Inorganic Chemistry Communications (v.8, #12)

Contents List (iii-xi).

Transition metal-complexed catenanes and rotaxanes in motion: Towards molecular machines by Jean-Paul Collin; Valérie Heitz; Sylvestre Bonnet; Jean-Pierre Sauvage (1063-1074).
In the present review article, we will discuss a few examples of molecular machines elaborated from transition metal-containing catenanes and rotaxanes. After describing a fast-moving pirouetting rotaxane and a linear rotaxane dimer whose behaviour is reminiscent of muscles, we will mostly focus on light-driven machines, consisting of ruthenium(II)-complexed rotaxanes or catenanes as well as related non-interlocking compounds.In the course of the last decade, many dynamic molecular systems, for which the movements are controlled from the outside, have been elaborated. These compounds are generally referred to as “molecular machines”. Transition metal-containing catenanes and rotaxanes are ideally suited to build such systems. In the present review article, we will discuss a few examples of molecular machines elaborated and studied in Strasbourg. In the first section we will discuss an electrochemically driven system, consisting of a fast-moving pirouetting rotaxane. The second paragraph will be devoted to a linear rotaxane dimer whose behaviour is reminiscent of muscles, in the sense that it can be stretched or contracted, and in the rest of this review article, we will mostly focus on light-driven machines, consisting of ruthenium(II)-complexed rotaxanes or catenanes. For these latter systems, the synthetic approach is based on the template effect of an octahedral ruthenium(II) centre. Two 1,10-phenanthroline ligands are incorporated in an axis or in a ring, affording the precursor to the rotaxane or the catenane, respectively. Ru ( diimine ) 3 2 + complexes display the universally used 3MLCT (metal-to-ligand charge transfer) excited state and another interesting excited state, the 3LF (ligand field) state, which is strongly dissociative. By taking advantage of this latter state, it has been possible to propose a new family of molecular machines, which are set in motion by populating the dissociative 3LF state, thus leading to ligand exchange in the coordination sphere of the ruthenium(II) centre. Finally, the potential of the Ru(terpy)(phen) core in the frame of light-driven molecular machines will be briefly discussed.
Keywords: Catenanes; Rotaxanes; Molecular machines; Ruthenium;

Oxidation of solid gold in chloroform solutions of cetyltrimethylammonium bromide by Tom Mortier; André Persoons; Thierry Verbiest (1075-1077).
Solid gold can be effectively oxidized in concentrated chloroform solutions of cetyltrimethylammonium bromide with the aid of sonication, leading to the formation of cetyltrimethylammonium tetrabromo aurate. This process can be utilized as a very easy preparation method for creating gold colloids after adding a suitable reducing agent to the AuBr 4 - / CTA + in chloroform system.Oxidation of solid gold was studied in chloroform solutions of cetyltrimethylammonium bromide (CTAB). We observed that, upon sonication, solid gold is oxidized and cetyltrimethylammonium tetrabromo aurate is formed. The Br ions act as a nucleophile that lowers the reduction potential of gold and molecular oxygen from the air acts as an oxidant. Addition of hydrazine to the sonicated solution leads to the formation of gold nanoparticles dispersed in chloroform.
Keywords: Gold; Cetyltrimethylammonium bromide; Sonication; Nanoparticles;

The first Sm–Ni heterometallic complex with picolinic acid ligand has been synthesized, which displays the two-dimensional layered framework with the first reported basket weave topology; Studies on magnetic property indicate the existence of antiferromagnetic interactions for 1.The first basket weave framework topology of Sm–Ni heterometallic complex with picolinic acid as bridging ligand showing two different coordination modes of picolinic acid has been characterized; The studies on temperature-dependent magnetization indicate the title complex follows the Curie–Wiess paramagnetic behavior down to 5 K.
Keywords: Ln–Ni heterometallic complexes; Crystal structures; Magnetic properties; Topology;

