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Novel aluminium and chromium salphen complexes are prepared (not shown) and applied to the synthesis of cyclic carbonates from a range of epoxides and carbon dioxide.

Four new quaternary chalcogenides, Ba4AgGaS6 (1), Ba4AgGaSe6 (2), Ba4CuInS6 (3), and Ba4AgInS6 (4), were synthesized by solid-state reactions and their structures were characterized through single-crystal X-ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6](8-) 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner-sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1, 2, and 3, but they occupy independent crystallographic sites in 4. As a result, compounds 1-3 belong to the known Ba2CoS3 (Pnma No. 62) or Ba2 MnS3 (Pnma No. 62) class, whereas 4 crystallizes in its own structural type within the monoclinic P2₁/c (No. 14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well.

The use of sustainable metal-based catalysts for the synthesis of five-membered ring containing cyclic carbonates from epoxides and carbon dioxide is critically reviewed. Coverage is restricted to catalysis by the abundant metals: sodium, potassium, aluminium, calcium, titanium and iron and the relative merits and limitations of each catalyst system are compared.

Two new europium-containing Zintl phases, Eu3Si2As4 and Eu3Ge2As4, were discovered from metal flux reactions and their structures were identified by using single-crystal X-ray diffraction. Both compounds crystallize in the monoclinic space group P21/c and are isotypic to Sr3Ge2As4. Magnetic property studies were performed and the results proved the long-range antiferromagnetic behavior for Eu3Ge2As4 but with a positive Weiss constant, which suggested the coexistence of both ferromagnetic and antiferromagnetic order of Eu 4f electrons in the structure. Density functional calculations were incorporated to understand the related magnetic properties as well.

Two homochiral metal–organic, sextuply-stranded, lantern-like complexes, Ce-L-Pro1 and Ce-D-Pro1, were synthesized via self-assembly by incorporating a L or D-pyrrolidine moiety within the respective ligands. The Ce-Pro1 complexes are comprised of chiral pyrrolidine-containing ligands and have lantern-like cavities. They function as asymmetric catalysts that promote cyanosilylation reactions with good conversions and enantioselectivity.

The new title compound (dien: diethylenetriamine) is solvothermally synthesized from a mixture of Ge powder, Mn(OAc)2, and sulfur powder in aqueous dien solution (autoclave, 130 °C, 7 d, 7% yield).

The title compound is prepared from the elements (Nb tube, 850 °C, 5 d) and characterized by single crystal XRD.

The new compounds Sc2Nb4-xSn5 (x = 0.37, 0.52), YNb6Sn6, and ErNb6Sn5 are synthesized from mixtures of the elements (1000—1050 °C for 8 d, annealing at 770—850 °C for 8—10 d, 30% yield for ErNb6Sn5).

Crystalline chalcogenides are prepared in ionic liquids containing N2H4·H2O leading to a well-controlled crystallization process.

A homochiral Co(II)-organic, triangular, supramolecular catalyst incorporating L-proline moieties presented here features a helical cavity and efficiently promotes aldol reactions in a size-, stereo- and enantioselective manner.

K2Mg4.72Sn3 and K3Mg18Tt11 (Tt: Sn, Pb) are synthesized from mixtures of the elements (800 °C for 2—3 d followed by annealing at 500—520 °C for 6—7 d) and characterized by single crystal XRD.

Tm3MnSn4.84, Tm3MnSn4.71, Lu3MnSn4.95, and Lu3MnSn4.79 are prepared from the corresponding elements (Ta tubes, 1050 °C, 7 d followed by annealing at 650 °C for 15 d).

