Inorganic Chemistry Communications (v.9, #7)

Contents List (iii-ix).

Interaction of CoCl2 and [Ta(OMe)5] produced a small amount of the ionic [ Co 2 Ta 2 ( OMe ) 12 ( MeCN ) 4 ] 2 + [ CoCl 3 ( MeCN ) ] 2 - · 2 MeCN (1). Rational synthesis of this potential polymerization catalyst was achieved by reaction of [NaTa(OMe)6] with 4 eq. of CoCl2 in toluene/acetonitrile to give a new form [Co2Ta2(OMe)12(MeCN)4][CoCl3(MeCN)]2 (2).Ionic or ionogenic alkoxides are attractive potential catalysts for polymerization reactions. Direct interaction between CoCl2 and [Ta(OMe)5] produced, by self-assembly, a small amount of ionic aggregate clathrate with acetonitrile, [ Co 2 Ta 2 ( OMe ) 12 ( MeCN ) 4 ] 2 + [ CoCl 3 ( MeCN ) ] 2 - · 2 MeCN ( 1 ) . The structure of 1 contains a planar M4(μ 3-OR)2(μ-OR)4-core that can be considered as a fragment of hexagonal packing of metal and ligand atoms completed by 6 (3 + 3) terminal alkoxide ligands at the tantalum and 4 (2 + 2) terminal acetonitrile molecules at the cobalt atoms that are bearing the (+1) positive charge each. A rational synthesis of this compound was achieved by reaction between [NaTa(OMe)6] with four equivalents of CoCl2 in toluene/acetonitrile to give a new crystallographic form [Co2Ta2(OMe)12(MeCN)4] [CoCl3(MeCN)]2 (2), not containing interstitial solvent molecules.
Keywords: Heterometallic alkoxide cation; Cobalt; Tantalum; Polymerization catalyst;

Anion-controlled assemblies from pseudo-cyclic cadmium(II) complex and spacer coligand by Ki-Min Park; Seok-Tae Moon; Young Jin Kang; Hyun Jee Kim; Joobeom Seo; Shim Sung Lee (671-674).
Self-assembly reactions between the dipodal ligand L with Cd(ClO4)2 and Cd(NO3)2 afforded unique pseudo-cyclic complexes (A) [Cd(L)(H2O)(CH3OH)](ClO4)2 (1) and [Cd(L)(H2O)(NO3)](NO3) (2), respectively. From the stepwise reaction of the pseudo-cyclic complexes (A) followed by coligands (B) such as 4,4′-bipyridine and terephthalate, we isolated the controlled one-dimensional coordination polymer {[Cd(L)(H2O)(bpy)](ClO4)2(MeOH)0.5} n (3) with (A–B) n array and the discrete dumbbell-like complex [Cd2(L)2(tp)(H2O)2](tp)(H2O)9 (4) with (A–B–A) patterns.Self-assembly of the dipodal ligand L and CdX2 (X = ClO4 and NO3) produced unique pseudo-cyclic complexes (A) [Cd(L)(H2O)(CH3OH)](ClO4)2 (1) and [Cd(L)(H2O)(NO3)](NO3) (2), respectively. From the stepwise reaction of the pseudo-cyclic complexes (A) followed by coligands (B) such as 4,4′-bipyridine and terephthalate, the controlled one-dimensional coordination polymer {[Cd(L)(H2O)(bpy)](ClO4)2(MeOH)0.5} n (3) with (A–B) n array and the discrete “dumbbell”-like complex [Cd2(L)2(tp)(H2O)2](tp)(H2O)9 (4) with (A–B–A) patterns were isolated.
Keywords: Dipodal ligand; Cadmium(II) complex; Pseudo cyclic complex; 1-D coordination polymer; Dumbbell-like complex;

