Inorganic Chemistry Communications (v.81, #C)

Contents List (iii-vi).

High temperature ionic conduction mediated by ionic liquid incorporated within the metal-organic framework UiO-67(Zr) by Li-Hong Chen; Bin-Bin Wu; Hai-Xia Zhao; La-Sheng Long; Lan-Sun Zheng (1-4).
IL@MOF (IL = ionic liquid; MOF = metal organic framework) as a new type hybrid ionic conductor has attracted research interest. Ionic liquids incorporated within MOFs not only promote the ionic conductivity of ILs, but also mediate the working temperature. In our report, 1-Ethyl-3-methylimidazolium Chloride (EMIMCl) was introduced into the pores of UiO-67(Zr) MOF by taking simple strategy basing on capillary action through specific grinding and diffusing in heating process. The working temperature of EMIMCl@UiO-67 is up to 200 °C. And it shows high ionic conductivity (1.67 × 10− 3  S·cm− 1 at 200 °C). The activation energy was estimated to be 0.37 eV. It is noteworthy that the hybrid material can be regarded as a fast-ion conductor based on the value of high conduction and low E a. The high-temperature and humidity-independent ion conduction as well as low activation energy make this material potentially useful for electrochemical devices.EMIMCl@UiO-67 as a new hybrid humidity-independent fast-ion conductor could work in high temperature up to 200 °C.Display Omitted
Keywords: Ionic conductivity; Ionic liquid; IL@MOF; Fast-ion conductor;

The synthesis and physico-chemical characterization of an organic-inorganic hybrid material, (N, N'-bi-n-butyl-4,4′-bipyridinium tetrabromocuprate, has been reported. This hybrid has been characterized using IR, thermogravimetric and single-crystal X-ray diffraction analyses. In the title salt, (C18H26N2)[CuBr4], the CuBr4 2 − ion shows distorted tetrahedral geometry. The tetrabromocuprate and N, N'-bi-n-butyl-4,4′-bipyridiniums are held together via non-classical C―H ⋯ Br hydrogen bond to form a 3-D hybrid structure. The percentages of hydrogen bonding interactions are analyzed by fingerprint plots of Hirshfeld surface. The XPS spectrum exhibits the signals of coexistence of CuI and CuII ions. However, the hybrid shows EPR silent behavior at room temperature and variable-temperature magnetic susceptibility displays an isolation of CuII feature with C  = 0.46 emu K mol− 1 and θ approximate to − 0.06 K in 2– K as well. Such a novel nature is further analyzed and discussed.A new organic-inorganic hybrid crystal material (C18H26N2)[CuBr4] has been synthesized. This hybrid shows novel XPS spectroscopy and EPR silent behavior at room temperature. The variable-temperature magnetic susceptibility displays an isolation of CuII feature.Display Omitted
Keywords: Tetrabromocuprate; Crystal structure; Hirshfeld surface; Magnetic properties; XPS spectrum;

Facile fabricating the polyoxometalates functionalized graphene nanocomposite applied in electrocatalytic reduction by Xiangyan Wei; Jiawei Wei; Liping Huang; Tingting Yan; Fang Luo (10-14).
The well dispersed and porous PMo12-rGO nanocomposite was synthesized via a chemical reduction method by the facile and economical reducing agent of thiourea. By optimizing the amount of reducing agent of thiourea, PMo12 was reduced to heteropoly blue, and then reacted with GO to assemble PMo12 clusters onto the rGO by the strong interaction between rGO and PMo12. The SEM, HTEM, FT-IR, UV–vis, XPS and Raman were performed to verify the structure of the PMo12-rGO nanocomposite. The as-prepared PMo12-rGO nanocomposite exhibits high stability and excellent electrocatalytic activity towards the reduction of nitrite and hydrogen peroxide compared with individual PMo12 catalysts, which could be mostly attributed to the synergistic effects of rGO and PMo12. The method is facile, economical and suitable for mass production and common POMs, which opens a new way to fabricate a wide range of hybrid materials using different type of polyoxometalates, and such as-prepared materials have potential applications in catalysis, electrochemisty and related fields.Polyoxometalates (POMs) are reduced to heteropoly blue by facile and economical reducing agent-thiourea, which subsequently react with GO to assemble POMs clusters onto the rGO by the strong interaction between rGO and POMs.Display Omitted
Keywords: Polyoxometalates; Electrocatalytic reduction; Graphene;

