Optimized Electrode/Electrolyte Interface of MWCNT/SnO2 Composite through Gas-Solid Fluorination.

The benefit of enriching solid-electrolyte interface with fluorine atoms through the use of fluorinated additives into the electrolyte composition has recently gained popularity for anode materials used in secondary lithium-ion batteries. Another strategy is to provide these fluorine atoms via surface fluorination of the electrode material, particularly for multiwalled carbon nanotube (MWCNT)/SnO2-based composites where fluorination must act selectively on SnO2. Our study presents two methods of surface fluorination applied on MWCNT/SnO2, one using F2(g) and the other XeF2(s). These fluorinating agents are known for their different particle penetration depths. An ultrathin and very dense fluorinated layer achieved by the action of F2(g) allows to form a very stable interface leading to gravimetric capacities of 789 mA h g-1 after 50 cycles. A thin and porous fluorinated layer made by the action of XeF2(s) favors the formation of a new Sn-based fluorinated phase, never reported in the literature, which also stabilizes capacities over 50 cycles. In any case, the value of adding fluorine atoms to the surface of the electrode material to improve cycle stability is demonstrated.

Three zinc(II) and cadmium(II) complexes containing 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole and polynitrile ligands: synthesis, molecular and supramolecular structures, and photoluminescence properties.

Three photoluminescent complexes containing either ZnII or CdII have been synthesized and their structures determined. Bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N1,N5]bis(dicyanamido-κN1)zinc(II), [Zn(C12H10N6)2(C2N3)2], (I), bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N1,N5]bis(dicyanamido-κN1)cadmium(II), [Cd(C12H10N6)2(C2N3)2], (II), and bis[4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole-κ2N1,N5]bis(tricyanomethanido-κN1)cadmium(II), [Cd(C12H10N6)2(C4N3)2], (III), all crystallize in the space group P-1, with the metal centres lying on centres of inversion, but neither analogues (I) and (II) nor CdII complexes (II) and (III) are isomorphous. A combination of N-H...N and C-H...N hydrogen bonds and π-π stacking interactions generates three-dimensional framework structures in (I) and (II), and a sheet structure in (III). The photoluminescence spectra of (I)-(III) indicate that the energies of the π-π* transitions in the coordinated triazole ligand are modified by minor changes of the ligand geometry associated with coordination to the metal centres.

Macrocyclic arylopeptoids--a novel type of cyclic N-alkylated aromatic oligoamides forming nanotubular assemblies.

The head-to-tail conversion of linear arylopeptoids (oligomeric N-substituted aminomethyl benzamides) into the derived novel macrocycles has enabled the first X-ray structures of arylopeptoid constructs and the identification of well-defined architectures in solution.

Poly[[chlorido(1,10-phenanthroline-κ2N,N')copper(II)]-µ3-1,1,3,3-tetracyano-2-ethoxypropenido-κ3N:N':N'']: coordination polymer sheets linked into bilayers by hydrogen bonds.

In the title compound, [Cu(C9H5N4O)Cl(C12H8N2)]n or [Cu(tcnoet)Cl(phen)]n, where phen is 1,10-phenanthroline and tcnoet is 1,1,3,3-tetracyano-2-ethoxypropenide, the axially elongated (4 + 2) coordination polyhedron around the Cu(II) centre contains N atoms from three different tcnoet ligands. The resulting coordination polymer takes the form of sheets which are linked in pairs by a single C-H...N hydrogen bond to form bilayers. The bond lengths provide evidence for significant bond fixation in the phen ligand and extensive electronic delocalization in the tcnoet ligand, where the two -C(CN)2 units are rotated, in conrotatory fashion, out of the plane of the central C3O fragment.

(Adipato-κ(2) O,O')di-aqua-[bis-(pyridin-2-yl-κN)amine]-cobalt(II) trihydrate.

