Inorganic Chemistry Communications (v.5, #5)

Contents List (iii-iv).

Observation of photoluminescence in a Cu I (amino N)2(imino N)2 chromophore at room temperature and 77 K by Subhasis Panja; Shubhamoy Chowdhury; Michael G.B. Drew; Dipankar Datta (304-307).
A moderately air stable Cu I (amino N)2(imino N)2 chromophore having a Cu(II/I) potential of 0.12 V vs SCE is isolated using a tetradentate N-donor ligand and characterised structurally by X-ray crystallography. It is found to be photoluminescent in fluid solution at room temperature as well as in frozen solution at 77 K.
Keywords: Schiff base; Copper(I) complex; Crystal structure; Electrochemistry;

The decatungstomolybdoniobogermanic heteropoly acid H5[GeW10MoNbO40]·20H2O has been prepared for the first time. The optimal proportion of the solutions of the component and the pH of the synthesis reaction are given. The product was characterized by chemical analysis, conductometric and potentiometric titration, IR, UV, XRD, 183W NMR and TG-DTA. The IR, UV, XRD and 183W NMR indicate that H5[GeW10MoNbO40]·20H2O possesses the Keggin structure. The TG-DTA curve shows the sequence of water loss in the acid, the amount of the loss as well as the thermostability of the acid.
Keywords: Heteropoly acid; Deca-tungstomolybdoniobogermanic acid; Preparation; Characterization;

The substituent effect on the oxidation site of azaferrocene was studied by using 1H NMR and 57Fe Mössbauer spectroscopy. An introduction of methyl substituent to the cyclopentadienyl ring promotes the oxidation of the central iron atom of azaferrocene more than the nitrogen atom in pyrrole ring, which is contrary to the introduction of methyl substituent to the pyrrole ring. Broadening and shift of NMR signals were observed by successive adding of iodine into the 1,2,2,3,4,5,5-heptamethylazaferrocene and then narrowing was observed by further adding of iodine, suggesting a structural change by iodine oxidation.
Keywords: Azaferrocene derivatives; Structural change; Iodine oxidation; Substituent effect;

Insights in the sol–gel processing of Pb(Mg1/3Nb2/3)O3. The synthesis and crown structure of a new lead magnesium cluster: Pb6Mg12(μ-OAc)622-OAc)1832-OC2H4OPri)12 by Stephane Parola; Roland Khem; David Cornu; Fernand Chassagneux; Sylvain Lecocq; Zian Kighelman; Nava Setter (316-318).
The synthesis and molecular structure of a Pb–Mg bimetallic acetatoalkoxide (Pb6Mg12(μ-OAc)622-OAc)1832-OC2H4OPri)12, space group R-3, a=b=30.032(2), c=18.855(2) Å, α=β=90°, γ=120°) are discussed in this article. This compound was isolated as an intermediate during the elaboration of Pb(Mg1/3Nb2/3)O3 (PMN) using sol–gel process. It results from the reaction of a bimetallic Mg/Nb species with lead acetate in 2-isopropoxyethanol.
Keywords: Lead complexes; Magnesium complexes; Alkoxide; Acetate; Sol–gel; PMN;

Cationic olefin Pd(II) complexes bearing α-iminoketone N,O-ligands: unprecedented isomerisation of the methoxycyclooctenyl ligand by Alceo Macchioni; Cristiano Zuccaccia; Barbara Binotti; Carla Carfagna; Elisabetta Foresti; Piera Sabatino (319-322).
The reaction of [Pd(η12-C8H12OMe)Cl]2 with α-iminoketone ligands affords cationic η12-5-methoxycyclooctenyl Pd(II) complexes, the intramolecular and interionic structures of which were investigated in both solution and solid state; such complexes undergo unprecedented isomerisation to η12-1-methoxycyclooctenyl complexes assisted by weak nucleophiles such as olefins or alkynes.
Keywords: Palladium compounds; N,O-ligands; X-ray structure; 1D- and 2D-NMR spectroscopy;

Hexa(2-pyridyl)[3]radialene was prepared by reaction of di-2-pyridylmethane with tetrachlorocyclopropene. Reaction of this ligand with silver nitrate and silver hexafluorophosphate gave two different one-dimensional coordination polymers each with a 2:1 metal–ligand composition. X-ray crystal structures revealed that the structure and topology of the coordination polymer is strongly influenced by the anion. In the reaction with silver nitrate the ligand self-assembled to give a helical one-dimensional coordination polymer, but when silver hexafluorophosphate was used, a coordination polymer, composed of Ag3L2 prismate cages linked by linear-bridging silver atoms, was obtained.
Keywords: Crystal structures; Metallosupramolecular chemistry; Self-assembly; Silver complexes; Coordination polymers;