The title compounds have been obtained by solid state reactions of the corresponding pure elements at high temperature, and structurally characterized by single-crystal X-ray diffraction studies. Yb 5 Ni 4 Sn 10 adopts the Sc 5 Co 4 Si 10 structure type and crystallizes in the tetragonal space group P 4 /mbm (No. 127) with cell parameters of a =13.785(4) A, c =4.492 (2) A, V=853.7(5) A 3 , and Z =2. Yb 7 Ni 4 Sn 13 is isostructural with Yb 7 Co 4 InGe 12 and crystallizes in the tetragonal space group P 4 /m (No. 83) with cell parameters of a =11.1429(6) A, c =4.5318(4) A, V=562.69(7) A 3 , and Z =1. Both structures feature three-dimensional (3D) frameworks based on three different types of one-dimensional (1D) channels, which are occupied by the Yb atoms. Electronic structure calculations based on density functional theory (DFT) indicate that both compounds are metallic. These results are in agreement with those from temperature-dependent resistivity and magnetic susceptibility measurements.

Three new ternary potassium(I) zinc(II) or cadmium(II) tellurides, namely, K 2 Cd 2 Te 3 , K 6 CdTe 4 and K 2 ZnTe 2 , were synthesized by solid-state reactions of the mixture of pure elements of K, Cd (or Zn) and Te in Nb tubes at high temperature. K 2 Cd 2 Te 3 belongs to a new structure type and its structure contains a novel two-dimensional [Cd 2 Te 3 ] 2− layers perpendicular to the b -axis. K(5) cation is located at the center of five member rings of the 2D [Cd 2 Te 3 ] 2− layer, whereas other K + cations occupy the interlayer space. K 6 CdTe 4 with a K 6 HgS 4 type structure features a “zero-dimensional” structure composed of isolated CdTe 4 tetrahedra separated by the K + ions. K 2 ZnTe 2 in the K 2 ZnO 2 structural type displays 1D [ZnTe 2 ] 2− anionic chains of edge sharing [ZnTe 4 ] tetrahedra separated by the potassium(I) ions. K 2 Cd 2 Te 3 , K 6 CdTe 4 and K 2 ZnTe 2 revealed a band gap of 1.93, 2.51 and 3.0 eV, respectively.

The title three compounds have been synthesized by solid state reactions at high temperatures, with excess indium as flux, and structurally characterized by single-crystal X-ray diffraction studies. Eu3Co2In15 forms a new structure type and crystallizes in the tetragonal space group P4/mbm (No. 127), whereas KM2In9 (M = Co, Ni) in the BaFe2Al9 type crystallizes in the hexagonal space group P6/mmm (No. 191). Their structures all feature a three-dimensional anionic framework based on 1D [MIn6] single cluster chains composed of face-sharing [MIn9] clusters. In Eu3Co2In15, two adjacent [CoIn6] single cluster chains form a [Co2In11] double cluster chain via corner-sharing In atoms as well as In−In bonds; the latter chains are further interconnected by additional indium atoms via In−In bonds into a complicated 3D framework, forming two types of tunnels along the c-axis, which are filled by the europium atoms. In KM2In9, the [MIn6] single cluster chains are directly interconnected via corner sharing and exo In−I...

Two new ternary ytterbium transition metal stannides, namely, Yb3CoSn6 and Yb4Mn2Sn5, have been obtained by solid-state reactions of the corresponding pure elements in welded tantalum tubes at high temperature. Their crystal structures have been established by single-crystal X-ray diffraction studies. Yb3CoSn6 crystallizes in the orthorhombic space group Cmcm (no. 63) with cell parameters of a=4.662(2), b=15.964(6), c=13.140(5) A, V=978.0(6) A3, and Z=4. Its structure features a three-dimensional (3D) open-framework composed of unusual [CoSn3] layers interconnected by zigzag Sn chains, forming large tunnels along the c-axis which are occupied by the ytterbium cations. Yb4Mn2Sn5 is monoclinic space group C2/m (no. 12) with cell parameters of a=16.937(2), b=4.5949(3), c=7.6489(7) A, β=106.176(4)°, V=571.70(8) A3, and Z=2. It belongs to the Mg5Si6 structure type and its anionic substructure is composed of parallel [Mn2Sn2] ladders interconnected by unusual zigzag [Sn3] chains, forming large tunnels along the c-axis, which are filled by the ytterbium cations. Band structure calculations based on density function theory methods were also made for both compounds.