In the monomeric title complex, [Co(C6H8O4)(C10H9N3)(H2O)2]·3H2O, the distorted octa-hedral CoN2O4 coordination environment comprises two N-atom donors from the bidentate di-pyridyldi-amine ligand, two O-atom donors from one of the carboxyl-ate groups of the bidentate chelating adipate ligand and two water mol-ecules. In addition, there are three solvent water mol-ecules which are involved in both intra- and inter-unit O-H⋯O hydrogen-bonding inter-actions, which together with an amine-water N-H⋯O hydrogen bond produce a three-dimensional framework.

Tris(1,10-phenanthroline-κ(2) N,N')iron(II) bis-(1,1,3,3-tetra-cyano-2-eth-oxy-propenide) hemihydrate.

In the title hydrated mol-ecular salt, [Fe(C12H8N2)3](C9H5N4O)2·0.5H2O, the water mol-ecule site is half-occupied. The Fe-N bond lengths within the octa-hedral tris-chelate [Fe(phen)3](2+) ion (phen is 1,10-phenantroline) are indicative of a low-spin d(6) electronic configuration for the metal ion. The C-N, C-C and C-O bond lengths in the polynitrile anions indicate extensive electronic delocalization. In the crystal, the components are linked through O-H⋯N hydrogen bonds, forming [100] chains, as well as through Coulombic inter-actions.

3-Amino-pyridinium trans-diaqua-dioxalato-chromate(III).

In the structure of the title compound, (C5H7N2)[Cr(C2O4)2(H2O)2], two crystallographically independent formula units are present. Both chromium atoms are six-coordinated in a distorted octa-hedral geometry by two chelating equatorial oxalato ligands and two axial water mol-ecules. The [Cr(C2O4)2(H2O)2]⁻ anions and C5H7N2 ⁺ cations are linked through a complex three-dimensional hydrogen-bonding network consisting of N-H⋯O and O-H⋯O inter-actions.

Ca(5)Zr(3)F(22).

Single crystals of Ca(5)Zr(3)F(22), penta-calcium trizirconium docosafluoride, were obtained unexpectedly by solid-state reaction between CaF(2) and ZrF(4) in the presence of AgF. The structure of the title compound is isotypic with that of Sr(5)Zr(3)F(22) and can be described as being composed of layers with composition [Zr(3)F(20)](8-) made up from two different [ZrF(8)](4-) square anti-prisms (one with site symmetry 2) by corner-sharing. The layers extending parallel to the (001) plane are further linked by Ca(2+) cations, forming a three-dimensional network. Amongst the four crystallographically different Ca(2+) ions, three are located on twofold rotation axes. The Ca(2+) ions exhibit coordination numbers ranging from 8 to 12, depending on the cut off, with very distorted fluorine environments. Two of the Ca(2+) ions occupy inter-stices between the layers whereas the other two are located in void spaces of the [Zr(3)F(20)](8-) layer and alternate with the two Zr atoms along [010]. The crystal under investigation was an inversion twin.

Access to functionalised silver(I) and gold(I) N-heterocyclic carbenes by [2 + 3] dipolar cycloadditions.

A new strategy was developed for the modification of silver(I) and gold(I) N-heterocyclic carbenes. Azido groups were grafted and used either by copper-catalysed azide-alkyne cycloaddition before metallation or by thermal and "strain-promoted" 1,3-dipolar cycloaddition after metallation to functionalise the metal-NHCs.

Use of copper(I) catalyzed azide alkyne cycloaddition (CuAAC) for the preparation of conjugated pyrrolo[2,3-a]carbazole Pim kinase inhibitors.

We have previously demonstrated that pyrrolo[2,3-a]carbazole-3-carbaldehydes are potent Pim kinase inhibitors with in vitro antiproliferative activities. In the present study, we report the synthesis of new pyrrolocarbazoles substituted at the N-10 position. When their ability to inhibit Pim kinase activities were evaluated in in vitro assays, we observed that this nitrogen atom can be substituted without loss of Pim-1 and Pim-3 inhibitory potencies. Moreover, when we added a fluorescent dansyl group (compound 13), we were able to show that 13 penetrates the plasma membrane and enters the cytoplasm.

