). Cyclic voltammetry showed an irreversible oxidation peak, however by chemical oxidation, these compounds generates persistent free radicals, evidenced also by ESR. Hydrophobicity and total antioxidant capacity of the compounds were also evaluated.

Three new 1D cyanido-bridged 3d-4f coordination polymers, {[Gd(L)(H2O)2Fe(CN)6]·H2O}n(1GdFe), {[Dy(L)(H2O)2Fe(CN)6]·3H2O}n(2DyFe), and {[Dy(L)(H2O)2Co(CN)6]·H2O}n(3DyCo), were assembled following the building-block approach (L = pentadentatebis-semicarbazone ligand resulting from the condensation reaction between 2,6-diacetyl-pyridine and semicarbazide). The crystal structures consist of crenel-like LnIII-MIIIalternate chains, with the LnIIIions connected by the hexacyanido metalloligands through twociscyanido groups. The magnetic properties of the three complexes have been investigated. Field-induced slow relaxation of the magnetization was observed for compounds2DyFeand3DyCo. Compound3DyCois a new example of chain of Single Ion Magnets.&nbsp

Three Schiff base ligands derived from 2-aminofluorene and 3-methoxysalicylaldehyde (HL1), 3-ethoxysalicylaldehyde (HL2), or 2-formyl-6-hydroxymethyl-p-cresol (HL3) were synthesized and structurally characterized by X-ray diffraction on single crystals. The mononuclear complexes [Zn(L1)2] (4), [Zn(L2)2] (5), [Zn(L3)2]·CHCl3 (6a), and [Zn(L3)2] (6b) containing the monoanionic form of these ligands were obtained and structurally characterized. Luminescent properties of the ligands and complexes were investigated in solid-state.

We describe herein synthesis of novel hydroxy-bis-2,5-disubstituted-1,3,4-oxadiazoles and their ability to emit green light, through ESIPT mechanism. Unlike previous reports, our compounds exhibit very good quantum yields, most likely avoiding the presumed intramolecular fluorescence quenching in presence of the second oxadiazole moiety. Studies regarding behaviour of the compounds in polar and non-polar solvents are also described, indicating the possibility to modulate the emission according to the environment. The solid-state structural analysis, corroborated with fluorescence data, suggest the importance of the tert-butyl group in preservation of the luminescent properties. The corresponding benzyl-protected compounds, precursors to the target hydroxy-bis-2,5-disubstituted-1,3,4-oxadiazoles were also investigated for their optical properties and found to display very intense blue emission, with quantum yields values in dichloromethane (between 0.423 and 0.499) almost equal to the standard quinine sulfate.

A binuclear complex, [Ni2L2(NO3)(H2O)(CH3CN)]ClO4·CH3CN (1), has been obtained using a Schiff-base ligand (HL) derived from o-vanillin and 4-(2-aminoethyl)morpholine. The crystal structure of 1 has been solved. Both Ni(II) ions are hexacoordinated, but they display different coordination spheres. The exchange interaction between the two nickel ions is antiferromagnetic (J = −7.9 ± 0.2 cm−1; H = −JS1S2), in line with the DFT calculations. Compound 1 has been tested as a catalyst in the epoxidation of various olefins. The reaction of the same ligand with a mixture of cobalt(II) perchlorate and nitrate affords a mononuclear Co(III) complex, [CoL2(H2O)]ClO4·CH3OH (2).

Two new alkoxido-bridged heterometallic complexes of formula [CoIICoIII 3CuII 3(dea)6(CH3COO)3](ClO4)0.75(CH3COO)1.25 (1) and [CoII 2CoIII 2ZnII 3(tea)2(piv)6(CH3O)2(OH)2(CH3OH)2]·H2O 2 (H2dea=diethanolamine, H3tea=triethanolamine and Hpiv=pivalic acid) have been assembled using aminoalcohol ligands. The cationic core in 1 possesses a threefold crystallographic axis, and it exhibits a set of three copper(II), one cobalt(II) and three cobalt(III) ions arranged as a hexagon of alternating copper(II) and cobalt(III) ions around the central cobalt(II) ion. Each edge of the hexagon is defined by a double alkoxido bridge, the outer one being bis-monodentate with copper(II)-cobalt(III) pair whereas the inner one adopts a tris-monodentate coordination mode linking the Cu(II)-Co(III) pair with the central cobalt(II) ion. The acetate groups act as bidentate ligands towards the copper(II) ions. The intramolecular cobalt(II)-copper(II) separation is 3.157Å. A hexagon of two cobalt(II), two cobalt(II) and two zinc(II) ions distributed along three types of edges with a central zinc(II) ion occurs in 2. A tris-modentate alkoxido bridge is involved in all edges together with another bis-monodentate alkoxido bridge (CoIII-CoII and CoII-ZnII pairs) and a carboxylate-pivalate bridge in the syn-syn conformation. The five coordination at each peripheral zinc(II) ion is completed by a monodentate carboxylate-pivalate ligand whereas a methoxo group allows to achieve the six-coordination at each cobalt(III) ion. The intramolecular cobalt(II)-cobalt(II) separation through the inner zinc(II) ion is 6.309Å. The magnetic properties of 1 and 2 have been investigated in the temperature range 1.9-300K. The exchange interaction between the six-coordinate cobalt(II) and copper(II) ions through the double alkoxido bridges in 1 and that between the six-coordinate cobalt(II) ions across the diamagnetic zinc(II) ion in 2 are found to be ferromagnetic [J =+5.39(5) (1) and +1.05(2)cm-1 (2)], the accidental orthogonality between the interacting magnetic orbitals accounting for this behaviour in the two cases.

