Synthesis and Structure of New Dimeric Cyclopentadienyl Titanium Fluorine–Oxygen Systems: [Cp*TiF(μ-F)(μ-OPOPh2)]2, [Cp*TiF(μ-F)(μ-OSO2-p-C6H4Me)]2 and [Cp*TiF2(μ-OMe)]2

The reactions of Cp*TiF₃ with Me₃SiOPOPh₂, Me₃SiOSO₂-p-C₆H₄Me, and Al(OMe)₃ resulted in the formation of the dimers [Cp*TiF(μ-F)(μ-OPOPh₂)]₂ 1 , [Cp*TiF(μ-F)(μ-OSO₂-p-C₆H₄Me)]₂ 2 , and [Cp*TiF₂(μ-OMe)]₂ 3 , respectively, in good yields. In contrast to the formation of 3 , Cp*TiF₃ reacts with Al(OH)₃ to afford the known tetramer [Cp*TiF(μ-O)]₄ 4 . The structures of 1–3 have been determined by X-ray crystallography; compounds 1 and 3 crystallize in the monoclinic space group P2₁/c and compound 2 in the monoclinic space group P2/n. Compound 1 is the first example of a dimeric Cp*-titanium phosphinate containing a fluorine ligand. The core of the dimeric structure of both 1 and 2 consists of two Ti atoms bridged by two fluorine atoms and two bidentate groups. In contrast, the dimeric structure of 3 consists of two Ti atoms bridged only by two methoxy groups. An equilibrium of isomers of 1 and 2 has been observed in solution by ¹H and ¹⁹F NMR. The ¹⁹F NMR spectra of 1–3 are discussed in detail.     

Synthesis and structure of the pentanuclear mixed-metal cluster [Co4MoCp(μ3-SBut)(μ3-S)(μ3-CO)(μ-CO)2(CO)6]

The pentanuclear mixed-metal cluster [Co₄MoCp(μ₃-SBu^t)(μ₃-S)(μ₃-CO)(μ-CO)₂(CO)₆] (1) has been synthesised by reaction of [CoMoCp(CO)₇] with Bu^tSSBu^t. X-ray structural analysis identified an asymmetric unit with three cobalt atoms and one molybdenum forming an irregular tetrahedron while one cobalt–molybdenum edge is bridged by a cobalt atom. Crystal data: space group P2(1)/n, a=10.162(2), b=13.722(3), c=17.69(5) Å, β=91.44(2)°, Z=4.     

Synthesis,structure, and catalytic activity of a new chiral NHC–iridium(III) complex

The new chiral NHC–iridium complex 3 has been prepared in CH₃CN from the reaction between [Ir(COD)Cl]₂, NaOAc, KI, and dibenzimidazolium salt 2 which is derived from (S)-2,2′-diamino-6,6′-dimethyl-1,1′-biphenyl. Complex 3 has been characterized by various spectroscopic techniques, elemental analyses, and X-ray diffraction analysis. It has a distorted-octahedral IrC₂N₂IH core structure, and shows good catalytic activity for the asymmetric hydrosilylation of arylmethyl ketones, leading to 1-arylethanol with moderate ee values.     

A novel 3D coordination polymer [Cd15(μ4-Mtta)12(μ3-Mtta)6(μ3-SO4)4(μ3-OH)4]: Synthesis,structure and solid properties

A 3D coordination polymer, {[Cd₁₅(μ₄-Mtta)₁₂(μ₃-Mtta)₆(μ₃-SO₄)₄(μ₃-OH)₄] · 6H₂O}_n (1) (Mtta = 5-methyl-tetrazolate), which shows the rare multifunction of in situ formed Mtta and bright photo-induced blue emission, was isolated from a hydrothermal reaction of CdSO₄ · 8/3H₂O, NaN₃ in acetonitrile and water.     

Synthesis,spectroscopic studies and structure prediction of the new Tb(3-NH2PIC)3·3H2O complex

The synthesis, spectroscopic properties and structure prediction of the complex of Tb(III) with 3-aminopyridine-2-carboxylic acid (3-NH₂PIC) are described. The complex was characterized by elemental analysis and IR, absorption and emission spectra. The C, H and N elemental analysis consistent with the formulation of the compound as Tb(3-NH₂PIC)₃·3H₂O. This complex exhibits a luminescence intensity that is attenuated to that of its Eu⁺³ congener. The Sparkle model, used for structural computations of lanthanide complexes (SMLC), was applied to the new complex. The calculation used an INDO/S-CI model for determination of the electronic spectrum.     