Amine catalysed silicon–oxygen bond formation by Kaustavmoni Deka; Rupam Jyoti Sarma; Jubaraj B. Baruah (1082-1084).
Catalytic reaction of triethylenetetramine with silanes and silanols leads to new Si–O bond formationCatalytic amount of triethylenetetramine causes dehydration of diphenylsilanediol to form octaphenyltetrasiloxane, whereas, catalytic reaction of triethylenetetramine leads to dehydrogenative polymerisation of phenylsilane with various diols.
Keywords: Silanols; Silanes; Triethylenetetramine; Catalysis; Dehydration; Dehydrogenative polymerisation;

The dipeptide H-Aib-l-Ala-OH ligand in copper(II) chemistry: Variation of product identity as a function of pH by Manolis Tiliakos; Eugenia Katsoulakou; Aris Terzis; Catherine Raptopoulou; Paul Cordopatis; Evy Manessi-Zoupa (1085-1089).
The reaction between Cu(II) sources and the dipeptide H-Aib-l-Ala-OH (LH) is pH-dependent. In the “low pH” 3D coordination polymer {[CuClL](H2O)2.5} n , the monoanionic dipeptide behaves as a tridentate bridging N(amino), O(peptide), O(carboxylate) ligand, while the dianionic dipeptide exhibits the tetradentate bridging N(amino), N(peptide), O(carboxylate), O′ carboxylate behaviour in the “higher pH” 1D complex {[Cu(H−1L)(EtOH)](EtOH)} n .A systematic investigation of the influence of “pH” on the product identity from the CuII/H-Aib-l-Ala-OH (LH) reaction system is described, where H-Aib-l-Ala-OH is α-aminoisobutyryl-l-alanine. The pH variation has led to the synthesis of two discrete complexes, the structures of which have been determined by single-crystal X-ray crystallography. The “low pH” complex {[CuClL](H2O)2.5} n (1) is a 3D coordination polymer, in which the dipeptide monoanion L behaves as a η1112 ligand binding one CuII atom through its amino nitrogen and neutral peptide oxygen, and an adjacent CuII atom through one of its carboxylate oxygen. The “higher pH” complex {[Cu(H−1L)(EtOH)](EtOH)} n (2) is a chain (1D) compound, in which the dipeptide dianion H−1L2− uses its amino nitrogen, deprotonated peptide nitrogen and both carboxylate oxygens to bridge two metal centres.
Keywords: α-Aminoisobutyryl residue; Copper(II) complexes; Dipeptide complexes; X-ray crystal structures; Peptide bond coordination;

3D supramolecular network constructed by intermolecular interactions in mixed ligand complex of zinc by Danuta Dobrzyńska; Tadeusz Lis; Lucjan B. Jerzykiewicz (1090-1093).
3D supramolecular structure in the crystal of [Zn(quin-2-c)2(Him)2] is made by intermolecular interactions: N–H⋯O and C–H⋯O hydrogen bonds as well as the C–H⋯π and ππ type interactions. The vibrations of monodentate carboxylate group are severely influenced by strong hydrogen bond.New complex [Zn(quin-2-c)2(Him)2] (quin-2-c = quinoline-2-carboxylate ion, Him = imidazole) was synthesized by self assembly and its structure was determined by X-ray analysis. The compound crystallizes in P21/c space group. Four independent molecules of complex are present in the structure. Strong hydrogen bonds create three different 1D chains which are collected in two different layers. The alternately packed layers form the 3D supramolecular structure. The interchain and interlayer contacts are of the C–H⋯O, π⋯π and C–H⋯π type. The influence of strong hydrogen bond on the vibrational characteristics of the monodentately coordinated carboxylate group in zinc complexes with quin-2-c ion is discussed.
Keywords: Zinc complex; Crystal structure; Supramolecular network; Hydrogen bonds; Infrared spectra;