By reacting [MII(valpn)] or [MII(valdmpn)] mononuclear complexes with 4-aminopyridine in different molar ratios, five [MII(valXpn)(4-NH2-py)] and one [NiII(valdmpn)(4-NH2-py)2] complexes were obtained and structurally characterized (MII = NiII, CuII, ZnII; valpnH2 and valdmpnH2 are the Schiff bases resulted from the condensation of o-vanillin with 1,3-propylenediamine and 2,2-dimethyl-1,3-propylenediamine respectively). In the [Cu(valpn)(4-NH2-py)], [Ni(valpn)(4-NH2-py)], [Zn(valpn)(4-NH2-py)] and [Ni(valdmpn)(4-NH2-py)] complexes the metal ions are pentacoordinated with a square pyramidal geometry. The specific hydrogen bond interactions of the amino group belonging to the 4-aminopyridine with the free O2O′2 compartment of the Schiff base ligands led to various supramolecular architectures: rectangles, chains, and ladders. The spectroscopic properties of the compounds were also investigated.

The supramolecular interactions between 1,3-bis(4-pyridyl)azulene (azbbpy) as a hydrogen bond acceptor and a variety of aromatic hydrogen-bond donors produced new binary molecular co-crystals and a salt. All crystal structures display extensive and very complex hydrogen bond networks containing both homo- and heterosynthons formed through robust O–H⋯N and OH⋯O hydrogen bonds. The binary co-crystals of azbbpy with 4,4′-biphenol and 4,4′-oxo-bis-benzoic acid in a 1 : 1 ratio revealed that the recognition process differs. While 4,4′-biphenol acts both as a donor and an acceptor of protons, generating a two-dimensional supramolecular network in which azbbpy interacts with only one pyridine moiety, the co-crystallization with 4,4′-oxo-bis-benzoic acid yielded zig-zag chains formed by alternating acid–pyridine supramolecular heterosynthons. Co-crystallization with isophthalic acid yields a 2 : 1 system, 4, as hydrogen-bonded zig-zag supramolecular chains containing a R44(36) graph set organized through strong OH⋯N and weak C–H⋯N hydrogen bonds. Co-crystallization of azbbpy with trimesic acid in different ratios yielded two distinct systems: co-crystal 5 and salt 6. In 5, the trimesic acid molecules are assembled in supramolecular helical chains which are further connected by azbbpy through hydrogen bonding and π–π interactions into a 3D architecture with channels that host water molecules. A complicated supramolecular 3D architecture is also established between trimesic anions and azbbpyH+ cations in crystal 6, resulting in channels filled with disordered solvent molecules. These types of interactions were also evidenced in a quantitative way and confirmed on grounds of the Hirshfeld surface mapped with geometrical parameters that characterize close contacts in co-crystals. The optical properties of these supramolecular systems showed strong absorption bands in the visible region due to the azulene fragment.

N-Acylhydrazones have been described as responsive compounds to a wide variety of triggers that are able to induce reversible structural changes. These reversible constitutional, conformational or configurational changes caused by physical or chemical stimuli are useful tools in designing molecular switches. We report herein bis-N-acylhydrazones as new switchable-light emissive molecules triggered by light and/or solvents. The emissive properties could be explained by phototautomerisation (Excited State Intramolecular Proton Transfer) and by formation of aggregates (Aggregation-Induced Emission). We investigated the influence of structural particularities brought in by electron-donor or electron-withdrawing substituents as well as the requirement of several hydrazone bonds in the molecular structure for the generation of light.

Literature data are abundant in oxidations catalyzed by nitroxides free radicals, while hydrazyls free radicals are very seldom encountered. In this work we made a comparison between some nitroxides and hydrazyl free radicals towards the ability to selectively oxidize activated alcohols to the corresponding carbonyl derivatives. As nitroxides we used 2,2,6,6-tetramethylpirrolidin-N-oxide (TEMPO) and phtalimide-N-oxyl (PINO) free radicals, while as hydrazyls were used 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-p-nitrophenyl-1-picrylhydrazyl (DN-DPPH). The differences in the physico-chemical properties between nitroxides and hydrazyls were evaluated by UV–vis, EPR and cyclic voltammetry. For DN-DPPH the X-ray crystal structure was resolved. It has been shown that a nitroxide radical is a far better catalyst in such aerobic oxidations comparatively with a hydrazyl one. The explanation of these results consists firstly in a different mechanism involved in the oxidation procedures and secondly in the variation of the oxidation potentials of nitroxides comparatively with hydrazyls.

The reaction of silver perchlorate with 2-phenyl-5-( p -tolyl)-1,3,4-oxadiazole ( L ) affords a 1-D coordination polymer, [Ag 3 L 4 (ClO 4 ) 3 ] ( 1 ). Two silver ions are bridged by two L ligands, through the nitrogen atoms of the oxadiazole ring, resulting in binuclear units. The coordination polymer is constructed from binuclear nodes, {Ag 2 L 2 }, connected by perchlorato bridges. The investigation of the optical properties of compound 1 indicates a slight change in the emission profile compared to the organic ligand, showing blue luminescence upon excitation at λ = 300 nm.

