Inorganic Chemistry Communications (v.6, #11)

Contents List (iii-iv).

Reaction of 2,6-bis(bis(2-pyridylmethyl)amino)methylpyridine (bpa-tpa) with Co(ClO4)2  ·6H2O has produced [Co(tpaCO2)Cl](ClO4), the first structurally characterised cobalt(III) complex of a ligand based on the tris(2-pyridylmethyl)amine (tpa) skeleton; the formation of tpaCO2 in the reaction highlights the instability of pyridylmethylamines to oxidative cleavage, which has implications for the long-term stability of catalysts prepared from such ligands.
Keywords: Coordination chemistry; Tris(2-pyridylmethyl)amine ligand; Cobalt complex; Crystal structure; Oxidation catalyst stability;

An aqua-adenine H-bonding interaction controlling the formation of the rare Zn(II)–N9(adenine) bond in crystal structure of diaqua(adenine)(iminodiacetato)zinc(II) by A.C. Morel; D. Choquesillo-Lazarte; C. Alarcón-Payer; J.M. González-Pérez; A. Castiñeiras; J. Niclós-Gutiérrez (1354-1357).
In the 3D H-bonded crystal of [Zn(IDA)(AdeH)(H2O)2], with IDA=iminodiacetato and AdeH=adenine ligands, the molecular recognition between the Zn(IDA) chelate and AdeH is made by the rare Zn–N9(AdeH) bond reinforced by an intra-molecular O–H(aqua)⋯N3(AdeH) interaction. There are also AdeH:AdeH and IDA:AdeH pairing by double inter-molecular H-bonding interactions.A novel mixed-ligand zinc(II) complex with iminodiacetato(2-) (IDA) and adenine (AdeH) ligands has been obtained. Its crystal consists of octahedral molecules [Zn(IDA)(AdeH)(H2O)2] where the selective Zn–N9(AdeH) bond, involving the most basic N(AdeH) donor atom, occupies the trans position versus the Zn–N(IDA) bond. The Zn(II)–N9(AdeH) binding mode seems to be rare enough in comparison to those previously reported for Zn(II) and AdeH or a variety of related ligands. The chelate-nucleobase recognition process is further accomplished by an O–H(aqua)⋯N3(adenine) inter-ligand H-bonding interaction, without any intra-molecular IDA–nucleobase interaction. This finding is attributed to the polarizing effect of Zn(II) on the aqua ligand and the possibilities of AdeH acting as N-donor for the metal(II) atom and H-acceptor for an intra-molecular inter-ligand H-bonding interaction. There are no aromatic π,π-stacking contributions in the 3D H-bonded network, where all polar N–H (IDA or AdeH) and O–H (aqua) bonds are involved as donors in H-bonding interactions, which include AdeH:AdeH and IDA:AdeH pairing by double inter-molecular bridges.
Keywords: Crystal structure; Adenine; Iminodiacetate; Zinc(II); Molecular recognition; H-bonding; Inter-ligand interactions;

The reaction of cis-Re2(μ-O2CCH3)2Cl4(H2O)2 with picolinic acid (Hpic) affords either the diamagnetic, metal–metal bonded, dirhenium(III) complex Re2(μ-OMe)(μ:η2-pic)(η2-pic)3Cl (1) or the mononuclear rhenium(V) complex ReO(η2-pic)2Cl (2), depending on whether mixed methanol/ethanol or acetone/ethanol solvent mixtures are used. The structures of 1 and 2 have been established by X-ray crystallography. Complex 1 is unusual in having a bridging methoxide and bridging picolinate ligand in an edge-sharing bioctahedral structure in which the Re–Re bond distance of 2.4588(4) Å is unusually short for what is a formal Re–Re double bond.
Keywords: Dirhenium(III) complex; Rhenium(V) complex; Multiple metal–metal bonds; Pyridine-2-carboxylic acid (picolinic acid);