First discrete six-coordinate mercury (II) complex, Hg(η3-N4,N3,S-pytsc)2 1, having tridentate pyridine-2-carbaldehyde thiosemicarbazonate is reported.First discrete example of six-coordinate mercury (II) complex, Hg(η3-N4,N3,S-pytsc)21, with tridentate pyridine-2-carbaldehyde thiosemicarbazonate (pystc) anion having distorted trigonal prismatic geometry is described.
Keywords: Pyridine-2-carbaldehyde thiosemicarbazonate; Trigonal prismatic; Organomercury; Symmetrization;

A new type of supramolecular compound [Cu(salen)]4  · Na2[Cu(mnt)2] has been synthesized and characterized. The neutral [Cu(salen)] complexes assemble among themselves through π–π interactions that form an framework type arrangement having well-defined channels. The ionic inorganic complex Na2[Cu(mnt)2], that acts as a template in this salen based-assembly, is accommodated in the channel as a guest.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.
Keywords: Copper–Schiff-base complex; π–π-Assembly; Framework type material; Supramolecular chemistry; Templating effect; Dithiolate;

A new cyclometalated rhenium(I) ( CO ) 4 + complex by Rafał Czerwieniec; Andrzej Kapturkiewicz; Jacek Nowacki (1101-1104).
Reactions of Re(CO)5Cl with N ∩ C chelating ligand (2-phenyl-benzothiazole) afford neutral rhenium(I) tetracarbonyl Re(CO)4(N ∩ C) complex characterized by means of the X-ray diffraction, electrochemical and UV–Vis, IR and EI MS spectroscopic studies.Reaction of Re(CO)5Cl with 2-phenylbenzothiazole (HΦBT) afforded the cyclometalated Re(CO)4(ΦBT) complex with the molecular structure of the obtained product confirmed by X-ray investigations. Re(CO)4(ΦBT) shows intense, hardly dependent on environment, luminescence originating from the π–π* ΦBT intraligand electronic transition. The investigated Re(CO)4(ΦBT) complex can be considered as a potentially applicable “triplet emitter” for OLED devices.
Keywords: Rhenium; 2-Phenylbenzothiazole; Transition metal complexes; X-ray crystallography; UV–Vis spectroscopy;

A novel molecular solid, [OFBzIQl][Ni(mnt)2] (1), where [OFBzIQl]+  = 1-(2′-fluorobenzyl)isoquinolinium and mnt2−  = maleonitriledithiolate, forms 1D column of alternating between cations and anions via π⋯π stacking interaction between Ni(mnt)2 plane and isoquinoline ring, and exhibits a magnetic constant transition from ferromagnetic to antiferromagnetic around 35 K as the temperature is lowered.A novel molecular solid, [OFBzIQl][Ni(mnt)2] (1), where [OFBzIQl]+  = 1-(2′-fluorobenzyl)isoquinolinium and mnt2−  = maleonitriledithiolate, forms 1D column of alternating between cations and anions via π⋯π stacking interaction between Ni(mnt)2 plane and isoquinoline ring, and the Ni(mnt)2 anions between the adjacent columns exist short C⋯N interaction. The extensive hydrogen bonds between anions and cations in the crystal generate a 2D network structure. Magnetic susceptibility measurement for 1 in the temperature range 2.0–300 K shows that 1 exhibits a magnetic constant transition from ferromagnetic to antiferromagnetic around 35 K as the temperature is lowered.
Keywords: Maleonitriledithiolate; 1-(2′-Fluorobenzyl)isoquinolinium; Nickel(III) complex; Crystal structure; Magnetic properties;