Five new cyanido-bridged heterometallic coordination polymers have been obtained by reacting PPh4[RuIII(salpn)(CN)2]·H2O (1) and AsPh4[RuIII(valen)(CN)2]·8.5H2O (2) (H2salpn and H2valen being Schiff-base proligands resulting from the condensation reaction of salicylaldehyde with 1,3-propanediamine and, respectively, o-vanillin with 1,2-ethanediamine) with divalent transition metal perchlorate salts: ∞1[{RuIII(salpn)(CN)2}3{MII(DMF)3}2](ClO4)·4DMF (MII = Mn, 3; Co, 4) and ∞2[{RuIII(valen)(CN)2}4{MII(DMF)3}2{MII(DMF)4}](ClO4)2·4DMF (MII = Mn, 5; Co, 6; Ni, 7), respectively. The dicyanido species, trans-[Ru(salpn)(CN)2]- and trans-[Ru(valen)(CN)2]-, act as metalloligands with the 3d metal ions. Compounds 3 and 4 are isostructural one-dimensional (1D) coordination polymers with a ladder topology. Each MII ion is hexacoordinated by three cyanido groups arising from three {Ru(salpn)(CN)2} units and by the oxygen atoms from three DMF molecules, which are coordinated at meridional positions. Compounds 5-7 are also isostructural, their structures consisting of 2D networks with a herringbone topology. The magnetic susceptibility measurements of these 1D and 2D systems reveal the presence of dominating RuIII-MII antiferromagnetic (AF) interactions in compounds 3, 4, 5 and 6, while ferromagnetic RuIII-NiII interactions are observed in 7. All these compounds stay in their paramagnetic state down to 1.8 K except compound 4 which possesses a 3D ordered AF ground state.

Three new 1-D coordination polymers, [Co(valpn)Gd(hfac)2(IN)]n (1), [Ni(valpn)Gd(hfac)2(IN)]n (2), and [Ni(valpn)Dy(hfac)2(IN)]n (3), were constructed by connecting {MII(valpn)LnIII(hfac)2} nodes through isonicotinato spacers (IN−), with hexafluoroacetylacetonato being hfac and 1,3-propanediylbis(2-iminomethylene-6-methoxy-phenol) (H2valpn) being the Schiff base obtained from the condensation reaction between o-vanillin and 1,3-diaminopropane. The synthetic approach relied on the substitution of the acetate ligands from the binuclear precursors [MII(CH3OH)(valpn)LnIII(hfac)2(CH3COO)] with the isonicotinato ligand. The investigation of the magnetic properties of all compounds showed a ferromagnetic interaction attributed to the intranode exchange interaction between the 3d and 4f metal ions. For compound 3, the AC magnetic measurements indicated a field-induced slow relaxation of the magnetization of the [NiIIDyIII] nodes.

A number of ten stable free mono-, di- and tri-radicals of the TEMPO nitroxide type were synthesized and characterized via physico-chemical methods (elemental analysis, MS, UV-Vis, IR, ESR, and X-ray, where appropriate). The design of the compounds was chosen such that supramolecular interaction could be gained via hydrogen-bonding or π–π interactions; therefore the compounds should contain amino- or urea-moieties, (nitro)aromatic rings, or a crown ether residue. The formation of inclusion complexes between these (poly)radicals and cucurbit[6]uril was studied via Electron Spin Resonance (ESR) spectroscopy. The binding constants were evaluated from the analysis of the rotational correlation time dependence on the concentration of cucurbit[6]uril. These constants are an order of magnitude lower than the values reported before for complexes of TEMPO derivatives with β-cyclodextrin. The complexation behaviour of cucurbit[6]uril was revealed in the ESR spectra of the nitroxides in the presence and in the absence of the host molecules, recorded at low temperatures. The experiments revealed that the mobilities of the nitroxides investigated are higher in the absence of the host molecule, a different behaviour compared with complexes with cyclodextrins. This behavior can be understood by taking into account the role played by the presence of salts necessary to ensure the solubility of cucurbit[6]uril in water.

Starting from dansyl-chloride, in reaction with 1,1-diphenylhydrazine and methoxyamine, two new fluorescent derivatives 1 and 2 were obtained and characterized by NMR, IR, UV-Vis, HR-MS, and fluorescence spectroscopy. The single-crystal X-ray structure was obtained for compound 2. Both compounds generate free radicals by oxidation, as demonstrated by ESR spectroscopy. Compound 1 generates the corresponding hydrazyl-persistent free radical, evidenced directly by ESR spectroscopy, while compound 2 generates in the first instance the methoxyaminyl short-lived free radical, which decomposes rapidly with the formation of the methoxy radical, evidenced by the ESR spin-trapping technique. By oxidation of compounds 1 and 2, their fluorescence is quenched.

Four new d10 heterometallic coordination polymers have been obtained using three Schiff-base ligands, zinc(II) nitrate, and dicyanometallates: 1∞[{Zn3(Salen)2}{μ-Au(CN)2}2] (1); 1∞[Zn(Saldmen){μ-Ag(CN)2}]·2H2O (2); 1∞[Zn(Salampy){μ-Ag(CN)2}] (3); 1∞[Zn(Salampy){μ-Au(CN)2}] (4). The Schiff bases are obtained from condensation of salicylaldehyde with ethylenediamine (H2Salen); N,N-dimethyl-ethylenediamine (HSaldmen) and, respectively, 2-aminomethyl-pyridine (HSalampy). The dicyanometallates are K[Ag(CN)2] and K[Au(CN)2]. The compounds were characterized by X-ray single-crystal diffraction, infrared spectroscopy, UV–vis spectroscopy, and elemental analysis. In compound 1, the homotrimetallic units, {Zn3(salen)2}2+, are connected by two [Au(CN)2]− bridges, forming a 1-D double chain. In compounds 2–4, the crystal structures show polymeric zigzag chains generated by the mononuclear zinc(II) nodes and [M(CN)2]− spacers. The luminescence properties of the new heterometallic polymers have also been investigated.