The hydrothermal reaction of NH4VO3, Co(NO3)2  · 6H2O, 2,2-bipyridine, H3BO3 and H2O at 170 °C yields the new complex [Co(2,2-bipy)(H2O)(VO3)2]. The structure consists of layers, each a two-dimensional network built up of corner-sharing VO4 tetrahedral chains interconnected through [Co(2,2-bipy)(H2O)]2+ groups, and there exists a weak antiferromagnetic exchange interaction between the cobalt ions in the layers.
Keywords: Crystal structures; Vanadium complexes; Cobalt complexes; Hydrothermal synthesis; Magnetic properties;

A systematic investigation of the reactions of 3d-metal ions with succinamate(−1) (LH) in the presence of aromatic N,N -donors has been initiated and initial results are described. Several reaction schemes involving various copper(II) sources, LH and 4,4-dimethyl-2,2-bipyridine (dmbpy) or 2,2-bipyridine (bpy) afforded the new complexes [Cu2(LH)3(dmbpy)2](OH) · H2O · MeOH (1a), [Cu2(LH)2(dmbpy)2(H2O)2](ClO4)2  · 2H2O (2), [Cu4(LH)5(dmbpy)4] n (ClO4)3n  ·  nH2O · 0.53nMeOH (3) and [Cu2(OH)(H2O)(LH)(bpy)2](ClO4)2 (4), which have been characterized by single-crystal X-ray crystallography and IR spectroscopy. The dinuclear complexes contain extremely rare cores, while the novel cationic coordination polymer 3 consists of alternating dinuclear units.
Keywords: Coordination polymers; Copper(II) complexes; Crystal structures; N,N -Donor ligands; Succinamate(−1) ligand;

A series of 2-imino-indole derivatives and their neutral nickel complexes were synthesized and characterized. A single-crystal X-ray analysis of [Ni(C10H7)(C18H16ClN2)(PPh3)] shows the nickel center adopted a square-planar coordination geometry. The nickel complexes act solely as effective catalysts for ethylene oligomerization with the activity up to 2.05 × 104 g ethylene mol−1 h−1.
Keywords: Neutral nickel complex; Indole; Schiff base; Ethylene oligomerization; Crystal structure;

Synthesis, crystal structure and second harmonic generation of (DMAPM+)[Cd(DMAP)I3] by Peng Ren; Jingui Qin; Fuying Du; Tao Liu (1375-1377).
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).
Keywords: Hybrid; Synthesis; Crystal structure; Second harmonic generation;

1-(4-Methoxyphenyltelluro)-2-[3-(6 methyl-2 pyridyl)propoxy]ethane (L 1 ) and its complexes [MCl2(L 1 )]2 (M = Pd or Pt) have been synthesized. The single crystal X-ray diffraction of [PtCl2(L 1 )]2  · 2CHCl3 shows a bimetallic complex of platinum(II) containing a 20-membered metallomacrocycle ring, which remains stable in solution as shown by molecular weight and conductance measurements. The Pt–Te and Pt–N bond lengths are 2.5409(3) and 2.087(5) Å, respectively. The protons of CH2 linked to Te show a deshielding > 1 ppm on the formation of the two complexes.
Keywords: Platinum; Complex; 1-(4-Methoxyphenyltelluro)-2-[3-(6 methyl-2 pyridyl)propoxy]-ethane; Hybrid organotellurium ligand; Crystal structure; Synthesis;

The reaction of phenyl(alkynyl)iodine(III) triflates with diorganoplatinum(II) complexes provides a general route for the synthesis of a new class of alkynylplatinum(IV) complexes containing PtIVR2(CCR2) groups, e.g., the 4,4-bis(tert-butyl)-2,2-bipyridine complexes PtIR2(CCSiMe3)(Bu t 2bpy) (R=Me, Ph); IPh2(OTf) reacts with PtPh2(Bu t 2bpy) to form the first archetypal triarylplatinum(IV) complex PtIPh3(Bu t 2bpy).
Keywords: Organoplatinum(IV); Triphenylplatinum(IV); 2,2-Bipyridine; Alkynyls; Iodonium; Iodine(III);