Control of the spin state of Fe(II) 2,6-di(pyrazol-1-yl)pyridine complexes by distal ligand substitution by Joanne M. Holland; Simon A. Barrett; Colin A. Kilner; Malcolm A. Halcrow (328-332).
The complexes [Fe(L1R)2]X2 (L1R = 2,6-bis-{3-iso-propylpyrazol-1-yl}pyridine[L1Pri], X=BF4 or PF6 ; L1R = 2,6-bis-{3-phenylpyrazol-1-yl}pyridine [L1Ph], X=BF4 ) are high-spin between 5 and 300 K in the solid, and between 180 and 300 K in acetone solution. In contrast, [Fe(L1Mes)2]X2 (L1Mes = 2,6-bis-{3-[2,4,6-trimethylphenyl]pyrazol-1-yl}pyridine, X=BF4 or PF6 ) are fully low-spin at 300 K in the solid and solution phases. This shows that the spin state of the Fe ion in these compounds depends on the inductive properties of the ligand 3,3″-substituents only, as long as those substituents are aromatic.
Keywords: Iron complexes; Magnetic properties; Crystal structure;

Reaction of hydrazine with the octanuclear mixed valence oxothioanion [MoV 8S8O8(OH)8{HMoVIO5(H2O)}]3− has afforded the octanuclear anion [MoV 8S8O8(OH)7(N2H4)2{MoVIO4}] as potassium salt. Its structure has been established by X-ray crystallography, showing that four of the hydroxo bridges have been replaced by μ2-N2H4 ligands. Concomitantly the coordination of the central MoVI atom has changed from octahedral to tetrahedral. In the solid, the anionic rings are attached to double chains of potassium ions.
Keywords: Polyoxometalate; Hydrazine complex; Crystal structure; Molybdenum;

Synthesis, structure and characterisation of a Mn(IV) complex with a potentially tridentate phosphinothiol ligand by Paulo Pérez-Lourido; Jaime Romero; Laura Rodrı́guez; José Arturo Garcı́a-Vázquez; Jesús Castro; Antonio Sousa; Jonathan R. Dilworth; Otaciro R. Nascimento (337-339).
The manganese(IV) complex, [Mn{PhP(C6H4S-2)2}2], was synthesised by direct reaction between manganese(II) acetate and the proligand bis(2-mercaptophenyl)phenylphosphine in methanol and characterised by elemental analysis, mass spectrometry, cyclic voltammetry and X-ray crystallography.
Keywords: Crystal structure; Mn(IV) complexes; Phosphinothiolate complexes; Cyclic voltammetry;

A new polidentate ligand, 3,5-diacyl-1,2,4-triazolebis(4-methylthiosemicarbazone), (H5L) has been synthesised; complexation of this ligand with Li2PdCl4 leads to a novel stable [Pd2(μ-H3L)2] macrocyclic cage which was characterised by X-ray crystallography. The ligand coordinates to the Pd atoms in a new tridentate fashion, forming a chelating and a bridging bonding modes.
Keywords: Palladium(II) complexes; Bis(thiosemicarbazone); 1,2,4-Triazoles; Crystal structure;

Molecular structure of [In2(μ,η1-OR)(μ,η2-OR)(η2-OR)31-OR)] R = C2H4NMe2, a pincer ligand by Stephane Daniele; Dimitry Tcheboukov; Liliane G. Hubert-Pfalzgraf; Sylvain Lecocq (347-350).
Functional indium [In(OR)3] m alkoxides (R = C2H4OMe, C2H4NMe2) have been obtained by alcoholysis of In[N(SiMe3)2]3 and characterised by elemental analysis, FT-IR and NMR spectroscopy. The 2-dimethylaminoethoxide was characterised by X-ray diffraction. It corresponds to the association of two InO6 octahedra giving the unsymmetrical dimer [In2(μ,η1-OR)(μ,η2-OR)(η2-OR)31-OR)] (2). 2 was used as a pincer ligand toward Cu(acac)2.
Keywords: Indium; X-ray structure; Functional alkoxide; Copper;

The reactivity of mononuclear platinum and palladium dithiolato species as building blocks for homo- and heterobimetallic complexes is described. The heterobimetallic cationic complex [(PPh3)2Pt(μ-S(CH2)2S)Pd(dppb)](BF4)2 was obtained by reaction of [Pt(S(CH2)2S)(PPh3)2] with [PdCl2(Ph2P(CH2)4PPh2)] in presence of AgBF4.
Keywords: Heterobimetallic compounds; Platinum; Palladium; Dithiolates; Metalloligands;