Four new coordination polymers have been obtained solvothermally from the reactions of Zn(NO3)2·6H2O with 1,2-, 1,3-, or 1,4-benzedicarboxylic acids in the presence of various amino-alcohols: 1∞[Zn2(Htea)2(1,2-bdc)] (1), 1∞[Zn(H3tris)(1,3-bdc)(CH3OH)] (2), 3∞[Zn5(Htea)2(1,3-bdc)3(H2O)]·2.6H2O (3), and 3∞[Zn3(H2dea)2(1,4-bdc)3] (4) (H3tea = triethanolamine, H3tris = tris(hydroxymethyl)aminomethane, H2dea = diethanolamine, 1,2-H2bdc =1,2-benzenedicarboxylic acid, 1,3-H2bdc =1,3-benzenedicarboxylic acid, and 1,4-H2bdc =1,4-benzenedicarboxylic acid). Their crystal structures, thermogravimetric analyses, solid-state transformation to ZnO and characterization of the resultant zinc oxide particles are reported. Compounds 1 and 2 show three-dimensional (3D) supramolecular architectures, generated from the interconnection of the zigzag (in 1) and respectively the linear (in 2) chains through hydrogen bonding interactions. The crystal structure of 3 revealed the presence of five different types of zinc atoms that a...

Two original heterooctanuclear [Ni(4)(II)Ln(4)(III)] complexes (Ln(III) = Sm-III, Gd-III) have been obtained starting from the [Ni-II(valpn)(H2O)(2)] mononuclear precursor [H(2)valpn = 1,3-propanediylbis(2-iminomethylene-6-methoxy-phenol)] and the corresponding lanthanide nitrates, in the presence of azide anions, through slow capture of atmospheric CO2. Three weak and competitive exchange interactions, J(GdGd), J(GdNi), J(NiNi), make the ground state of this magnetic system degenerate at cryogenic temperature and zero field. This, along with the high spin of Gd-III, lead to a significant magnetocaloric effect spread in the temperature range 1 to 20 K (Delta S-m[0-7 T, 3.5 K] = 19 J kg(-1) K-1).

Four new heterometallic 3d–4f complexes have been obtained using bi- and trinuclear building blocks: 1∞[Ni(L1)Gd(NO3)3(azbbpy)]·CH3CN (1), [Zn(L1)Eu(NO3)3(azbbpy)]·H2O (2), 1∞[(CuL2)2Gd(NO3)2(dca)] 3 and 1∞[(NiL2)2Dy(H2O)4(oxy-bbz)]NO3·3H2O (4), [H2L1 = 1,3-propanediyl-bis(2-iminomethylene-6-methoxyphenol), H2L2 = 2,6-di(acetoacetyl)pyridine, azbbpy = 1,3-bis(4-pyridyl)azulene, dca− = dicyanamide anion, and oxy-bbz = the dianion of the 4,4′-oxy-bis(benzoic) acid]. 1 and 2 represent the first complexes containing 1,3-bis(4-pyridyl)azulene as a ligand. 1, 3, and 4 are one-dimensional coordination polymers constructed from heterometallic nodes connected by the exo-dentate ligands. Helical chains are assembled in the case of 4. The analysis of the packing diagram for 1 reveals the occurrence of π–π stacking interactions established between the azulene rings from neighboring chains, which lead to supramolecular layers. The magnetic properties of 3 in the temperature range 1.9–300 K have been investigated. Intra-node ferromagnetic interactions are established between the CuII and GdIII ions (J = +2.7 cm−1, Ĥ = −J(ŜCu·ŜGd + ŜCu·ŜGd).

The polynuclear compounds containing anisotropic metal ions often exhibit efficient barriers for blocking of magnetization at fairly arbitrary geometries. However, at variance with mononuclear complexes, which usually become single-molecule magnets (SMM) under the sole requirement of a highly axial crystal field at the metal ion, the factors influencing the SMM behavior in polynuclear complexes, especially, with weakly axial magnetic ions, still remain largely unrevealed. As an attempt to clarify these conditions, we present here the synthesis, crystal structures, magnetic behavior, and ab initio calculations for a new series of Ni

Direct atmospheric CO2 capture occurred during the reactions of triphenyltin chloride (Ph3SnCl) with 1,2-bis(4-pyridyl)ethane (bpa) in methanol and aqueous ammonia. Depending on the reaction temperature, 4 °C and room temperature, two different compounds were obtained: a discrete, trinuclear complex, [(Ph3SnCl)2(μ3-CO3)(Ph3Sn)(Hbpa)]·H2O (1), and a coordination polymer 1∞[(Ph3SnCl)(Ph3Sn)2(μ3-CO3)(bpa)]·H2O (2), respectively. X-Ray crystal structure analysis reveals that both compounds contain a rare trinuclear carbonato-centered core C(OSnPh3)3. The supramolecular architecture of compound 1, assembled by hydrogen-bond interactions, is described.