A platinum Chugaev carbene complex as a potent anticancer agent.

A platinum Chugaev complex was synthesised and fully characterized by multinuclear NMR spectroscopy and X-ray crystallography. This cis bis acyclic diamino carbene complex acts as a cytotoxic compound and behaves as a cisplatin equivalent by interacting with supercoiled DNA and thiols. Stability of the ligand is also discussed.

Pseudotetragonal structure of Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50): the first mixed valence cerium fluoride.

The crystal structure of the new Li(5.5)Ce(12)F(50) compound has been fully characterized by single-crystal and synchrotron powder X-ray diffraction. An accurate pseudotetragonal structure was described in the monoclinic P2(1) space group with 68 independent crystallographic sites. The Li(5.5)Ce(12)F(50) composition belongs to the Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) solid solution. Its structure consists of an opened fluorine framework where a channel network allows the intercalation of relatively mobile lithium cations, inducing the formation of the mixed-valence cerium (the intercalation of Li(+) leads to the reduction of a part of Ce(4+) to Ce(3+)). One part of the lithium ions, necessary for the electroneutrality of the tetravalent equivalent cerium fluoride (Li(2)Ce(12)F(50) composition), is in a locked fluorine polyhedron. Only the supplementary x amount of lithium is able to be exchanged in Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50). The structure of Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) is a rearrangement, due to lithium intercalation, of the base CeF(4) structure. Bond valence calculation on Ce sites, Ce coordination polyhedra volumes, and a calculated Ce cationic radius give the indication of a partial long-range ordering of trivalent and tetravalent cerium cations in specific slabs of the structure. (7)Li NMR spectroscopy and XPS analyses have confirmed all of the structure details.

Aluminium cyclo-hexa-phosphate.

Single crystals of the title compound, Al(2)P(6)O(18), were obtained by solid-state reaction. The monoclinic structure is isotypic with its Cr(III), Ga(III) and Ru(III) analogues and is built up of six-membered phosphate ring anions, P(6)O(18) (6-), isolated from each other and further linked by isolated AlO(6) octa-hedra by sharing corners. Each AlO(6) octa-hedron is linked to four P(6)O(18) (6-) rings. More accurately, two rings are linked through bidentate diphosphate groups attached in the cis-positions to the AlO(6) octa-hedron. The other two rings are linked to the two remaining corners, also in cis-positions of the AlO(6) octa-hedron.

Bis(2,2'-bi-1H-imidazole)-copper(II) bis-(1,1,3,3-tetra-cyano-2-eth-oxy-propenide).

In the title compound, [Cu(C(6)H(6)N(4))(2)](C(9)H(5)N(4)O)(2), the Cu(2+) ion (site symmetry ) is coordinated by two N,N'-bidentate 2,2'-biimidazole (H(2)biim) ligands, generating a square-planar CuN(4) geometry. The dihedral angle between the aromatic rings in the ligand is 0.70 (9)°. In the polynitrile 1,1,3,3-tetra-cyano-2-eth-oxy-propenide (tcnoet) anion, the C-N, C-C and C-O bond lengths indicate extensive electronic delocalization. An alternative description for the metal-ion geometry is an extremely distorted CuN(6) octa-hedron, with two N-bonded tcnoet anions completing the coordination. In the crystal, the components are linked by N-H⋯N and C-H⋯N inter-actions.

α-Ba(2)P(2)O(7).