A novel cationic Hg(II) complex has been synthesized with N-methyl-imidazolidine-2-selone ligand. The tris(N-methyl-imidazolidine-2-selone) mercury(II) complex, [(MeImSe)3HgCl]+Cl (1), has been characterized by single crystal X-ray analysis and CP MAS 199Hg and 77Se NMR.A novel cationic Hg(II) complex has been synthesized with N-methyl-imidazolidine-2-selone ligand. The tris(N-Methyl-imidazolidine-2-selone) mercury(II) complex, [(MeImSe)3HgCl]+Cl (1), has been characterized by single crystal X-ray analysis and CP MAS 199Hg and 77Se NMR.
Keywords: Crystal structure; CP MAS 199Hg NMR; 77Se NMR; N-methyl-imidazolidine-2-selone; Hg(II) complex;

Enhanced regioselectivity in palladium-catalysed asymmetric methoxycarbonylation of styrene using phosphetanes as chiral ligands by Bianca Muñoz; Angela Marinetti; Aurora Ruiz; Sergio Castillon; Carmen Claver (1113-1115).
The palladium-catalysed asymmetric methoxycarbonylation of styrene was studied using a series of phosphetanes as chiral ligands.The palladium-catalysed asymmetric methoxycarbonylation of styrene has been investigated for the first time using phosphetanes as chiral ligands and showed good catalytic activity, excellent regioselectivity to the branched product and enantioselectivity up to 29%.
Keywords: Palladium; Methoxycarbonylation; Asymmetric; Phosphetanes; Styrene;

Inter-conversion of single and double stranded 1-dimensional coordination polymers is demonstrated for the Ce–Sr–dipicH2 system.A solution of the previously known 1-D coordination polymer, made up of alternating [Ce(dipic)3]2− and [Sr(dipicH2)(OH2)3]2+ polyhedra takes up additional Ce4+ and Sr2+ ions leading to the double stranded hetero-metallic squarate chain. The transformation can be reversed by adding excess dipicH2. The crystal structure and thermal decomposition study of the new squarate chain polymer is reported. The analogous Ca compound does not undergo this transformation.
Keywords: Hetero-metallic coordination polymer; Inter-conversions; Crystal structure; Cerium(IV); Strontium(II);

Novel hetero-polymetallic derivatives of palladium bearing pyridylthioether fragments incorporating a Fe2(CO)6 cluster core as ligand by Luciano Canovese; Fabiano Visentin; Gavino Chessa; Claudio Santo; Paolo Uguagliati (1120-1124).
The complexation of poly(pyridylthioether) incorporating a Fe2(CO)6 cluster core with palladium derivatives in different oxidation states afforded novel hetero-polymetallic complexes.The complexation of poly(pyridylthioether) incorporating a Fe2(CO)6 cluster core with palladium derivatives in different oxidation states afforded novel hetero-polymetallic complexes.
Keywords: Palladium complexes; Hetero-polymetallic derivatives; Palladium(0); Palladium(II) complexes; Pyridylthioether polydentate ligands;

We report the application of the manganese μ-oxo porphyrins with electron-donating or electron-withdrawing substituents as active and selective catalysts for partial oxidation of cyclooctane to alcohol and ketone without reducing agent.Electron-donating or electron-withdrawing substituents at the porphyrin rings considerably increase the catalytic activity of the manganese monomeric and μ-oxo porphyrins in the oxidation of cyclooctane with molecular oxygen without the use of sacrificial co-reductant. The change in the catalytic activity is due to the nature and number of the substituents in the porphyrin ring.
Keywords: Metalloporphyrins; μ-oxo metalloporphyrins; Cyclooctane oxidation;

Ferromagnetic coupling dicyanamide-bridged dinuclear gadolinium(III) complex [Gd2(dca)4(OH)2(NITpPy)4] (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.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 μ1,5-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.
Keywords: Gadolinium(III) complex; Dicyanamide; Nitronyl nitroxide; Crystal structure; Magnetic properties;