Two novel bidimensional coordination polymers, [Co(azbbpy)(4,4'-bipy)0.5(DMF)(NCS)2]·MeOH (1) and [Co(azbbpy)(bpe)0.5(DMF)(NCS)2]·0.25H2O (2), resulted from the assembling of cobalt(II) ions by 1,3-bis(4-pyridyl)azulene, using either 4,4'-bipyridyl or 1,2-bis(4-pyridyl)ethylene as neutral spacers. The cobalt(II) nodes in 1 and 2 act as single-ion magnets (SIMs).

Six binuclear alkoxo-bridged complexes have been obtained and cystallographically characterized. The binuclear species are spontaneously assembled by reacting copper perchlorate with an aminoalcohol (monoethanolamine, Hmea, or propanolamine, Hpa) in the presence of various co-ligands: 4-phenyl-pyridine (4-phpy) 4-amino-pyridine (4-apy) dipyridylamine (dpyam), 2,3-bis(2-pyridyl)pyrazine (dpp). The six new compounds have the following formulas: [Cu(mea)(4-phpy)(ClO4)]2 1, [Cu(pa)(4-phpy)2]2(ClO4)2 2, [Cu(pa)(4-apy)(ClO4)]2 3, [Cu(mea)(dpyam)]2(ClO4)2 4, [Cu(pa)(dpyam)]2(ClO4)2 5, and [Cu(mea)(dpp)]2(ClO4)2·CH3OH 6. Except compound 1, the binuclear entities in crystals 2 – 6 are centrosymmetric, with pentacoordinated copper ions. In compound 1, one copper is pentacoordinated, while the other one is hexacoordinated. The perchlorate ions play different functions (monodentate and bridging in 1, monodentate in 3, uncoordinated in 2, 4, 5 and 6. The magnetic properties of compound 1 have been investigated and reveal a quite strong ferromagnetic coupling between the copper ions (J = + 81.9 cm−1, H = −JS1S2).

Three new complexes have been obtained using C3-symmetric trinuclear complexes as tectons; [Cu3(felden)(NCS)3(dmf)3] (1), [Cu3(felden)(mand)3]·(C2H5)2O (2), and [Cu3(felden)(dca)3(C2H5OH)]·2H2O (3) (H3felden is the Schiff base resulting from the condensation of 2,4,6-triformylphloroglucinol with N,N-dimethylethylenediamine, mand− is the anion of the R-mandelic acid and dca− is the dicyanamide anion). Compounds 1 and 2 are discrete trinuclear species, while compound 3 is a 2D coordination polymer, constructed from trinuclear nodes and dicyanamido spacers. The variable-temperature magnetic properties of 1–3 have been investigated and they reveal the occurrence of weak antiferromagnetic interactions between the copper(II) ions (−J values ranging from 0.90 to 2.40 cm−1) whose size and trend are dependent on the intramolecular copper–copper separation and nature of the basal chromophore at each copper atom.

We report the synthesis, structure, and spectroscopic and dynamic magnetic properties of a series of heterodinuclear complexes, [ZnLn(LH4 )2 ](NO3 )3 ⋅6 H2 O (Ln=Nd, Tb, Dy, Ho, Er, and Yb), with the singly deprotonated form of a new compartmentalized Schiff-base ligand, LH5 . The Ln(III) ions in these systems show a distorted square-antiprism geometry with an LnO8 coordination sphere. EPR spectroscopy and DC magnetic studies have shown that the anisotropic nature of the complexes is far more complicated than predicted on the basis of a simple electrostatic model. Among the investigated systems, only the Dy(III) derivative showed single-ion magnet behavior, in zero and an applied magnetic field, both in pure polycrystalline samples and in a series of polycrystalline samples with different degrees of dilution at the single-crystal level in the isostructural Y(III) derivative. The rich dynamics observed as functions of frequency, field, and temperature reveals that multiple relaxation mechanisms are at play, resulting in a barrier of 189 cm(-1) , which is among the highest reported for a dinuclear Zn-Dy system. Analysis of the dynamic behavior as a function of dilution degree further evidenced the persistence of non-negligible intermolecular interactions, even at the lowest concentration of 1 %.

New tetranuclear compounds have been obtained by reacting binuclear complexes, [Zn2L n (μ-OH)(H2O)2](ClO4)2, with sodium dicyanamide (HL n are end-off bicompartmental ligands resulting from condensation between 2,6-diformyl-p-cresol with N,N-dimethyl-ethylenediamine or 2-aminomethyl-pyridine). The complexes, [{L1(μ-OH)Zn2}(μ 1,5-dca)2{Zn2(μ-OH)L1}](ClO4)2 (1) and [{Zn2L2(μ 3-OH)(dca)}2](ClO4)2 · 2H2O (2), have been characterized by single-crystal X-ray diffraction. The angular nature of the bridging dicyanamido induces the “M” shape of the tetranuclear cationic unit in 1. The tetranuclear cation, because of its particular shape, acts as a receptor toward one perchlorate ion, which is hydrogen bonded to the hydroxo groups. This tetranuclear unit in 2 has a defective heterocubane structure. The luminescence properties of the new tetranuclear complexes have been investigated.