The hydrothermal reaction of CuCN and bix (bix = 1,4-bis(imidazole-l-ylmethyl)benzene) in the presence of 4,5-imidazoledicarboxylic acid and HCl in water leads to formation of the pale yellow crystals. The structure of this complex features a vase-shaped 3D network of {Cu(CN)} substructure constructed from the puckered layers containing large 34-membered Cu–CN–Cu rings.A new photoluminescent copper(I) cyanide polymer [(CuCN)4(bix)] n (bix = 1,4-bis(imidazole-l-ylmethyl)benzene) has been hydrothermally synthesized and structurally characterized. The structure of this complex features a vase-shaped 3D network of {Cu(CN)} substructure constructed from the puckered layers containing large 34-membered Cu–CN–Cu rings. The present compound was characterized using IR, Elemental analysis and X-ray single-crystal analysis. The photoluminescent property of the title compound was also investigated.
Keywords: Copper(I) polymer; Cyanide-bridging; Photoluminescent property; Flexible N-donor ligand; Bix ligand; Hydrothermal synthesis;

Crystal structure and surface photovoltage of a series of Ni(II) coordination supramolecular polymer by Li-Ping Sun; Shu-Yun Niu; Jing Jin; Guang-Di Yang; Ling Ye (679-682).
Three Ni(II) coordination supramolecular polymers were hydrothermal synthesized and characterized by crystallography and SPS technique. The three complexes exhibit positive SPV response in the range of 300–800 nm, and possess the characteristic of p-type semiconductor.Three Ni(II) coordination supramolecular polymer [Ni(pdc)(H2O)3] n (1), {[Ni(Imh)4(H2O)2] [Ni(btec)(H2O)2 (Imh)2] · H2O} n (2), [Ni(opha)(phen)(H2O)3] · H2O (3) were synthesized by hydrothermal method (H2pdc = pyridine-2,3-dicarboxylic acid, H4btec = 1,2,4,5-benzenetetracarboxylic acid, opha =  o-phthalic acid, phen = 1,10-phenanthroline, Imh = Imidazole). Complexes (1) and (2) possess 1D infinite coordination chain structure and the chains are separately further connected to 2D and 3D structure by hydrogen bonds. Complex (3) is a 1D coordination supramolecular compound via the connection of hydrogen bonds. The results of surface photovoltage spectrum (SPS) for complexes (1)–(3) indicate that three complexes exhibit positive surface photovoltage (SPV) response in the range of 300–800 nm, and possess the characteristic of p-type semiconductor.
Keywords: Ni(II); Coordination supramolecular polymer; Hydrogen bond; Crystal structure; Surface photovoltage;

Polymerized catalyst 5 has been synthesized and can be used as catalyst for the polymerization of ethylene in the presence of methylaluminoxane (MAO) as co-catalyst in very high activities.Metallocene complexes with an allyl group (η5-C3H5C5H4)(η5- t BuC5H4)ZrCl2 (2), (η5-C3H5C5H4)(η5- t BuC5H4)ZrCl2 (3) and (η5-C3H5C5H4)(η5- t Bu2C5H3)ZrCl2 (4) have been synthesized and characterized. The polymerized metallocene catalyst 5 is prepared by the copolymerization of 3 with styrene in the presence of radical initiator. In the presence of MAO, 25 can be used as catalysts for ethylene polymerization with high activities.
Keywords: Metallocene; Catalysts; Polymerized metallocene; Ethylene polymerization; X-ray structure analysis;

The first discrete tetranuclear complex containing 4-substituted triazole (m-phenol)-1,2,4-triazole (ptr) was obtained from the reaction of AgNO3 with ptr, which shows blue fluorescence feature with a broad emission at 432 nm excited at 363 nm, possibly originating from the π–π transition of the triazole ring.A novel triazole-bridging polynuclear silver(I) complex, [Ag4(ptr)6](NO3)4  · 4H2O (1), was synthesized with (m-phenol)-1,2,4-triazole (ptr), which is the first discrete tetranuclear complex containing 4-substituted triazoles. The compound features blue fluorescence with a broad emission at 432 nm excited at 363 nm, possibly originating from the π–π transition of the triazole ring.
Keywords: Silver(I); 1,2,4-Triazole; (m-Phenol)-1,2,4-triazole; Structure; Fluorescence;