Synthesis, crystal structure and NMR of [Na(DB18C6)(CH3CN)]3[α-AsM12O40] (M = Mo/W) by Xiaoming Lu; Bo Liu; Sarula; Jing Wang; Chaohui Ye (1133-1136).
Super-molecular complexes [Na(DB18C6)(CH3CN)]3[α-AsM12O40] (M = Mo/W), in which dibenzo-18-crown-6 and polyanion were linked by Na+, were obtained by solvothermal reaction and characterized by IR,1H 13C and gUMBC NMR, X-ray.Two super-molecular complexes [Na(DB18C6)(CH3CN)]3[α-AsM12O40] (M = Mo/W) were obtained by solvothermal reaction and characterized by IR,1H 13C and gUMBC NMR, X-ray. The result reveals that the complex consists of a [α-AsM12O40]3− (M = Mo/W) anion with α-Keggin structure, and three complex [Na (DB18C6)(CH3CN)]+ cations in which every sodium ion is located in the cavity of dibenzo-18-crown-6 with 6 Na–O bonds and coordinated with one of the terminal O atom of [α-AsM12O40]3− (M = Mo/W) and the N atom of CH3CN from two sides of the distorted DB18C6 plane, respectively. The three terminal O atoms linked with sodium ion are from a single M3O13 (M = Mo/W) triplet of the α-Keggin metalatoarsenate anion, and M–Ob (M = Mo/W) bonds exhibit alternating single–double bond character.
Keywords: Crown ether; Polyoxometalates; Crystal structure; Solvothermal reaction;

1D polymeric heptacoordinated cadmium(II) chain [Cd(bpfd)(μ1,3-NCS)(NCS)] n (1) which forms a 3D supramolecule through weak C–H…S hydrogen bonding and π…π interaction is prepared that shows intraligand 1(π–π*) fluorescence and 3(π–π*) phosphorescence.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)(μ1,3-NCS)(NCS)] n (1) which forms a 3D supramolecule through weak C–H…S hydrogen bonding and π…π interaction.
Keywords: Cadmium(II); Thiocyanate; Schiff base; 1D chain, C–H…S hydrogen bonding;

1,3,5-Triaza-7-phosphaadamantane (PTA) ligated iridium(I) complexes as catalysts for the intramolecular hydroamination of 4-pentyn-1-amine in water by Donald Alan Krogstad; Andrew J. DeBoer; William J. Ortmeier; Joseph W. Rudolf; Jason A. Halfen (1141-1144).
The water-soluble complex [Ir(COD)(PTA)3]Cl (1, COD = 1,5-cyclooctadiene, PTA = 1,3,5-Triaza-7-phosphaadamantane) was prepared by the reaction of [IrCl(COD)]2 with PTA and is only one of the two [Ir(COD)P3]+ complexes to be structurally characterized as a square-pyramidal species. 1 and the related compounds, [IrCl(CO)(PTA)3] (2) and [Ir(CO)(PTA)4]Cl (3), were found to be active catalysts for the intramolecular hydroamination reaction in water.The water-soluble complex [Ir(COD)(PTA)3]Cl (1, PTA = 1,3,5-triaza-7-phosphaadamantane) was prepared by the reaction of [IrCl(COD)]2 with six equivalents of PTA under a nitrogen atmosphere. Compound 1 was fully characterized in solution and the solid state. 1 crystallized in the monoclinic space group C2/c with a  = 29.648(9) Å, b  = 11.238(2) Å, c  = 19.930(2) Å, and β  = 96.55(2)°. Complex 1 and the related Ir(I) compounds, [IrCl(CO)(PTA)3] (2) and [Ir(CO)(PTA)4]Cl (3), were active catalysts in the intramolecular hydroamination of 4-pentyn-1-amine in water. This is the first reported study of the Ir(I) mediated transformation in aqueous media.
Keywords: Water; Phosphine; Iridium; 1,3,5-Triaza-7-phosphaadamantane; Intramolecular hydroamination;