Assembly of CdCl2 and 3,3′-dimethoxy-2,2′-bipyridine-6,6′-dicarboxylic acid (H2mbpdc) under hydrothermal condition affords a chloride-centered discrete CdII 6 cage [Cd6(mbpdc)6Cl]·[H(H2O)14.5] (1), in which a cationic water cluster H+(H2O)10 is present. Our anion-templated assembly system exhibits exclusive encapsulation of Cl ion, and thus displays potentially applications in the separation of Cl ion with other halide ions.A chloride-centered cage has been isolated. The anion-templated assembly system can be acted as selective Cl ion receptors in competitive aqueous solutions and thus can be potentially applied in molecular recognition and separations.Display Omitted
Keywords: Templated assembly; Cage; Anion recognition; Selection separation;

Binaphthol-strapped chiral bis(porphyrinato) cerium double-decker complexes by Wenxin Lu; Chiming Wang; Xinyao Li; Xiaopeng Zhan; Dongdong Qi; Yongzhong Bian (18-21).
(R)-(+)- or (S)-(−)-1,1′-bi-2-naphthol (BINOL) was applied as a remote chiral auxiliary to connect the two facing porphyrin rings, resulting in the BINOL-strapped chiral bis(porphyrinato) cerium double-decker complexes (R)-/(S)-1 and (R)-/(S)-2, which were carefully characterized by a range of spectroscopic and electrochemical methods. Perfect mirror images were observed in their circular dichroism (CD) spectra with a negative sign in the Soret band for (R)-enantiomers and a positive sign for (S)-enantiomers, which suggests the C 2 -chirality of a BINOL strap is transcribed to the double-decker core as a defined chiral twist in the inter-porphyrin arrangement. Furthermore, the CD intensities of (R)-/(S)-1 are always larger than those of (R)-/(S)-2, indicating that the intramolecular chirality transfer efficiency can be finely tuned by changing the length of interlocking moieties.Two pairs of BINOL-strapped chiral bis(porphyrinato) cerium double-decker complexes were synthesized and characterized by a range of spectroscopic and electrochemical methods. The CD spectra suggest that the chirality of a BINOL strap can be translated to a defined chiral twist between the two facing porphyrin rings with tunable efficiency.Display Omitted
Keywords: Porphyrin; Binaphthol; Cerium; Chirality; Circular dichroism spectrum;

A novel 3D supramolecular compound assembled from Strandberg-type polyoxometalate and benzimidazole [Hbiz]5[HMo5P2O23]·5H2O (1, biz = benzimidazole) was synthesized with a convenient aqueous solution method and structurally characterized through single-crystal X-ray diffraction, elemental analysis, IR and UV–vis spectrum analyses. Single-crystal X-ray analysis revealed that the title compound crystallized in the monoclinic system space group P21/c with a  = 11.415(2), b  = 33.311(7), c  = 13.941(3) Å, β  = 99.2279(3)°, V  = 5232.0(18) Å3, and Z  = 4. Compound 1 was composed of one [HMo5P2O23]5 − polyanion, five protonated biz cations, and five crystal water molecules; it displayed a 3D supramolecular structure through electrostatic attraction, hydrogen bonding, and π–π interactions. The experiment on anti-tumor activities in vitro showed that compound 1 inhibited human neuroblastoma SHY5Y cells and demonstrated dose dependency and selectivity.Compound 1 was composed of [HMo5P2O23]5 − polyanions and protonated biz cations, and five crystal water molecules, forming a 3D supramolecular structure. The experiment on anti-tumor activities in vitro showed that compound 1 inhibited human neuroblastoma SHY5Y cells and demonstrated dose dependency and selectivity.Display Omitted
Keywords: Polyoxometalate; Strandberg type; Supramolecular structure; Antitumor activity;

We have prepared and characterized five unreported ruthenium(II) and iridium(III) complexes supported by pyridine-functionalized N-heterocyclic carbene ligands including a bimetallic iridium(III) complex. When activated, all complexes are active catalysts for the transfer hydrogenation of acetophenone.Display Omitted
Keywords: N-heterocyclic carbene; Ruthenium(II); Iridium(III); Transfer hydrogenation; Bimetallic;