Binuclear rhodium(III) and iridium(III) monoselenocarboxylates: Synthesis,spectroscopy and structure of an ortho-metallated iridium complex featuring an IrCCC(μ-Se) chelate ring

Monoselenocarboxylate–bridged binuclear complexes of Rh^III and Ir^III, [(Cp1MCl)₂(μ-SeCOAr)₂] (1) (M = Rh or Ir; Cp1 = pentamethylcyclopentadienyl; Ar = Ph, C₆H₄Me–4), have been isolated either by the reaction between [Cp1₂M₂(μ-Cl)₂Cl₂] with KSeCOAr in acetonitrile or by treatment of [Cp1MCl(solvent)₂][PF₆] with KSeCOAr in acetone. The novel binuclear complexes, [Cp1IrCl(μ-SeCOAr)(κ²-SeCOC₆H₃R–)IrCp1] (2) (R = H or Me-4) with ortho-metallation at one of the iridium centres have been isolated following the use of excess AgPF₆. The single crystal structure of [Cp1IrCl(μ-SeCOC₆H₅)(κ²-SeCOC₆H₄–)IrCp1] (2a) exhibits two phenylcarboselenolate moieties situated in syn fashion with respect to the “Ir₂Se₂” plane, one of which leans towards the metal centre in order to undergo ortho-metallation after iridium–chlorine bond dissociation.     

Unexpected fragmentation of the Fe3(CO)9(μ3-Se)(μ3-AsCH3) cluster core in the reaction with CpCo(CO)2: synthesis and structure of Fe3(CO)6(μ3-Se)(μ-AsCH3{CpFe(CO)2})2(μ-CO)

The [Fe₃(CO)₆(μ₃-Se)(μ-AsCH₃{CpFe(CO)₂})₂(μ-CO)] (Cp=η⁵-C₅H₅) cluster has been obtained by the reaction of [Fe₃(CO)₉(μ₃-Se)(μ₃-AsCH₃)] with [CpCo(CO)₂]. Its crystal and molecular structures have been determined by X-ray analysis.     

Synthesis,structure and magnetic properties of a trinuclear cyano-bridged complex [Cu(bappz)(μ-NC)Ni(CN)2(μ-CN)Cu(bappz)](ClO4)2 {bappz=1,4-bis(3-aminopropyl)piperazine}

The bimetallic trinuclear complex [Cu(bappz)(μ-NC)Ni(CN)₂(μ-CN)Cu(bappz)](ClO₄)₂ (bappz=1,4-bis(3-aminopropyl)piperazine) has been prepared from the reaction of [Cu(bappz)](ClO₄)₂ and K₂[Ni(CN)₄] in water and its crystal and molecular structure has been determined. The structure consists of a trinuclear [Cu(bappz)(μ-NC)Ni(CN)₂(μ-CN)Cu(bappz)]²⁺ cation and two perchlorate anions. The bridging [Ni(CN)₄]²⁻ anion is coordinated by two [Cu(bappz)]²⁺ cations through two cyano groups, providing a novel trinuclear structure with the Cu–(NC)–Ni–(CN)–Cu linkage. The nickel(II) ion is four-coordinated by carbon atoms from four cyano groups (two of them, in trans position, form a bridge) in a square planar arrangement, whereas both the copper(II) ions are five-coordinated by four bappz nitrogens and one cyanide nitrogen in a distorted square–pyramidal geometry. The temperature dependence of magnetic susceptibility was measured for this compound over the range of 2–300 K. The magnetic investigation showed the presence of a very weak antiferromagnetic interaction (superexchange interaction parameter J=−0.54 cm⁻¹) between the copper atoms through the diamagnetic [Ni(CN)₄]²⁻ ion.     

Synthesis,structure, and substitution reactivity of a new bi-oxo capped molybdenum cluster: [Mo3(μ3-O)2(μ-O2CCH2Cl)6(H2O)2(OH)]+

A new bi-oxo capped molybdenum carboxylate, [Mo₃(μ₃-O)₂(μ-O₂CCH₂Cl)₆(H₂O)₂(OH)]⁺, was synthesized by refluxing [Mo₃(μ₃-O)₂(μ-O₂CCH₃)₆(H₂O)₃]^2 + in chloroacetic acid for 20 h (T = 110 °C). Using ion-exchange chromatography (0.5 M NaClO₄ eluant), the trinuclear molybdenum ion was isolated and allowed to crystallize slowly (T = 4 °C) as the perchlorate salt (yield 23%). Upon dissolution of the compound in methanol-d₄, substitution of the terminal ligands for solvent occurs readily in which the observed exchange rate constant is k_obs^298K = 5.3 × 10^− 5 (± 0.3) s^− 1 and activation parameters equal to ΔH³ = 130 (± 10) kJ mol^− 1 and ΔS³ = 111 (± 33) J mol^− 1 K^− 1. From the kinetic data, we find that ligand substitution follows a dissociative pathway and that rates of substitution are faster than expected when compared to the molybdenum acetate analog. Herein, we report the synthesis, crystallographic study, and substitution reactivity of a new molybdenum bi-oxo capped cluster with bridging chloroacetate ligands.     