International audience; Five new Cu-II-Ag-I, Cu-II-Cu-I, and Zn-II-Au-I complexes have been obtained starting from copper(II) and, respectively, zinc(II) complexes with (NNO) Schiff-base ligands: [{(H2O)(saldmen)Cu}-{(NC)Ag(CN)}] 1, (1)(infinity)[{Cu-2(salaepipH)(2)(mu-CN)}{mu-[Ag(CN)(2)]}]-(ClO4)(2)center dot 4H(2)O 2, (1)(infinity)[{(salaepy)-Cu}{mu-[Ag(CN)(2)]}] 3, (1)(infinity)[{(salaepy)-Cu}{mu-[Cu(CN)(2)]}] 4, [(salaepy)Zn-NCAuCN](2)center dot H2O 5. The Schiffbase ligands (Hsaldmen, Hsalaepip, Hsalaepy) have been obtained by reacting the salicylaldehyde with N,N-dimethyletylenediamine, N-(2-aminoethyl)piperazine, and, respectively, 2-(2-aminoethyl)-pyridine. The structures of compounds 1 and 5 consist of discrete bi- and, respectively, tetranuclear species. The analysis of the packing diagram for crystal 1 reveals the formation of supramolecular double chains sustained by hydrogen-bond interactions involving the aqua ligand. Compounds 2, 3, and 4 are one-dimensional coordination polymers. The structure of 2 consists of chains constructed from {Cu(salaepip)} nodes bridged alternatively by [Ag(CN)(2)](-) and CN- ions, resulted from the partial decomposition of the silver complex. The 3-D architecture of the crystal is constructed from 1-D coordination polymers, [{Cu-2(salaepipH)(2)(mu-CN)}{mu-[Ag(CN)(2)]}](n)(2n+), which are connected by three water molecules that form a triangular water cluster, resulting in a scaffold-like structure with large channels. Compounds 3 and 4 are similar. Their structures can be described as resulting from zigzag anionic chains, [M(CN)(2)](n)(n-) (M = Ag-I or Cu-I), with three-coordinated silver(I) or copper(I) ions, to which monocationic complexes, {(salaepy)Cu}, are attached. The cryomagnetic properties of compounds 1 and 2 have been investigated. Weak antiferromagnetic interactions (J = -2.8 cm(-1), H = -jS(1)S(2)) mediated by hydrogen bonds are observed for compound 1. The cyanido bridge connecting the basal coordination sites of two copper(II) ions in 2 mediates a moderate antiferromagnetic coupling (J = 55.2 cm(-1)). Compound 5 exhibits blue luminescence (lambda = 464 nm, lambda(ex) = 400 nm).

Two different coordination polymers are obtained from d10 metal ions [Zn(II) and Cd(II)] and N,N′-ethylenebisacetamide (EBA). {[Zn(EBA)1.5(NO3)] · (NO3)} n (1) is a 1-D coordination polymer assembled from zinc ions and EBA molecules acting as a bridging ligand. Cd(H2O)2Cl2(EBA) (2) is constructed from 1-D inorganic polymeric chains {Cd(OH2)2Cl2} n and uncoordinated N,N′-ethylenebisacetamide molecules. These chains are interconnected through hydrogen bonds resulting in a 3-D supramolecular network. The luminescent properties of the organic molecule EBA, as well as of the coordination polymers 1, and 2 have been investigated.

Herein, we report the synthesis, structural investigation, and magnetic and photophysical properties of a series of 13 [Zn(II)Ln(III)] heterodinuclear complexes, which have been obtained employing a Schiff-base compartmental ligand derived from o-vanillin [H(2)valpn = 1,3-propanediylbis(2-iminomethylene-6-methoxy-phenol)]. The complexes have been synthesized starting from the [Zn(valpn)(H(2)O)] mononuclear compound and the corresponding lanthanide nitrates. The crystallographic investigation indicated two structural types: the first one, [Zn(H(2)O)(valpn)Ln(III)(O(2)NO)(3)], contains 10-coordinated Ln(III) ions, while in the second one, [Zn(ONO(2))(valpn)Ln(III)(H(2)O)(O(2)NO)(2)]·2H(2)O, the rare earth ions are nine-coordinated. The Zn(II) ions always display a square-pyramidal geometry. The first structural type encompasses the larger Ln ions (4f(0)-4f(9)), while the second is found for the smaller ions (4f(8)-4f(11)). The dysprosium derivative crystallizes in both forms. Luminescence studies for the heterodinuclear compounds containing Nd(III), Sm(III), Tb(III), Dy(III), and Yb(III) revealed that the [Zn(valpn)(H(2)O)] moiety acts as an antenna. The magnetic properties for the paramagnetic [Zn(II)Ln(III)] complexes have been investigated.

The self-assembly processes between binuclear [Zn2Ln]2+ complex cations and complex anions, [M(CN)2]− [M(I) = Ag(I), Au(I)], generate new one-dimensional (1-D) coordination polymers: 1∞[{L1Zn2(μ3-OH)}2(H2O){μ-[Ag(CN)2]}](ClO4)3 THF 0.5MeOH 1, 1∞[{L1Zn2(μ3-OH)}2(H2O){μ-[Au(CN)2]}](ClO4)3 THF H2O 2, 1∞[{L2Zn2(μ-OH)}{μ-[Ag(CN)2]}][Ag(CN)2] H2O 3 (H2Ln are bicompartmental Schiff-base ligands resulting from condensation reactions between 2,6-diformyl-p-cresol with 2-aminomethyl-pyridine, and 2-aminoethyl-pyridine, respectively). The luminescence properties of the new heterometallic complexes have been investigated.