A new coordination polymer incorporating an unprecedented [Ni9S10] cluster as secondary building unit by Ning Yuan; Chongbin Tian; Tianlu Sheng; Shengmin Hu; Xintao Wu (33-36).
A novel coordination polymer formulated as Ni(H2O)6[Ni11(mna)10(dmdn)2(H2O)16]·(H2O)14 (1) (mna  = 2-mercaptonicotinate, dmdn  = dithiodinicotinate) has been hydrothermally synthesized by reacting nickel acetate tetrahydrate with 2-mercaptonicotinic acid and characterized by single-crystal X-ray diffraction along with powder X-ray diffraction (PXRD), infrared spectroscopy (IR), elemental analyses and magnetic analyses. Compound 1 features its unprecedented nonanuclear nickel-sulfur [Ni9S10] secondary building unit (SBU) in the extended structure. Furthermore, magnetic susceptibility measurements revealed that 1 displays overall anti-ferromagnetism interactions.A novel coordination polymer featuring unprecedented nonanuclear nickel-sulfur [Ni9S10] secondary building unit was synthesized and characterized.Display Omitted
Keywords: Nickel; Cluster; Secondary building unit; Coordination polymer; Magnetism; 2-mercaptonicotinic acid;

Nanostructures of a new copper-based metal-organic framework with a Schiff base ligand as an organic linker, Cu2 (bdda) (OAc)2·1H2O (H2bdda = 4,4′-[benzene-1,4-diylbis (methylylidenenitrilo)] dibenzoic acid), was prepared via Ultrasound assisted synthesis and characterized by X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), inductively coupled plasma atomic emission spectroscopy (ICP-AES), transmission electron microscope (TEM), elemental analysis (CHN) and FT-IR spectroscopy. Catalytic proficiency of this MOF in the oxidation of alcohols was investigated that exhibited efficient and selective activity for the transformation of alcohols to the corresponding carbonyl compounds under the absence of organic solvents. The reusability of the catalyst also was examined, in which the catalyst was reused six times without significant loss of its catalytic efficiency.Display Omitted
Keywords: MOF; Schiff base; Oxidation; TBHP; Alcohols;

The terminal > C=S group in 1,3-dithiole-2-thione-4,5dithiolate (dmit) ligand of (dppe)Pt(dmit) (dppe: 1,2-bis(diphenylphosphino)ethane) is known to be coordinated to Hg2 + ion. This is clearly shown by the bathochromic shift of the π → π transition band in H2O/CH3CN solution (1:1 v/v). The band shifts are strongly anion-dependent. An equimolar amount of HgX2 (Group I: X = ClO4 , TfO, CH3SO3 , ½SO4 2 −, AcO, and F) led to the bathochromic shift, because of strong > C=S ⋯ Hg2 + interaction. In contrast, a mixed band (Group II: X = Br, Cl, and SCN) or no band shift (Group III: Hg(CN)2 and Hg2Cl2) was observed, because of the strong interaction between Hg2 + and the anions. These results are related to the binding constant (K) of Hg2 + ion with (dppe)Pt(dmit) chemosensor. The binding constants of Hg(ClO4)2 (K  = 2.3 × 106) and Hg(OTf)2 (K  = 2.0 × 106) are larger than those of Group II and III, resulting in complete bathochromic shift of the π → π transition at [Hg2 +]/[(dppe)Pt(dmit)] = 0.4.The solution colors of HgX2/(dppe)Pt(dmit) depend on the binding constant of (dppe)Pt (dmit)⋯ Hg2 +.Display Omitted
Keywords: Hg2 +-sensing; Pt-dithiolene; Binding constant; Job's plot;

Synthesis, structure, magnetic properties of a 2D (3,4,5)-connected framework based on the tetranuclear Cu4 units by Yanquan Duan; Jianhao Huang; Sicong Liu; Tiantian Yu; Jinpeng Li; Yaping Hao; Zhongyi Liu; Bin Liu (47-50).
Based on an asymmetric imidazole-1-acetic acid (Hima), a new polynuclear complex [Cu2(ima)(SO4 2 −)(H2O)(OH)] n 1 has been synthesized and characterized structurally and magnetically. Polymer a two-dimensional (2D) structure based on the tetranuclear Cu4 units, which displays a (3,4,5)-connected topology. The magnetic susceptibility data is dominated by magnetic interactions associated with the hydroxo bridges arising from different Cu-OH-Cu angles, which is in agreement with magneto-structural correlations found in the literature relative to such bridges in Cu(II) complexes.Complex 1 shows (3,4,5)-connected 2D structure based on the tetranuclear Cu4 units. Magnetic studies reveal magnetic interactions associated with the hydroxo bridges arising from different Cu-OH-Cu angles.Display Omitted
Keywords: Metal-organic framework; Tetranuclear Cu4; Topology analysis; Magnetic properties;