A new three-dimensional Cu(II) coordination polymer with triaminoguanidin building blocks by Aksana Zharkouskaya; Helmar Görls; Gavin Vaughan; Winfried Plass (1145-1148).
Two interpenetrating networks of the trinuclear copper(II) building blocks are formed in the three-dimensional metal-organic framework. The magnetic properties are dominated by the spin frustrated building blocks represented as nodes in the depicted networks.The reaction between the tris(2-hydroxybenzylidene)triaminoguanidin hydrochloride (H6L)Cl and copper(II) chloride in the presence of triethylamine leads to a three-dimensional coordination polymer with two interpenetrating (10,3)-a networks of opposite chirality. Magnetic studies revealed strong antiferromagnetic coupling between copper ions of the spin frustrated trinuclear building unit.
Keywords: Coordination polymer; Copper(II) complex; Crystal structure; Magnetic properties; Self-assembly;

Cost efficient preparation of lead aminoalkoxides directly from lead(II) oxide by Tim Kemmitt; Liliane G. Hubert-Pfalzgraf; Graeme J. Gainsford; Philippe Richard (1149-1153).
Chelating aminoalkoxides of lead were prepared directly from the reaction of lead (II) oxide with dimethylaminoethanol (dmaeH), N-methyldiethanolamine (mdeaH2), and triethanolamine (teaH3) in refluxing toluene. The compounds are free of inorganic counterions, making them potentially useful as metal-organic precursors for thin film oxides.The preparation of lead(II) aminoalkoxides has been demonstrated from the direct reaction of aminoalcohols with lead(II) oxide. The denticity of the aminoalcohols determined the facility of the reactions, the rate increasing with the number of hydroxyls. Thus, [Pb(dmae)2], 1, [Pb(mdea)], 2, and [Pb(teaH)]2, 3 (dmaeH = dimethylaminoethanol, mdeaH2  =  N-methyldiethanolamine, and teaH3  = triethanolamine) have been prepared in high yields and characterized by 1H and 13C NMR. The X-ray crystal structure analyses of 2 and 3 are described.
Keywords: Lead; Amino alkoxides; Crystal structures; Sol–gel;

The RuCl3(dppb)H2O complex: A new metal-assisted oxidative dehydrogenation of the o-phenylenediamine ligand by Ana Lúcia R. Silva; Marcelo O. Santiago; Izaura C.N. Diógenes; Solange O. Pinheiro; Eduardo E. Castellano; Javier Ellena; Alzir A. Batista; Fábio B. do Nascimento; Ícaro S. Moreira (1154-1158).
Experimental results showed that the mer-[RuCl3(dppb)(H2O)] complex is a suitable precursor for the conversion of the o-phenylenediamine to o-benzoquinonediimine ligand in a reaction sensible to the oxygen presence. This observation points for the application possibility of the mer-[RuCl3(dppb)(H2O)] aqua-complex as starting reagent in a wide range of synthetic routes.The trans-[RuCl2(dppb)(bqdi)] and trans-[RuCl2(dppb)(opda)] complexes (dppb = 1,4-bis(diphenylphosphine)butane, bqdi =  o-benzoquinonediimine, and opda =  o-phenylenediamine) were synthesized from the reaction of the mer-[RuCl3(dppb)(H2O)] aqua-complex with the opda ligand. The X-ray structural and electrochemical characterizations of the isolated compounds showed that this aqua-complex induces the oxidative dehydrogenation of the amine species (opda) to the imine form (bqdi) of the o-phenylene ligand during the synthetic procedure. In the presence of oxygen, the 31P{1H} NMR experiments confirmed that the trans-[RuCl2(dppb)(bqdi)] complex is the only product formed.
Keywords: Ruthenium complexes; 1,4-Bis(diphenylphosphine); o-Phenylene ligands; X-ray structures;