International audience; The synthesis and crystal structures of five radical cation salts based on the organic donors bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF), racemic ethylenedithio-methyl-oxazoline-tetrathiafulvalene (EDT-TTF-MeOx) and the enantiopure (S,S,S,S) and (R,R,R,R) tetramethyl-bis(ethylenedithio)tetrathiafulvalene (TMBEDT-TTF) and the D3-symmetric anion tris(tetrachlorobenzenediolato)phosphate(V) (TRISPHAT) are reported. The salts are formulated as [BEDT-TTF][(rac)-TRISPHAT]·CH2Cl2 (1), [BEDT-TTF][(rac)-TRISPHAT]·2CH3CN (2), [(rac)-EDT-TTF-Ox][(rac)-TRISPHAT]·CH3CN (3), [(S,S,S,S)-TMBEDT-TTF][(rac)-TRISPHAT]·2CH3CN (4), and [(R,R,R,R)-TMBEDT-TTF][(rac)-TRISPHAT]·2CH3CN (5). The donors are fully oxidized and self-assemble in dyads inserted in the channels generated by the packing of the TRISPHAT anions. Magnetic and EPR measurements performed on compounds 1 and 2 clearly indicate weak interactions within the dimers in compound 1, characterized by a very narrow line in the EPR spectrum, while the radicals are strongly coupled in compound 2.

Two copper(II) [2 × 2] grid-like complexes were synthesized and structurally characterized. Investigation of the magnetic properties showed for both the occurrence of intramolecular ferromagnetic interactions.

By employing the common precursor Na3[Fe(CN)5(NH3)]·3H2O in a new synthetic approach, the azidopentacyanoferrate(III) ion has been isolated and structurally characterized as (Ph4As)2[Na(H2O)4][Fe(CN)5(N3)] 1. In order to confirm its building block ability, compound 1 has been reacted with the mononuclear complex [Mn(valphen)(H2O)2]ClO4 (H2valphen represents the Schiff base resulting from the condensation of o-vanillin with 1,2-phenylenediamine in a 2:1 M ratio) to afford the new MnIII–FeIII heterometallic system [Mn(valphen)(H2O)2]2[(H2O)(valphen)Mn(μ-CN)Fe(CN)4(N3)]·8H2O 2. The crystal structure of compound 2 reveals a supramolecular assembly generated by [(H2O)(valphen)Mn(μ-CN)Fe(CN)4(N3)]2− dianions and discrete [Mn(valphen)(H2O)2]+ counterions. The dynamic magnetic measurements of compound 2 point to a slow relaxation of the magnetization.

An unprecedented pentanuclear hetero-bimetallic complex has been obtained by a self-assembling process between {Cu2L}2+ binuclear cationic units and [Mo(CN)8]4− anions. The compound with the formula [{C L}2(µ-NC)2MoIV(CN)6(CH3OH)1.5(H2O)0.5] · [{C L}2(µ-NC)2MoIV(CN)6(CH3OH)2] · 5H2O · 7.5CH3OH (1) (H2L = binucleating Schiff-base obtained by condensation of 2,6-diformyl-4-methylphenol with 1,3-propylenediamine), 1, crystallizes in P 1 triclinic space group and consists of two pentanuclear species, [{C L}2(µ-NC)2MoIV(CN)6(CH3OH)1.5(H2O)0.5] (A), [{C L}2(µ-NC)2MoIV(CN)6(CH3OH)2] (B) and solvent. In each unit, two {Cu2L}2+ cations are bridged by one octacyanidomolybdate, via two cis-cyanido groups. Non-covalent channel motifs are developed through a complex network of supramolecular interactions (hydrogen bonds, π–π stacking interaction) involving A and B units and lattice solvent molecules.

The self-assembly processes between binuclear [Zn2] and [Cu2] complex cations and exo-bidentate ligands [trans-4,4′-azo-pyridine (azpy), 4,4′-bipyridine (4,4′-bipy), 1,2-bis(4-pyridyl)ethane (bpeta...

A new Co II /Co III hexanuclear complex, [Co 4 II Co 2 III (dea) 2 (Hdea) 4 )(piv) 4 ](ClO 4 ) 2 ·H 2 O 1 , has been obtained by reacting cobalt(II) perchlorate, diethanolamine, and pivalic acid (H 2 dea = diethanolamine and piv = pivalato anion). The cobalt ions are held together by four μ 3 and four μ 2 alkoxo bridges as well as by four syn – syn carboxylato groups. The hexanuclear motif contains four Co(II) and two Co(III) ions. The {Co II 4 Co III 2 (μ 2 -O) 4 (μ 3 -O) 4 } core can be described as a four face-sharing monovacant and bivacant distorted heterocubane units. The cobalt(III) ions are hexacoordinated. Two of the cobalt(II) are hexacoordinated, while the two others are pentacoordinated with a bipyramidal stereochemistry. The magnetic properties of 1 have been investigated in the temperature range 1.9–300 K. Compound 1 exhibits an overall antiferromagnetic behaviour with a ground singlet spin state.