Characterization of a novel water tape containing (H2O)18 clusters by Feng Li; Taohai Li; Daqiang Yuan; Jian Lv; Rong Cao (691-694).
A novel water tape containing (H2O)18 cluster units has been observed in the lattice of 1, in which each (H2O)18 cluster consists of one (H2O)12 and two (H2O)5 subunits.A novel water tape containing (H2O)18 cluster units has been observed in the lattice of 1, in which each (H2O)18 cluster consists of one (H2O)12 and two (H2O)5 subunits.
Keywords: Water cluster; Discrete; Polymeric; Morphology; Tape;

Synthesis, molecular structure and magnetic behaviour of Dy832-OR)6(μ,η2-OR)41-OR)8(μ,η1-OR)6 R = C2H4OPr i by Jérôme Le Bris; Liliane G. Hubert Pfalzgraf; Marc Rolland; Yann Garcia (695-698).
The reaction between dysprosium chips or Dy5O(OPr i )13 and 2-isopropoxyethanol afforded the title compound which was characterized in the solid state by X-ray diffraction and magnetic susceptibility measurements.The reaction between dysprosium chips or Dy5O(OPr i )13 and 2-isopropoxyethanol afforded the title compound. It has been characterized in the solid state by X-ray diffraction and magnetic susceptibility measurements.
Keywords: Dysprosium; Functional alkoxide; X-ray structure; Cluster; Magnetism;

A novel 1-D ferromagnetic compound based on manganese(II) and azide with formula [Mn5(bpd)51,1-N3)8(N3)2(H2O)2] · bpd · H2O (1) (bpd = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) was synthesized and structurally and magnetically characterized.A novel 1-D ferromagnetic compound based on manganese(II) and azide with formula [Mn5(μ 1,1-N3)8(N3)2(bpd)5 (H2O)2] · bpd · H2O (1) (bpd = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) was synthesized and structurally and magnetically characterized. Single-crystal X-ray diffraction shows that 1 consists of a one-dimensional convalent constructed by linear Mn 5 II subunits, in which each MII ion is coordinated in a distorted octahedral geometry. Magnetic measurements have been performed for the compound, showing a moderate ferromagnetic coupling.
Keywords: Manganese(II); 1,4-bis(4-Pyridyl)-2,3-diaza-1,3-butadiene; End-on azides; 1D coordination polymers; Magnetic behavior;

The ruthenium(III) bis-bidentate Schiff base complexes were synthesized and characterized and the present ruthenium complex system effectively catalyzes the transfer hydrogenation of imines to amines.The mono anionic bidentate Schiff base ligands of N, O bonding system has been employed to synthesize a series of new stable ruthenium(III) complexes of general composition [RuX(EPh3)(L)2] (where, E = P or As, X = Cl or Br and L = O, N donor of Schiff bases). All the complexes have been fully characterized by elemental analyses, magnetic susceptibility measurements, FT-IR, UV–Vis, EPR and cyclic voltammetric techniques. The catalytic reactivity explored proving these complexes to be efficient in the transfer hydrogenation of imines to amines with moderate to high conversions.
Keywords: N, O donors; Ru(III) bis-bidentate Schiff base complexes; Spectral studies; Transfer hydrogenation of imines;