Single crystals of α-Ba(2)P(2)O(7), dibarium diphosphate, were obtained by solid-state reaction. The ortho-rhom-bic structure is isotypic with α-Sr(2)P(2)O(7) and is the second polymorph obtained for this composition. The structure is built from two different BaO(9) polyhedra (both with m symmetry), with Ba-O distances in the ranges 2.7585 (10)-3.0850 (6) and 2.5794 (13)-2.9313 (4) Å. These polyhedra are further linked by sharing corners along [010] and either edges or triangular faces perpendicularly to [010] to form the three-dimensional framework. This polyhedral linkage delimits large channels parallel to [010] where the P(2)O(7) diphosphate anions are located. These groups (symmetry m) are characterized by a P-O-P angle of 131.52 (9)° and an eclipsed conformation. They are connected to the BaO(9) polyhedra through edges and corners.

Dipotassium hexa-aqua-nickel(II) bis-[hexa-fluoridozirconate(IV)].

Single crystals of the title compound, K(2)[Ni(H(2)O)(6)][ZrF(6)](2), were grown by slow evaporation of a 40% aqueous HF solution in which a stoichiometric mixture of NiCl(2)·6H(2)O, ZrF(4) and KCl was dissolved. The monoclinic structure is isotypic with its K(2)Cu, K(2)Zn, Cs(2)Zn and Cs(2)Cu analogues. The structure is built up from isolated, slightly elongated octa-hedral [Ni(H(2)O)(6)](2+) complex cations (symmetry ) and dimeric [Zr(2)F(12)](4-) complex anions (symmetry ) that are also isolated from each other. The [Zr(2)F(12)](4-) anion results from the association of two distorted penta-gonal-bipyramidal [ZrF(7)] coordination polyhedra by sharing an equatorial edge passing through an inversion center of the unit cell. Both isolated [Ni(H(2)O)(6)](2+) and [Zr(2)F(12)](4-) complex ions are situated in planes parallel to (010). They are connected by the eight-coordinated K(+) ions into a three-dimensional structure. An intricate O-H⋯F hydrogen-bonding network consolidates the structure.

Improved copper(I)-NHC catalytic efficiency on huisgen reaction by addition of aromatic nitrogen donors.

A simple addition with a large impact: Addition of aromatic amines such as phenanthroline and 4-DMAP (4-dimethylaminopyridine) increases copper(I)-catalyzed azide alkyne cycloaddition (CuAAC) catalytic activity of [CuCl(SIMes)] at a large range of temperatures in such a way that efficient catalysis can safely take place in hydro-alcoholic solvents (see scheme).

An ortho-rhom-bic polymorph of the ultraphosphate YP(5)O(14).

Single crystals of yttrium penta-phosphate(V), YP(5)O(14), were obtained by solid-state reaction. The ortho-rhom-bic title compound belongs to the family of ultraphosphates and is the second polymorph of this composition. It is isotypic with its Ho and Er analogues. The structure contains two bridging Q(2)-type PO(4) tetra-hedra and one branching Q(3)-type PO(4) tetra-hedron, leading to infinite ultraphosphate ribbons running along the a axis. The coordination polyhedron around the Y(3+) cation may be described as distorted bicapped trigonal-prismatic. The YO(8) polyhedra are isolated from each other. They are linked by corner-sharing to the O atoms of six Q(2)-type and of two Q(3)-type PO(4) tetra-hedra into a three-dimensional framework.

Anti-KSbF6 structure of CaTbF6 and CdTbF6: a confirmation of the singular crystal chemistry of Tb4+ in fluorides.

The crystal structures of two new tetravalent terbium fluorides, CaTbF6 and CdTbF6, have been determined from X-ray and neutron powder diffraction data. The title compounds exhibit an anti-KSbF6 structure, the three-dimensional framework of which is built of [TbF6]2- chains of edge-sharing dodecahedra further linked, by sharing corners, to isolated [MF6]4- octahedra (M=Ca, Cd). The mechanism of the anionic sublattice rearrangement when going from KSbF6 to CaTbF6 is described and related to a simple cubic fluoride-ion packing. Comparison with the crystal structures of beta-BaTbF6 and other representatives of the M(II)M('IV)F6 family allows the singular crystal-chemical properties of some fluoroterbates to be emphasized.