The synthesis, structural investigation, and photophysical properties of a new heterobinuclear complex, [Zn(H(2)O)(valpn)Eu(NO(3))(3)], are reported [H(2)valpn = 1,3-propanediylbis(2-iminomethylene-6-metoxy-phenol)]. In the absence of the antenna-type sensitization of europium emission at room temperature, the strongest metal-centered emission was obtained following excitation into the (7)F(0)-(5)D(2) transition at 535 nm. In contrast, at 80 K, the strongest emission of europium was obtained by exciting into the maximum of a high-intensity, low-lying ligand-to-metal charge-transfer band (LMCT) located at approximately 425 nm. The overall temperature-induced changes of the photophysical properties of europium were assigned to the relative location of the LMCT and (3)pi pi* ligand states to the europium excited levels. The results may explain the lack of the antenna effects reported for some of the europium complexes with this type of ligand.

Three new heterobimetallic 1D coordination polymers have been obtained by assembling the [Ni(bpca)2] complex, as a building block, with lanthanide cations: [{Ln(O2NO)(H2O)3}{Ni(bpca)2}](NO3)2·3H2O (Ln Gd 1; Tb 2; Dy 3). The three compounds are isostructural and their structure consists of infinite cationic chains with LnIII ions connected by [Ni(bpca)2] complexes acting as bridging bis-bidentate ligands. The charge of the chains is counterbalanced by uncoordinated nitrate ions. The LnIII ions display a coordination number of nine: four oxygen atoms from the carbonyl groups of the bpca ligands belonging to two {Ni(bpca)2} moieties, two oxygen atoms from a chelating nitrato ion and three water molecules. The magnetic investigation of the gadolinium derivative 1 revealed very weak intrachain NiII–GdIII-ferromagnetic interactions (θ = +0.15 K). The weak intrachain-exchange interactions, as well as the bad magnetic isolation of the chains in the crystals, preclude the single-chain magnet behaviour of compounds 2 and 3. The out-of-phase, χ″, signal observed with compounds 2 and 3 can be ascribed to the magnetic slow relaxation of the lanthanide ions (TbIII, DyIII).(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Ditopic bis(acylhydrazone) ligands, derived from the reactions of carbohydrazides with 2-phenylpyrimidine-4,6-dicarbaldehyde and designed for grid formation with octahedrally coordinating transition-metal ions, exhibit a varied coordination chemistry depending upon the degree of their deprotonation. The neutral acylhydrazones are relatively poor ligands and are seemingly involved in multiple, labile complexation equilibria varying with the solvent and the particular metal salt in solution; nevertheless, grid complexes of different forms can be isolated in the solid state. Although only limited study has been made of the singly deprotonated ligands, grid species appear to be much more readily isolated. With the doubly deprotonated ligands, grid formation is strongly favoured in both the solution and solid states. As a consequence, the grid structures form spontaneously in the presence of a base by self-assembly from their components without need to preform the ditopic ligands. Extensive structural studies have been carried out both to establish the grid structures and to analyse the nature of the supramolecular interactions possible for neutral and charged grid species. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Synthesis and single crystal X-ray structures of the first paramagnetic transition metal complexes containing chiral ethylenedithio-tetrathiafulvalene-oxazoline (EDT-TTF-OX) 1a–c and ethylenedithio-tetrathiafulvalene-thiomethyloxazoline 2 (EDT-TTF-(SMe)OX) ligands based on copper (II) and cobalt (II) are described. The racemic [EDT-TTF-OX][Cu(hfac)2] complex 3a crystallizes in the triclinic centrosymmetric space group P 1 ¯ , whereas the enantiopure counterparts 3b–c crystallize in the triclinic non-centrosymmetric space group P1. Cu(II) adopts a distorted square pyramidal coordination geometry, a much weaker Cu⋯STTF interaction also being identified. The same coordination pattern around Cu(II) is observed in the complex [(rac)-EDT-TTF-(SMe)OX][Cu(hfac)2] (4) in spite of the bidentate nature of the redox active ligand. DFT theoretical calculations afforded two equilibrium configurations for a corresponding model complex, in which the metal centre establishes secondary coordination either with one STTF or with the SMe group. The same ligand coordinates the cobalt (II) to afford the octahedral complex [(rac)-EDT-TTF-(SMe)OX][Co(hfac)2] (5). In all these novel complexes, the paramagnetic centres are structurally and magnetically isolated. Cyclic voltammetry measurements show the stability of the radical cation species.

Six new Cu(II)−M(I) complexes (M = Ag, Au) were synthesized to illustrate the role of the convolution of d10−d10 (aurophilic or argentophilic) and π−π stacking interactions in sustaining supramolecular solid-state architectures. Two types of supramolecular synthons are involved: a rectangular one, based on the aurophilic (argentophilic) interactions between the [M(CN)2]- spacers, and a linear one, relying upon π−π contacts between the aromatic ligands. The reactions between [Cu(acac)(BB)(H2O)](ClO4) complexes and K[M(CN)2] in a 2:1 molar ratio (BB = 2,2‘-bipyridine; 1,10-phenanthroline) lead to the following heterotrinuclear complexes: [{Cu(acac)(bipy)}2{Au(CN)2}](ClO4)·0.5CH3CN (1), [{Cu(acac)(bipy)}2{Ag(CN)2}](ClO4)·0.5CH3CN (2), [{Cu(acac)(phen)}2{Ag(CN)2}](ClO4) (3), and [{Cu(acac)(phen)}2{Au(CN)2}](ClO4) (4). The recrystallization of 4 from acetonitrile affords [{Cu(acac)(phen)}2{Au(CN)2}](ClO4)·0.5CH3CN (5), which is isomorphous with the compounds 1−3. By reacting [Cu(sal)(bipy)]ClO4 with K[Ag(CN)...