Silver(I) complexes of selenourea (Seu), Ag(Seu)NO3 and Ag(Seu)2NO3 have been prepared and characterized by elemental analysis, IR and NMR (1 H,13 C,15 N and 107 Ag) spectroscopy. An upfield shift in 13 C NMR and downfield shifts in 1 H and 15 N NMR for selenourea resonances are consistent with the selenium coordination to Ag(I). In 107 Ag NMR, the AgNO3 signal is deshielded by more than 600 ppm on its coordination to selenourea.
Keywords: Silver(I); Complexes; Selenourea; NMR;

A novel 2-D coordination polymer constructed by μ2-acetate-O,O, μ2-hydroxo, μ2-aqua and 4,4-bipyridine (bipy) ligands has been synthesized and structurally characterized. Linear 1-D chain built by bridged μ2-acetate-O,O, μ2-hydroxo and μ2-aqua units is composed of Cu2O2 motifs and syn-anti bridged acetate ligands. The copper atom with a five-coordination has a distorted square-pyramidal geometry completed by two nitrogen atoms from 4,4-bipyridine and three oxygen atoms from acetate, hydroxo and water ligands. The strong stacking effect is observed between 4,4-bipyridine ligands.
Keywords: Acetate complex; Hydroxide complex; Aqua complex; Coordination polymer;

[Na8Zn4(CH3CO2)16·2H2O] n : two-dimensional sheet-like coordination polymer with strong blue emission by Lei Z. Zhang; Peng Cheng; Wei Shi; Dai-Zheng Liao; Ying Xiong; Guo-Qing Tang (361-365).
A novel heteronuclear compound, [Na8Zn4(CH3CO2)16·2H2O] n 1, with an unusual two-dimensional condensed polymeric structure was successfully synthesized. 1 crystallizes in the triclinic space group P-1, a=9.3332(19) Å, b=10.511(2) Å, c=16.152(3) Å, α=79.78(3)°, β=83.82(3)°, γ=64.85(3)°, V=1410.6(5)  A ̊ 3 , Z=2. The most striking feature of 1 is that the bridging acetate ligands show four coordination modes within one compound. The luminescence studies show strong blue photoluminescence as the result of the fluorescence from the intraligand emission excited state.
Keywords: Zinc; Two-dimensional coordination polymer; Crystal structure; Luminescence;

Syntheses and characterizations of two novel Ln(III)–Cu(II) coordination polymers constructed by Pyridine-2,4-dicarboxylate ligand by Yucang Liang; Rong Cao; Maochun Hong; Daofeng Sun; Yingjun Zhao; Jiabao Weng; Ruihu Wang (366-368).
Two novel three dimension Ln(III)–Cu(II) coordination polymers [Gd2Cu(pydc)4(H2O)6] n and [Sm2Cu3(pydc)6(H2O)6] n were prepared by the hydrothermal reactions of CuO, Ln2O3 (Ln = Gd, Sm), H2pydc (H2pydc = 2,4-pyridinedicarboxylic acid) and characterized by single-crystal X-ray diffraction analysis.

α-MnSe crystallites through solvothermal reaction in ethylenediamine by Tian Qin; Jun Lu; Shuo Wei; Pengfei Qi; Yiya Peng; Zhiping Yang; Yitai Qian (369-371).
α-MnSe crystallites were prepared by solvothermal reaction in ethylenediamine at 190 °C. X-ray diffraction gave the α-MnSe phase of product, X-ray photoelectron spectroscopy indicated the valence state of Mn2+ and Se2−. The flaky morphology was found by the transmission electron microscope images. The optimal synthetic conditions were explored by using other nitrogen-containing solvents, and lowering the reaction temperature.
Keywords: Solvothermal; α-MnSe; Crystallites; Ethylenediamine;

Direct synthesis of bis(n-alkylammonium) monohydrogen phosphates by solid–vapour reaction by Camino Trobajo; Aránzazu Espina; Sergei A. Khainakov; José R. Garcı́a (372-375).
n-Alkylamines (C n H 2n+1 NH 2, n=2–6) have been intercalated into orthophosphoric acid by exposing the solid to the vapour of the amines. Compounds were obtained of both the (C n H2n+1NH3)(H2PO4) and (C n H2n+1NH3)2(HPO4)·H2O formulae. In the novel monohydrogen phosphates, n-alkylamines form a bimolecular film inclined an average of 42.6° with respect to the phosphate layer plane. These compounds are proposed as starting materials for the hydrothermal synthesis of new open-framework metal phosphates.
Keywords: Phosphates; Amines; Intercalation; Solid–vapour reactions;