European Journal of Inorganic Chemistry

The control of the diastereoselectivity (cis/trans) achieved by transition-metal complexes employed as catalysts in the olefin cyclopropanation reaction with ethyl diazoacetate is reviewed.

The new ionic liquids 3-cyanomethyl-1-methylimidazolium tetrachlorocadmate and 3-(4-cyanobutyl)-1-methylimidazolium tetrachlorocadmate can be obtained by reacting the respective alkylimidazolium chlorides with cadmium chloride in 2:1 molar ratios. Once molten, both compounds show little tendency to solidify at room temperature and below.

Phosphane ligands are observed to affect the addition of E–E bonds to alkynes: an excess of phosphane ligand decreases the performance of the catalytic reaction in some cases, whereas in others the catalyst is totally inactive in the absence of an excess of ligand. The metal particle leaching promoted by the phosphane ligand is used to create a new catalytic reaction.

A two-step complexation procedure using cobalt(III) to prepare building blocks, then silver(I) to connect them through the “spare” nitrogen atoms “outthe back” of the building block complexes, was successful generating {[Co^III(L^1E)₂]₂[Ag^I(H₂O)]}(BF₄)(NO₃)₂ (structure shown).

Four mononuclear nickel(II) complexes contain a surprising and strong anion–π-anion “sandwiching” arrangement that seems to contradict the current simple electrostatic description of anion–π interactions.

The Zn^II compounds [ZnCl₂(PTA)₂] (PTA = 1,3,5-triaza-7-phosphaadamantane) and [PTA–Me]₂[ZnI₂X₂] (X = Cl, X = I; PTA–Me = N-methyl-1,3,5-triaza-7-phosphaadamantane) have been prepared by treatingZnCl₂ with PTA and [PTA–Me]I, respectively, in methanol at room temperature. [ZnCl₂(PTA)₂] represents the first example of a Zn complex bearing PTA or any derived ligand with a cage-like PTA core.

The solid-state structure of [{2-(Me₂NCH₂)C₆H₄}₂Sb]₂E [E = O, S] revealed square-pyramidal (C,N)₂SbE cores, whereas the NMR spectroscopic data are consistent with configuration stability of the Sb atom. By contrast, in [{2-(Me₂NCH₂)C₆H₄}₂SbOH][W(CO)₅] the Sb center has a trigonal-bipyramidal environment, and one of the N atoms is involved in intramolecular hydrogen bonding.

Zeolite beta was successfully desilicated using tetramethylammonium hydroxide. It is shown that calcination of the desilicated material directly produces the mesoporous acidic form of the zeolite. A protocol integrating the post-synthesis treatments desilication and ion-exchange is thus presented.

Fe³⁺ complexes of pyridine-containing copolymers show effective oxidative double-stranded DNA cleavage and selective and efficient catalysis toward phosphodiester hydrolysis at pH 6–8. One complex exhibited significant first-order catalytic proficiency toward the hydrolysis of bis(p-nitrophenyl) phosphate at pH 5.3 and at 25 °C, representing a functional model of an acid phosphoesterase.

A general and straightforward synthesis of alkali metal tetraselenohypodiphosphonates (RP)₂Se₄M₂ (R = alkyl, aryl; M = Li, Na) is presented. Their ³¹P and ⁷⁷Se NMR spectra are discussed. The crystal structures of two of the salts reveal different coordination modes of the (RP)₂Se₄^2– anion to the alkali metal cations.

Crystalline anatase microspheres of hierarchical structures are obtained directly by homogeneous precipitation under mild conditions (83–100 °C, 30 min) using ammonium fluorotitanate as the titanium source and urea as the precipitant.

A real scorpionate: Scorpions normally do not sting with their tail until they have their prey firmly in their grasp. The new family of facially capping ligands reported, the β-triketimines, fits the arachnomorphic analogy better than previous “scorpionate” ligands, in that most examples exist in a pro-bidentate form, which converts to an N,N′,N″-κ₃-tridentate ligand only when presented with Cr-goup metal “prey”. Once in this complexed form, C₃-symmetric examples self-organise to form a microporous network.

Coupling of lithium 2-lithiocresolate with ClPPh₂ and subsequently with ClSiMe₃/MeOH, ClP(O)Ph₂, or RC(O)Cl (R = Me, tBu, Ph, 4-MeOC₆H₄) provided 2-phosphanylcresol 1, its phosphinic acid ester 2,and carboxylic esters 3a–d, in part structurally characterized by X-ray diffraction. In contrast to ethers of 1, the esters give highly active nickel catalysts for polymerization of ethylene.

A series of heterobimetallic (monophthalocyaninato)lanthanide complexes of Yb and Er supported by a tripodal cobalt-based ligand have been synthesized and structurally characterized. Photophysical studies show that these complexes show distinct near-infrared emissions, with the singlet oxygen phosphorescence responsible for the Yb³⁺ case and the lanthanide ion emission for the Er³⁺ congener.

Chiral bis(N-heterocyclic carbene) complexes of rhodium(I) and iridium(I) are prepared by a six-step synthesis starting from L-valinol. This route makes it possible to modify the ligand at severalpositions. The exo and endo complex isomers are characterised by ¹H NMR spectroscopy and single-crystal X-ray diffraction.

Molecular receptors containing a Ru^II/Re^I bpy/phen moiety as fluorophore and a crown ether as ionophore have been synthesised and their luminescence, electrochemical and cation-binding propertieswith a large number of metal ions investigated. Luminescence and ¹H NMR spectroscopic studies suggest a strong complexation of the ionophores with certain metal ions.

Diiron complexes bearing bridging functionalized C₃ organic frameworks can be transformed into chelating N,S ligands. Several modifications and functionalizations of the bridging C₃ framework are possible, thus making these “organometallic ligands” very versatile.