The reaction of N-2-mercaptophenyl-2′pyridinecarboxamide (H2L) with bis(acetylacetonato)dioxomolybdenum(VI) ([MoO2(acac)2]) yielded, along with [MoO2L], the β-octamolybdate(VI) [Li(thf)3]2Na2[Mo8O26], linked via hepta-coordinated Na+ ions to two dinuclear, oxo- and acetato-bridged oxomolybdenum(V) units of composition {[Li(thf)2(ac)]2[(acac)MoVO(μ-O)2 (μ-ac)MoVO]}, and thus to a novel inorganic–organic hybrid system solely based on molybdenum.The reaction of [MoO2(acac)2] (acac = acetylacetonate) with the dilithium salt of N-(2-mercaptophenyl)-2′-picolinamide (H2N2S) in the presence of Na+ yielded the MoVI complex [MoO2(N2S)] · 2THF along with the β-octamolybdate [MoVI 8O26]4−, stabilised by two [Li(thf)3]+ linking to two terminal oxo groups of the cluster, and two Na+, each linking to four terminal oxo groups of octamolybdate and three acetato (ac) ligands of {[Li(thf)2(ac)]2[(acac)MoVO(μ-O)2(μ-ac)MoVO]} units, sandwiching the octamolybdate. Along with this structurally characterised cluster system, [MoO2(N2S)] was isolated. The preparation of the ligand H2N2S afforded a novel dithioacetal and urea derivative.
Keywords: Octamolybdate; Dinuclear oxomolybdenum; N2S-ligand; Lithium coordination; Sodium coordination;

Chiral discrimination in binuclear square planar metal complexes of group 10 by Oscar Picazo; Ibon Alkorta; José Elguero; Markku R. Sundberg (712-715).
Chiral discrimination in binuclear homo- and heterochiral complexes formed by hydrazine, a metal atom of group 10 (Ni, Pd, Pt) and halogen atoms (F, Cl, Br, I) depends on the electronic properties arising from the metal atoms and the ligand atoms attached to them.Chiral discrimination in binuclear homo- and heterochiral complexes formed by hydrazine, a metal atom of group 10 (Ni, Pd, Pt) and halogen atoms (F, Cl, Br, I) depends on the electronic properties arising from the metal atoms and the ligand atoms attached to them. The complexes were studied by quantum chemical methods by applying DFT methods at the B3LYP/LANL2DZ level of theory.
Keywords: DFT; Chiral discrimination; Hydrazine; Group 10 metals;

The first 1,3,2-diazaalumina-[3]ferrocenophanes by Bernd Wrackmeyer; Elena V. Klimkina; Wolfgang Milius (716-721).
N,N′Dilithio-1,1′-bis(trimethylsilylamino)ferrocene reacts with aluminum dichlorides RAlCl2 [R =  t Bu, CH(SiMe3)2, Si(SiMe3)2] in the presence of pyridine to give the respective 1,3,2-diazaalumina-[3]ferrocenophanes as pyridine adducts. The complex with R =  t Bu could be isolated in good yield and high purity and was characterised by multinuclear NMR in solution and X-ray structural analysis in the solid state.The dilithiated derivative 2 of 1,1′-bis(trimethylsilylamino)ferrocene (1) reacts with various aluminum dichlorides RAlCl2 [R =  t Bu (3a), CH(SiMe3)2 (3b), Si(SiMe3)2 (3d)] in the presence of pyridine to give the respective 1,3,2-diazaalumina-[3]ferrocenophanes 4a,b,d as pyridine adducts, of which 4a could be isolated in good yield and high purity. The aluminum halide (Me3Si)3CAlCl2 in THF did not react with 2. The molecular structure of 4a, determined by X-ray analysis, shows the tert-butyl group in trans-position relative to the N–Si bond vectors. NMR spectra prove that prominent structural features are retained in solution, including restricted rotation about the Al–N(py) bond, shown by low-temperature NMR spectra.
Keywords: Aluminum amides; 1,1′-Bis(trimethylsilylamino)ferrocene; [3]Ferrocenophanes; NMR; X-ray;