Hydrazinium lanthanide 2,3-pyrazinedicarboxylate hydrates of composition (N2H5)[Ln(pyz(COO)2)2 (H2O)] · nH2O, (pyz(COO)2=2,3-pyrazinedicarboxylate), where Ln=La, Pr and Nd if n=4 and Ln=Sm, Dy and Ce if n=0, have been prepared and characterized by physico-chemical methods.
Keywords: Hydrazinium cation; Infrared spectra; 2,3-Pyrazinedicarboxylic acid; Rare-earth metals; Thermal studies;

Shape-controlled synthesis of submicro-sized cuprous oxide octahedra by Xu Zhang; Yi Xie; Fen Xu; Xiaohui Liu; Di Xu (1390-1392).
Monodisperse submicro-sized cuprous oxide (Cu2O) octahedra are successfully prepared in large quantities assisted by the capping reagent poly(vinyl pyrrolidone) (PVP-K30, MW=58 000) and the formation mechanism of Cu2O octahedra is analyzed.
Keywords: Cu2O octahedra; Anion coordinative polyhedra; PVP; Growth units;

Inducing synthesis of CdS nanotubes by PTFE template by Zhen-Lei Zhang; Qing-Sheng Wu; Ya-Ping Ding (1393-1394).
Using PTFE membrane as structure-directing template, the CdS nanotubes with the internal diameter of 100–130 nm, the wall thickness of 15–18 nm, and the length of about 1.4 μm were inductively synthesized.
Keywords: CdS; Nanotubes; Membrane; Inducing synthesis;

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.
Keywords: Trinuclear complex; Copper(II); Nickel(II); Crystal structure; Magnetic properties;

(Terpyridine)(acetylacetonate)ruthenium(II) complex with a zwitterionic form of phosphoniophenylcyanamide ligand by Lucinda Dudd; Matthew Hart; David Ring; Elodie Sondaz; Jacques Bonvoisin; Yannick Coppel (1400-1405).
The complex [Ru(tpy)(acac)(PPh4cyd)][PF6] (where tpy: 2,2:6,2″-terpyridine, acac: acetylacetone and PPh4cyd: 4-triphenylphosphoniophenylcyanamide) has been synthesized. It contains the zwitterionic form of the phosphoniophenylcyanamide ligand. Characterizations were carried out using IR, ES-MS, UV–Vis, electrochemistry and 1H, 13C and 31P NMR spectroscopy.
Keywords: Ruthenium(II) complex; Cyanamide; NMR; Zwitterion; Phosphonium;

Fabrication and characterization of hollow cuprous sulfide (Cu2−x S) microspheres by a simple template-free route by Yonghong Ni; Fei Wang; Hongjiang Liu; Yongye Liang; Gui Yin; Jianming Hong; Xiang Ma; Zheng Xu (1406-1408).
The hollow Cu2−x S microspheres were successfully prepared via a novel template-free route in a simple system containing CuSO4, Na2S2O3 and H2O at the ambient conditions. A possible formation mechanism was proposed.

A novel method for making CuO superfine fibres via an electrospinning technique by Hongyu Guan; Changlu Shao; Bin Chen; Jian Gong; Xinghua Yang (1409-1411).
Thin PVA/copper acetate composite fibres were prepared by using sol–gel processing and electrospinning technique. After calcinations of the above precursor fibres, CuO superfine fibres with a diameter of 100–200 nm could be successfully obtained. The fibres were characterized by SEM, FT-IR, XRD, respectively.

The hydrothermal reaction of Cu(OAc)2  · H2O with thiophene-2,5-dicarboxylic acid (H2tdc) and 4,4-bipyridine (bpy) gave a copper(II) coordination polymer {[Cu(tdc)(bpy)(H2O)](bpy)} n (1), in which the (4,4) layers are assembled via strong hydrogen bonds between the aqua ligands and the uncoordinated carboxylate oxygen atoms into a porous 3-D molecular architecture with parallelogrammic channels. The guest bpy molecules reside in the channels, involving intermolecular C–H⋯N hydrogen bonds with the host framework, can be removed upon heating at reduced pressure.
Keywords: Copper; 4,4-Bipyridine; Thiophene-2,5-dicarboxylate; Hydrogen-bonding interaction; Guest molecules;