Phenylcalcium iodide is accessible via direct synthesis and cleaves THF above −20 °C under formation of the title compound. For the first time, an example of a heavy Grignard reagent and an arylcalcium derivative was characterized by X-ray crystallography. The phenyl substituents (gray) and the iodine atoms (purple) are in bridging positions between calcium atoms (yellow), which form a distorted Ca4 tetrahedron (red oxygen). (For interpretation of the references to colour in this figure, the reader is referred to the Web version of this article.)Phenylcalcium iodide is accessible by direct synthesis from activated calcium and iodobenzene in THF at low temperatures. The use of chloro- or bromobenzene as well as of another solvent such as diethylether lowers the yield significantly. Phenylcalcium iodide cleaves THF already at −20 °C under formation of benzene. From this reaction solution single crystals of the title compound precipitate. The central structural fragment consists of a distorted calcium tetrahedron, centered by an oxygen atom and with Ca atoms being bridged by phenyl groups (average Ca–C 257 pm) and iodide ligands.
Keywords: Calcium; Direct synthesis; Grignard reagents; Organocalcium compounds; Phenylcalcium iodide;

Synthesis and structure of the cadmium(II) complex of [CdII(CEAP)2(H2O)(CH3COO)Cl] {CEAP = 4-[N,N-bis(2-cyanoethyl)]amino-pyridine} has been reported. The structure exhibits a novel 3D-cagework assembly with the assistance of the coordinated chloride anion and water molecule via forming multiple hydrogen bonds with the cyanoethyl arms of CEAP.Synthesis and structure of the cadmium(II) complex of [CdII(CEAP)2(H2O)(CH3COO)Cl] {CEAP = 4-[N,N-bis(2-cyanoethyl)]aminopyridine} has been reported. The structure exhibits a novel 3D-cagework assembly with the assistance of the coordinated chloride anion and water molecule via forming multiple hydrogen bonds with the cyanoethyl arms of CEAP.
Keywords: Cyanoethyl derivative; Cadmium complex; Weak interaction; Self-assembly;

Two novel zinc compounds with nicotinate derivatives, [Zn(Enic)2] n and [Zn(H2O)6][6-OHnic]2, have been synthesized under hydrothermal reaction conditions. The X-ray single-crystal analysis reveals that the structure of the compound 1 is self-assembled from square-grid nets stacked via interdigitation while compound 2 forms a 3D supermolecular network structure via strong O–H⋯O hydrogen bond.Two novel zinc compounds [Zn(Enic)2] n (1) (Enic = 5-ethylnicotinate) and [Zn(H2O)6][6-OHnic]2 (2) (6-OHnic = 6-hydroxynicotinate) have been synthesized under hydrothermal reaction conditions. The structure of the compound 1 is self-assembled from square-grid nets stacked via interdigitation while compound 2 forms a 3D supermolecular network structure via strong O–H⋯O hydrogen bond. In addition, the luminescent properties of two compounds were investigated in the crystalline state.
Keywords: Zinc coordination polymer; Hydrothermal reaction; Interdigitation; O–H⋯O hydrogen bond; Luminescence;

In a novel {[Cu(dca)(pcl)(H2O)]2} n supramolecular complex, constructed by hydrogen-bond interactions and weak Cu–N bond interactions, strong antiferromagnetic interactions exist between two Cu(II) ions of the dca-bridged dimer.A dicyanamide (dca) Cu(II) supramolecular complex constructed by hydrogen-bond interactions and weak Cu–N bond interactions has been prepared and the structure was determined by X-ray diffraction analysis. The magnetic studies indicate that strong antiferromagnetic interactions exist between two Cu(II) ions of the dca-bridged dimer.
Keywords: Dicyanamide; Supramolecule; Crystal structure; Magnetic material;