Gold(I) phosphine complexes with bis(2-pyridyl)diselenoether: Synthesis and structure elucidation by Roberta Cargnelutti; Felipe D. da Silva; Rodrigo Cervo; Ricardo F. Schumacher; Ernesto S. Lang (51-54).
Bis(2-pyridyl)diselenoether with the general formula (2-PySe)2(CH2) (L) reacts with Ph3PAuCl and [(dpph)(AuCl)2] dpph = 1,6-bis(diphenylphosphino)hexane to produce the respective complexes [(L)Au2(PPh3)2](PF6)2 (1) and [(L)(dpph)Au2(PF6)2] n (2). These complexes were isolated in crystalline form and studied using spectroscopic and X-ray diffraction techniques. The coordination of the ligand (2-PySe)2(CH2) (L) to the gold(I) metal centers in complexes [(L)Au2(PPh3)2](PF6)2 (1) and [(L)(dpph)Au2(PF6)2] n (2) occurs via the nitrogen atom of the pyridine ring, with no interaction with the selenium atoms of the bis(2-pyridyl)diselenoether. The gold derivative (Ph3PAuCl or [(dpph)(AuCl)2]) is responsible for the formation of a molecular complex (1) or a polymeric complex (2), and in both compounds the gold(I) metal atoms adopt an almost linear geometry.Display Omitted
Keywords: Selenium; Bis(2-pyridyl)diselenoether; Gold; Complex; X-ray structure;

Photochromism adjustment by the conjugation of electron-withdrawing ligand in two metal organic complexes by Chun-Hong Tan; Xi-Lin Xiao; Xiao-Feng Wang; Hong-Qing Wang; Ying-Wu Lin (55-58).
Understanding the photochromic mechanism of MOCs, regulating and controlling their structure and related photochromic properties is one of the focuses of chemistry and materials science. In this paper, two isoreticular metal-organic complexes have been synthesized by reaction of Zinc nitrite and H6ttha in the presence of bpee or bpea as co-ligand, respectively. The photochromic properties of complex 1 and 2 have been investigated. Even though both complexes holding similar framework, it is intriguing that complex 1 with conjugated co-ligand bpee displays remarkable photochromism property, but this photochromic phenomenon almost disappears in complex 2 when the conjugated co-ligand bpee is replaced by the non-conjugated coligand bpea. The possible photochromic mechanism is illustrated in detail. What's more, the relationship of structure-property has been discussed.The 3-D zinc-organic complex with the conjugation bpee co-ligand features the reversible photochromism performance under UV irradiate and heating derived from the radical medium state, while it cannot display similar property with the conjugated bpee being replaced by the non-conjugated bpea in a isoreticular framework.Display Omitted
Keywords: Metal organic complexes; Photochromism; Mechanism; Crystal structure;

PH-dependent fluorescence sensing activities of two water-stable 2-D zinc(II) compounds by Ranran Ma; Zhiwei Chen; Suna Wang; Changhui Zhou; Yunwu Li; Jing Lu; Dacheng Li; Jianmin Dou (59-66).
Two 2-D Zn(II) compounds, namely, [Zn(HL1)(bpy)]n (1) and {[Zn(HL2)(bpe)]·0.5bpe}n (2) (H3L1 = 5-(2′-carboxyl phenoxy)isophtalic acid, H3L2 = 1,3-bis(2-carboxylphenoxy)benzoic acid, bpy = 4,4′-bipyridine, bpe = 4,4′-vinylenedipyridine), have been solvothermally synthesized from two flexible phenolic carboxylic acid ligands. Both compounds exhibit 2-D layered structures with 4-conneted 44 and 3- connected 63 topology, respectively. PXRD indicated that these compounds were stable in the basic conditions with pH range of 7–11 and their fluorescence intensities are strongly correlated with the pH value. The protonated carboxylic groups may have influences on the resulting fluorescence intensities. The possible proton transfer mechanism was discussed for such pH sensors in details through FTIR and ICP measurements. In addition, the analytical efficiency and accuracy in practical applications of these sensors were performed on the real lake water.Two water-stable 2-D Zinc(II) compounds were reported with pH-dependent fluorescence sensing activities.Display Omitted
Keywords: Zn(II) compounds; pH-dependent fluorescence; Flexible phenolic carboxylic acid ligand;