Antitumor active monofunctional platinum(II) complexes: Synthesis, structural characterization and reactivity towards biomolecules by Xinliu Gao; Xiaoyong Wang; Jian Ding; Liping Lin; Yizhi Li; Zijian Guo (722-726).
The platinum(II) complexes of l-valine-N-8-quinolylamide and l-leucine-N-8-quinolylamide were shown to bind to DNA with high affinity and demonstrated comparable cytotoxicity to cisplatin against the murine leukemia cell line (P-388) and the human non-small-cell lung cancer cell line (A-549).Monofunctional platinum(II) complexes represent a class of antitumor agents that do not obey the classical structure–activity relationships. We report herein two novel platinum(II) complexes [PtL1Cl] (L1  =  l-valine-N-8-quinolylamide) and [PtL2Cl] (L2  =  l-leucine-N-8-quinolylamide) in which Cl acts as the only potential leaving group. These complexes showed comparable cytotoxicity to cisplatin against the murine leukemia cell line (P-388) and the human non-small-cell lung cancer cell line (A-549), and could potentially form monofunctional adducts with DNA.
Keywords: Platinum; Antitumor agents; Drug design; Structure–activity relationship; Medicinal chemistry;

Two novel heteropolytungstates K[M(phen)2(H2O)]2[PW12O40] · 2H2O (M=Fe 1, Cu 2, phen = 1,10′-phenanthroline) have been hydrothermally prepared, in which bisupporting Keggin units are joined, for the first time, by potassium cations into unprecedented one-dimensional chains.▪Two novel heteropolytungstates K[M(phen)2(H2O)]2[PW12O40] · 2H2O (M = Fe 1, Cu 2, phen = 1,10′-phenanthroline)have been synthesized and characterized by IR and single crystal X-ray diffraction. The two compounds are isomorphous and crystallized in the space group P 1 ¯ . They exhibit interesting 1D chainlike architectures assembled by potassium ions bridged bisupporting Keggin units. To our knowledge, it is the first time that supported polyoxoanions are linked by alkali metals into extended structures.
Keywords: Transition metal; Keggin unit; Potassium ions; One-dimensional chain;

The first example of Re(IV)-mediated nitrile–hydroxylamine coupling by Konstantin V. Luzyanin; Vadim Yu. Kukushkin; Matti Haukka; Armando J.L. Pombeiro (732-735).
The metal-mediated coupling between the acetonitriles in cis-[ReIVCl4(MeCN)2] and the N,N-dibenzylhydroxylamines R 2 3 NOH (R3  = CH2Ph, CH2C6H4C1-p) proceeds smoothly in CH2Cl2/MeCN at 20–25 °C for ca. 15 min to accomplish new imino species cis - [ ReCl 4 { NH=C ( Me ) ONR 2 3 } 2 ] (R3  = CH2Ph, 1, CH2C6H4C1-p, 2) in ca. 70% yield. The structures of the isolated compounds were based on elemental analyses (C, H, N), IR, FAB+-MS and on X-ray data for 1.The metal-mediated coupling between the acetonitriles in cis-[ReIVCl4(MeCN)2] and the N,N-dibenzylhydroxylamines R 2 3 NOH (R3  = CH2Ph, CH2C6H4C1-p) proceeds smoothly in CH2Cl2/MeCN at 20–25 °C for ca. 15 min to accomplish new imino species cis - [ ReCl 4 { NH=C ( Me ) ONR 2 3 } 2 ] (R3  = CH2Ph, 1, CH2C6H4C1-p, 2) in ca. 70% yield. The structures of the isolated compounds were based on elemental analyses (C, H, N), IR, FAB+-MS and on X-ray data for 1.
Keywords: Nitriles; Rhenium(IV) complexes; Nucleophilic addition; Metal-mediated reactions; Dibenzylhydroxylamines; Imino complexes;