Synthesis,supramolecular structure,and energetic properties of the first metal–organic nitrotetrazolate, [Me3Sn(μ-OH)SnMe3(μ-OH)SnMe3(H2O)][NT] (NT = 5-nitrotetrazolate)

The first metal–organic 5-nitrotetrazolate, [Me₃Sn(μ-OH)SnMe₃(μ-OH)SnMe₃(H₂O)][NT] (2), has been prepared by a simple metathetical reaction between Me₃SnCl and sodium 5-nitrotetrazolate dihydrate (= NaNT, 1). A single-crystal X-ray diffraction study revealed the presence of the trinuclear [Me₃Sn(μ-OH)SnMe₃(μ-OH)SnMe₃(H₂O)]⁺ cation to which the 5-nitrotetrazolate anion is coordinated via a ring-N atom. The NT anion is further engaged in four different OH⋯N and OH⋯N hydrogen bonds involving the remaining three ring-nitrogen atoms and one oxygen of the nitro group, leading to an extensive supramolecular hydrogen-bonded network in the solid state. Despite its very low N content of only 10.65%, compound 2 is highly impact-sensitive (< 2.5 J) and can be classified as a primary explosive.     

Crystal structure and catalytic studies of heterodinuclear complex [CuZn(μ-OAc)(μ-OH)(μ-OH2)(bpy)2](ClO4)2

The heterodinuclear copper–zinc complex [CuZn(μ-OAc)(μ-OH)(μ-OH₂)(bpy)₂](ClO₄)₂ has been synthesized from solid state reaction and its crystal structure was established. The heterobimetallic complex is quite efficient catalyst for hydrogen peroxide mediated oxidation of alcohols into corresponding carbonyl compounds.     

Synthesis,crystal structure and magnetic properties of one-dimensional cyano-bridged bimetallic complex of [Mn(Me2-bipy)2]3[W(CN)8]2·9H2O

An octacyanotungstate(V)-manganese(II) bimetallic assembly [Mn(Me₂-bipy)₂]₃[W(CN)₈]₂·9H₂O (1) (Me₂-bipy = 4,4′-dimethyl-2,2′-bipyridine) was synthesized in methanol and characterized by X-ray crystallography. X-ray analysis shows that complex 1 is a neutral, one-dimensional (1D) infinite chain polymer. Magnetic data analysis demonstrates a long-range magnetic interaction and two different antiferromagnetic coupling constants obtained by fitting between Mn and W ions in 1.     

Synthesis,characterization and crystal structure of one Mn(II) complex with 4,4′-bisimidazolylbiphenyl and 4,4′-sulfonyldibenzoic acid

One new title compound [Mn₃(BIBP)(sdb)(NO₂⁻)₂(H₂O)₂]_n·2DMF (1) (BIBP = 4,4′-bisimidazolylbiphenyl, sdb = 4,4′-sulfonyldibenzoic acid) has been synthesized under hydrothermal condition. The title compound was characterized by IR spectra, thermal analysis, single crystal and powder X-ray diffraction. Magnetic susceptibility measurements indicate that compound 1 exhibits antiferromagnetic coupling interaction.     

Tricarbonyl rhenium complex of 2,2′-bis(4,5-dimethylimidazole) — Synthesis,spectroscopic characterization,X-ray structure and DFT calculations

The paper presents a combined experimental and computational study of the tricarbonyl rhenium(I) complex incorporating 2,2′-bis(4,5-dimethylimidazole) (tmbiimH₂). The complex has been studied by IR, UV–Vis spectroscopy and X-ray crystallography. The electronic structure of [Re(CO)₃(tmbiimH₂)Cl] has been calculated with the density functional theory (DFT) method, and the electronic spectrum of the complex was investigated at the TDDFT level employing B3LYP functional in combination with LANL2DZ.     

New dinuclear Pd(II) complex with pyrazolate bridges. Synthesis and crystal structure of [Pd(μ-pz)(pzH)2]2(BF4)2 (pzH=pyrazole)

Dinuclear pyrazolate-bridged Pd(II) complex [Pd(μ-pz)(pzH)₂]₂(BF₄)₂ has been prepared by treatment of pyrazole (pzH), sodium ethoxide, and [Pd(CH₃CN)₄](BF₄)₂. The new complex has been characterised by elemental analyses, IR, ¹H NMR, ¹³C{¹H} NMR, and single crystal X-ray diffraction methods. This structure shows two palladium atoms bridged by two pyrazolate ligands. The square-planar geometry of each Pd atom is completed by two pyrazole ligands. The six-membered dipalladacycle formed by the two Pd atoms and the two bridging pyrazolate ligands adopt a distorted boat-like conformation. This compound is the first example of a dinuclear Pd(II)–pyrazolate homoleptic complex.     

Synthesis,crystal structure and second harmonic generation of (DMAPM+)[Cd(DMAP)I3]−

A new inorganic–organic hybrid, (DMAPM⁺)[Cd(DMAP)I₃]⁻, (DMAPM⁺I⁻=4-N,N-dimethylamino-1-methyl-pyridinium iodide, DMAP = 4-N,N-dimethylamino- pyridine) 1, has been prepared, showing a moderate second harmonic generation (SHG) of about three times as strong as that of potassium dihydrogen phosphate (KDP).