Ning-Hai Hu

Self-immobilized catalysts for ethylene polymerization: neutral, single-component salicylaldiminato phenyl nickel(ii) complexes bearing allyl substituentsElectronic supplementary information (ESI) available. Synthesis and spectroscopic data for 5, spectroscopic data for 1–4. See http://www.rsc.org/suppdata/cc/b1/b110258n/

A new family of self-immobilized ethylene polymerization catalysts, derived from neutral, single-component salicylaldiminato phenyl nickel complexes, is described.

Co-existing intermolecular halogen bonding, aryl packing and hydrogen bonding in driving the self-assembly process of Keggin polyoxometalates

A new series of supramolecular architectures based on Keggin polyoxometalates (POMs): (Hbpy)3[PMo12O40]·2.2H2O (1), (H3/4bppy)4H2[PMo12O40]·3H2O (2), (Hbppy)4H2[SiW12O40]·3H2O (3) and (Hppy)4H2[SiMo12O40] (4) (bpy = 4-(5-chloropyridin-2-yl)pyridine, ppy = 4-(5-phenylpyridin-2-yl)pyridine and bppy = 4-(5-(4-bromophenyl)pyridin-2-yl)pyridine), has been prepared and characterized. In compound 1, no direct interaction occurs among POM anion clusters, and the anions together with organic molecule bpys construct the supramolecular frameworks to accommodate guest water molecules. In compounds 2 and 3, Keggin anions form one-dimensional pillar-like inorganic chains as a ‘guest’ to occupy the supramolecular spaces formed by compact organic array, while POMs form two-dimensional layers and alternative array with organic layers in compound 4. Noncovalent interactions of hydrogen bonding, aryl packing and halogen bonding coexist in compounds 1–3. The C–X⋯O (X = Cl or Br) synthon is introduced for the first time to drive self-assembly process of POMs. The crystal structure analyses reveal that the substituted groups of organic bipyridine have a major influence on the packing arrangement of crystals. Additionally, the different cation ∶ anion ratios (3 in 1, and 4 in the other compounds) may also in part affect the packing modes of the organic and inorganic moieties.

Copper(II) metal–organic networks derived from bis(pyridylformyl)piperazine ligands and aromatic polycarboxylates: 2D layered structures and a novel 3,5-connected binodal 3D topology

Three novel coordination polymers [Cu2(3-bpfp)(BDC)2(H2O)2]·4H2O (1), [Cu(3-bpfp)(HBTC)]·0.5H2O (2) and [Cu(4-bpfp)0.5(HBTC)(H2O)] (3) have been hydrothermally synthesized by self-assembly of aromatic polycarboxylate ligands H2BDC (H2BDC = 1,3-benzenedicarboxylate acid) or H3BTC (H3BTC = 1,3,5-benzenetricarboxylate acid), bridging ligands 3-bpfp/or 4-bpfp [3-bpfp = bis(3-pyridylformyl)piperazine, 4-bpfp = bis(4-pyridylformyl)piperazine], and copper chloride. X-Ray diffraction analysis reveals that each CuII ion is connected by BDC/or HBTC and 3-bpfp/or 4-bpfp ligands to form two dimensional (2D) layer structures in compounds 1 and 3. Ligands 3-bpfp and 4-bpfp both display μ4-bridging coordination mode in 1 and 3 (via ligation of pyridyl nitrogen and carbonyl oxygen atoms). In compound 2, each CuII ion is connected by HBTC to construct 2D polymeric layers, which are further linked into a novel 3,5-connected 3D coordination polymeric framework with (4·62)(4·66·83) topology by 3-bpfp ligand in μ2-bridging mode (via ligation of pyridyl nitrogen atoms). Compound 2 is the first 3D example of coordination polymer constructed from 3-bpfp and aromatic polycarboxylate ligands. Moreover, the electrochemical properties of the three copper compounds bulk modified carbon paste electrodes have been studied.

Aliphatic amino acid-metal ion-aromatic amine ternary complexes. Crystal structures of aqua(L-leucinato)(1,10-phenanthroline)copper(II) nitrate and aqua(DL-leucinato)(1,10-phenanthroline)copper(II) nitrate

Abstract The crystal structures of the two aliphatic amino acid-metal ion-aromatic diamine ternary complexes, [Cu( L -Leu)( o -phen)(H 2 O)]NO 3 (1) and [Cu( DL -Leu)( o -phen) (H 2 O)]NO 3 (2) (Leu=leucinato and o -phen=1,10-phenanthroline), have been determined by X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 with a =12.362(2), b =11.593(2), c =7.311(2) A, α=107.82(2), β=76.05(2), γ=93.62(2)°, Z =2, D calc =1.557 g cm −3 , and R =0.045 for 3184 unique observed reflections. Complex 2 crystallizes in triclinic space group P 1 with a =12.368(4), b =11.608(4), c =7.280(3) A, α=107.16(3), β=75.98(3), γ=93.54(3)°, Z =2, D calc =1.556 g cm −3 , and R =0.052 for 2579 unique observed reflections. The L -Leu complex (1) involves two crystallographically independent molecules, which are related by a pseudo center of symmetry except for the C β atoms. Both the 1 and 2 structures are essentially identical, including the crystal packing mode, except for the existence of an exact crystallographic center of symmetry in 2. In 2 the C β atom of Leu is disordered at two positions corresponding to D - and L -configurations, respectively. In each complex, the copper atom is coordinated in a distorted squarepyramidal geometry by the bidentate Leu and o -phen ligands at the equatorial sites and water at an axial position. The isopropyl side chain of each Leu extends away from the aromatic ring system of o -phen, thus there is no intramolecular ligand-ligand interaction between them, in contrast to a ring-aliphatic hydrophobic interaction in solution for this ternary system. Factors affecting the formation of a folded structure having such an interligand interaction are considered from the structural viewpoint.

7. Solid State Structures of Lead Complexes with Relevance for Biological Systems

Structural information on the interaction between lead ion and its targeting biological substances is important not only for enriching coordination chemistry of lead but for successfully treating lead poisoning that is a present-day problem. This chapter provides structural data, mainly metal binding sites/modes, observed in crystal structures of lead complexes with biorelevant molecules, obtained from the Cambridge Structural Database (the CSD version 5.36 updated to May 2015) and the Protein Data Bank (PDB updated to February 2016). Ligands include (i) amino acids and small peptides, (ii) proteins, (iii) nucleic acid constituents, (iv) nucleic acids, (v) simple saccharides, and (vi) other biorelevant molecules involving lead-detoxification agents. For representative complexes of these ligands, some details on the environment of the metal coordination and structural characteristics are described.

Synthesis and characterization of a new double-cubane Mo-Fe–S cluster compound, [NEt4]3[Mo2Fe6S8(µ-OMe)3(SPh)3Cl3]

The new double-cubane cluster compound [NEt4]3[Mo2Fe6S8(µ-OMe)3(SPh)3Cl3] is synthesized from (NH4)2MoS4, FeCl3, Fe powder, S powder, NaSPh and NEt4Br in MeOH–DMF, its crystal structure is determined by X-ray crystallography, and results of XPS indicate a valence state of +4 for Mo.