Hydrogenated Schiff base ligands: Towards the controlled organisation of open metal frameworks by John Reglinski; Michelle K. Taylor; Alan R. Kennedy (736-739).
The synthesis and structures of bis-((μ2-acetato-O,O′)-μ-(N,N′-bis-(o-hydroxybenzyl)-1,3-diaminopropane)-(aquo)nickel)nickel, bis-((μ2-acetato-O,O′)-μ-(N,N′-bis-(o-hydroxybenzyl)-1,4-diaminobutane nickel)nickel acetate) and bis-((μ2-acetato-O,O′)-μ-(N,N′-bis(o-hydroxybenzyl)-1,4-diaminobutane)-(dimethylformamido)nickel)nickel are reported. These compounds are designed to draw attention to the wider structural catalogue available to symmetrical hydrogenated Schiff base complexes which contain a tetramethylene backbone.The synthesis and structures of bis-((μ2-acetato-O,O′)-μ-(N,N′-bis-(o-hydroxybenzyl)-1,3-diaminopropane)-(aquo)nickel)nickel, bis-((μ2-acetato-O,O′)-μ-(N,N′-bis-(o-hydroxybenzyl)-1,4-diaminobutane nickel)nickel acetate) and bis-((μ2-acetato-O,O′)-μ-(N,N′-bis(o-hydroxybenzyl)-1,4-diaminobutane)-(dimethylformamido)nickel)nickel are reported. These compounds are designed to draw attention to the wider structural catalogue available to symmetrical hydrogenated Schiff base complexes which contain a tetramethylene backbone.
Keywords: Tetradentate; Schiff base; Nickel; Butane-diamine;

A new one-dimensional copper–molybdenum bimetallic compound [Cu(2-PBIM)MoO4] (1) (2-PBIM = 2-(2-pyridyl)benzimidazole) containing left-handed and right-handed helical chains, which are built up from copper–molybdenum bimetallic oxide building block and further interconnected to form the double helical chains through μ2-O. The double helical chains are integrated via hydrogen bonding to form a 3D framework with channels in it.A new one-dimensional copper–molybdenum bimetallic compound [Cu(2-PBIM)MoO4] (1) (2-PBIM = 2-(2-pyridyl)benzimidazole) has been hydrothermally synthesized. X-ray structure analysis has revealed that compound 1 contains left-handed and right-handed helical chains, which are built up from copper–molybdenum bimetallic oxide building block and further interconnected to form the ladder-shaped chains through μ2-O. The ladder-shaped chains are integrated via hydrogen bonding to form a 3D framework with channels in it.
Keywords: 2-(2-pyridyl)benzimidazole; One-dimensional structure; Hydrothermal synthesis; Hydrogen bonding;

The 1 is a novel 2-D cadmium (II) metal-organic framework [Cd(μ4-NIPH)(μ2-OH2)] n constructed from polynuclear cadmium chains and bridge NIPH ligands.A cadmium metal-organic framework [Cd(μ4-NIPH)(μ2-OH2)] n (1) has been prepared by reaction of H2NIPH (H2NIPH = 5-nitroisophthalic acid) with Cd (II) under hydrothermal condition and characterized by single-crystal X-ray diffraction and TGA analysis. Single crystal X-ray diffraction analysis indicated that 1 is a 2-D layer structure constructed from polynuclear cadmium chains and bridge NIPH ligands. Furthermore, the layers are connected into 3-D supramolecular network through hydrogen bonds. The framework 1 exhibits photoluminescence at room temperature.
Keywords: Metal-organic framework; Crystal structure; Hydrogen bonding; Photoluminescence;

The first trinuclear transition metal tris(mercaptoimidazolyl)borate complexes, the gold(I) derivatives [Au3(Tm tBu)2]X (X = Cl, BF4, PF6, SbF6) have been prepared and fully characterized, including the X-ray structure of the hexafluoroantimonate salt.The first trinuclear transition metal tris(mercaptoimidazolyl)borate complexes, the gold(I) derivatives [Au3(Tm tBu)2]X (X = Cl, BF4, PF6, SbF6) have been prepared and fully characterized using a combination of analytical and spectroscopic techniques. The X-ray structure of the hexafluoroantimonate salt confirmed the presence of a novel cationic complex [Au3(Tm tBu)2]+ in which a triangular array of three gold atoms is coordinated simultaneously by two Tm tBu ligands. The three gold centers exhibit roughly linear coordination and the intermetallic distances suggest the presence of weak aurophilic interactions between them.
Keywords: Gold; Tris(mercaptoimidazolyl)borates; Soft scorpionates; Trinuclear complexes; Aurophilic interactions;