Synthesis and structure of [ 18 - MC Cu II ( N ) pko - 6 ] 6 + : A new member of anion encapsulating metallamacrocyles by Tereza Afrati; Catherine Dendrinou-Samara; Curtis M. Zaleski; Jeff W. Kampf; Vincent L. Pecoraro; Dimitris P. Kessissoglou (1173-1176).
The 18-metallacrown-6 complex with a repeat unit of –[Cu–N–O]6– encapsulates a perchlorate anion in the solid state. Pyridyl rings from the ligand form a cavity above (dark color) and below (light color) the metallacrown ring and help to encapsulate the perchlorate anion.The reaction of copper(II) perchlorate with di-2-pyridyl ketone oxime yields the first 18-MC-6 complex with M–N–O connectivity, [Cu6(pko)6ClO4(CH3CN)6] [Cu6(pko)6(ClO4)3(CH3CN)4] · 8ClO4  · 14CH3CN · H2O 1. In the solid state the cationic complex encapsulates a perchlorate anion within the central cavity. Magnetic susceptibility measurements reveal that the complex is diamagnetic. EPR measurements indicate that the complex dissociates in DMF.
Keywords: Metallamacrocycle; Copper complex; Crystal structure;

The reactions of K2OsCl6 with 1,2-bis(diphenylphosphino)-ethane (dppe) afford neutral Os(dppe)(dppeO)(CO)Cl2 product – active intermediate in the synthesis of strongly luminescent osmium(II) complexes.Reaction of K2OsCl6 with 1,2-bis(diphenylphosphino)ethane (dppe) in 1:2 ratio afforded the osmium(II) Os(dppe)(dppeO)(CO)Cl2 complex (where dppeO = 1,2-bis(diphenylphosphino)ethane monoxide) with the molecular structure confirmed by X-ray investigations. The Os(dppe)(dppeO)(CO)Cl2 intermediate can be simply converted to Os ( dppe ) ( N ∩ N ) ( CO ) Cl + ⋯ PF 6 - species in reaction with N ∩ N chelating diimines like 1,10-phenanthroline, 4,7-diphenyl-1,10-phenanthroline or 3,4,7,8-tetramethyl-1,10-phenanthroline. The obtained mixed Os ( P ∩ P ) ( N ∩ N ) ( CO ) Cl + ⋯ PF 6 - complexes feature strong (with ϕ em up to 0.57) long lived (with τ em up to 25.2 μs) MLCT emission.
Keywords: Osmium complexes; X-ray crystallography; 31P NMR spectroscopy; UV–Vis absorption and emission spectra;

In situ complexation of copper(II)sulphate and pyridine-2-carboxaldehyde oxime formed catalytically active complex for the oxidation of veratryl alcohol in alkaline aqueous solution. The structure of the active species in the reaction solution and the solid state structure of Cu(PAO)2SO4 were determined.In situ generated [CuII(pyridine-2-carboxaldehyde oxime)2] complex catalyses selective oxidation of veratryl alcohol (3,4-dimethoxybenzyl alcohol) to aldehyde by molecular oxygen in aqueous solution. Under alkaline conditions, the catalyst has both oxime groups deprotonated and the solid state structure of the complex reveals a square pyramidal geometry established by two pyridine-2-carboxaldehyde oxime ligands and sulphate as a counter anion.
Keywords: Catalytic oxidation; Copper; Pyridine-2-carboxaldehyde oxime; Molecular oxygen;

The complex trichloro(phenylazo)-bis(triphenylphosphine)-ruthenium(II) shows a longest-wavelength absorption at λ max  = 520 nm which is assigned to a Ru(II) → phenyldiazonium+ MLCT transition. MLCT excitation leads to the oxidation of the metal and reduction of the diazonium cation which decays to nitrogen and phenyl radical.The complex trichloro(phenylazo)bis(triphenylphosphine)ruthenium(II) shows a longest-wavelength absorption at λ max  = 520 nm which is assigned to a Ru(II) → phenyldiazonium+ MLCT transition. MLCT excitation leads to the oxidation of the metal and reduction of the diazonium cation which decays to nitrogen and phenyl radical.
Keywords: Electronic spectra; MLCT; Photochemistry; Ruthenium; Phenyldiazonium;