Macrocyclic ligand design: The interaction of selected transition and post-transition metal ions with a 14-membered N2S2-donor macrocycle by Jy D. Chartres; Murray S. Davies; Leonard F. Lindoy; George V. Meehan; Gang Wei (751-754).
Macrocycle 1,7-dithia-4,11-diazacyclotetradecane yields 1:1 complexes with Ni(II), Cu(II) and Ag(I) and shows a binding preference for Cu(II) and Ag(I) over Co(II), Zn(II), Cd(II) and Pb(II). The nickel complex is monomeric and 6-coordinate while the silver species is polymeric with a ‘stacked’ columnar arrangement; each silver ion adopts a distorted square pyramidal geometry.Interaction of 1,7-dithia-4,11-diazacyclotetradecane (1) with nickel(II), copper(II) and silver(I) yields the complexes [NiL(H2O)(CH3CN)](ClO4)2, [CuL](ClO4)2 and [AgL] n (ClO4) n (L =  1). The log  K values for the 1:1 complexes of cobalt(II), copper(II), zinc(II), cadmium(II), silver(I) and lead(II) in 95% MeOH are reported, with the strongest complexes occurring for copper(II) and silver(I). The X-ray structure of the nickel complex shows the four donors of the macrocycle coordinated around cis positions of an octahedron, with water and acetonitrile ligands occupying the remaining cis positions (the latter are trans to the amine donors and the sulfurs occupy trans axial positions). The silver complex is distorted square pyramidal with all macrocyclic donors bound; each sulfur bridges to an adjacent silver centre such that the latter attains a S3N2 environment and a cationic zig-zag polymeric arrangement is generated.
Keywords: S2N2-donor macrocycle; Nickel(II); Copper(II); Silver(I); Stability constants; X-ray;

The heterodimetallic complex Pd(μ-OOCMe)4Co(NCMe) is attacked by 1,10-phenanthroline (Phen) on cobalt(II) rather than palladium(II) atom to produce a tribridged binuclear complex Pd(μ-OOCMe)3(OOCMe)Co(Phen) in which the general shape of the PdCo moiety changes only slightly compared to the original tetrabridged structure.The heterodimetallic lantern complex Pd(μ-OOCMe)4Co(NCMe) is attacked by 1,10-phenanthroline (Phen) on cobalt(II) rather than palladium(II) atom to produce a tribridged binuclear complex Pd(μ-OOCMe)3(OOCMe)Co(Phen) in which the general shape of the PdCo moiety changes only slightly compared to the original tetrabridged structure.
Keywords: Palladium; Cobalt; Heterodimetallic complex; 1,10-Phenanthroline; Coordination;

Synthesis, crystal structure and bioactivity of a novel 18-metallacrown-6 [Mn6(H2O)6(abshz)6] · 36H2O by Longfei Jin; Fengping Xiao; Gongzhen Cheng; Zhenping Ji (758-760).
A novel macrocyclic hexanuclear manganese(III) 18-metallacrown-6 compound, [Mn6(H2O)6 (abshz)6] · 36H2O, has been prepared using a trianionic pentadentate ligand N-acetyl-5-bromosalicylhydrazide (abshz3−) and characterized by X-ray diffraction. Antibacterial screening data showed that the manganese metallacrown has strong antimicrobial activity against Staphylococcus aureus, Escherichia coli and Bacillus subtilis.A novel 18-metallacrown-6 compound, [Mn6(H2O)6 (abshz)6] · 36H2O (abshz =  N-acetyl-5-bromosalicylhydrazide), has been prepared and characterized. The crystal structure contains a neutral 18-membered metallacrown ring which is formed by the succession of six structural moieties of the type [Mn(III)–N–N]. Due to the meridional coordination, the ligand enforces the stereochemistry of the Mn3+ ions as a propeller configuration with alternating Λ/Δ forms. Antibacterial screening data showed that the complex has strong antimicrobial activity against Staphylococcus aureus, Escherichia coli and Bacillus subtilis.
Keywords: Metallacrown; Manganese complexes; Crystal structures; Bioactivity;

Direct syntheses and complete characterization of halide-free tetrakis(dialkylamino)silanes by Chiranjib Banerjee; Casey R. Wade; Axel Soulet; Gregory Jursich; James McAndrew; John A. Belot (761-763).
Efficient syntheses of tetrakis(dimethylamino)silane, tetrakis(methylethylamino)silane, and tetrakis(diethylamino)silane yield analytically pure compounds as halide-free species whose volatility systematically decreases with the addition of each ethyl group.Tetrakis(dialkylamino)silanes of the general formula Si(NRR′)4 (R = R′ CH3, CH2CH3, or R ≠ R′ = CH3 and CH2CH3) were prepared as halide-free, analytically pure compounds whose volatility scales with alkyl group size. The successful syntheses relied on the heavier silicon halides, SiBr4, and SiI4. In the case of SiBr4 incomplete amination with amines bulkier than dimethylamine ultimately led exclusively to BrSi(NR2)3, whereas SiI4 starting material afforded only homoleptic Si(NR2)4 whose complete characterization is presented. The tetrakis(dialkylamino)silanes failed to react with alcohols, even at elevated temperatures, and only slowly hydrolyze.
Keywords: Silicon; Amine; Precursor; Volatile; Halide;

Bridge splitting of trans-[PtCl2(C2H4)]2 by C2H4 in chloroform yields trans-[PtCl2(C2H4)2] which slowly isomerises to cis-[PtCl2(C2H4)2] (crystal structure reported); the bridge-splitting equilibrium constant was determined by the use of a combined NMR tube/spectrophotometric cell, enabling NMR and UV/vis measurements on the same closed system.Bridge splitting of trans-[PtCl2(C2H4)]2 by C2H4 in chloroform yields trans-[PtCl2(C2H4)2] which slowly isomerises to cis-[PtCl2(C2H4)2] (crystal structure reported); the bridge-splitting equilibrium constant was determined as 6.8 ± 0.6 mol−1  dm3 by the use of a combined NMR tube/spectrophotometric cell, enabling NMR and UV/vis measurements on the same closed system.
Keywords: Ethene; Platinum; Bridge-splitting; Combined UV/vis NMR;

Two silver(I) complexes, [Ag2(HL)2] · [Mg(H2O)6] (H3L = 5-sulfo-salicylic acid) 1 and Ag4Sr2(HL)(H2O)14  · 2H2O 2, have been synthesized and templated by alkaline-earth metals (Mg2+ and Sr2+, respectively). X-ray crystallography reveals that compound 1 is a 1-D chain polymer and 2 is a 2-D framework constructed from unusual tetramer units of [Ag2(HL)2] dimers. The fluorescent emission spectra of the two complexes are also described.Two silver(I) complexes, [Mg(H2O)6][Ag2(HL)2] (1) and Sr2Ag4(HL)(H2O)14  · 2H2O (2) (H3L = 5-sulfo-salicylic acid), have been synthesized by use of alkaline-earth metals (Mg2+ and Sr2+, respectively) as templates. Single-crystal X-ray diffractions reveal that compound 1 is a 1-D chain polymer built from [Ag2(HL)2] dimers and compound 2 is a 2-D framework constructed from unusual tetramer units of [Ag2(HL)2] dimers. The two complexes are both further linked into 3-D networks by the extensive intermolecular hydrogen bonding interactions.
Keywords: Alkaline-earth metals; Silver complexes; Template synthesis; Tetramer;