Polysulfonylamines. CXX. Bis(tetrahydrothiophene‐S)gold(I) benzene‐1,2‐disulfonimidate

Both ions of the title compound, [Au(C₄H₈S)₂](C₆H₄NO₄S₂), display crystallographic twofold symmetry. The Au atom exhibits linear coordination, with Au—S = 2.2948 (14) Å and S—Au—S = 178.47 (9)°. The crystal packing consists of layers of anions connected by C—H?O hydrogen bonds; the cations occupy cavities in these layers and the ions are linked by Au?N contacts of 3.009 (7) Å. Further C—H?O interactions connect the layers.     

Bis(tetra‐n‐butylammonium) (a redetermination at 150 K) and bis(tetraphenylarsonium) bis(1,3‐dithiole‐2‐thione‐4,5‐dithiolato)zinc(II) (at 300 K)

The title compounds are salts of the general form (Q⁺)₂[Zn(dmit)₂]^2?, where dmit corresponds to the ligand (C₃S₅)^? present in both and Q⁺ to the counter‐cations (ⁿBu₄N)⁺ [or C₁₆H₃₆N⁺] and (Ph₄As)⁺ [or C₂₄H₂₀As⁺], respectively. In the first case, Zn is in the 4e special positions of space group C2/c and hence the [Zn(dmit)₂]^2? dianion possesses twofold axial crystallographic symmetry. Including these, there are now 11 known examples of [Zn(dmit)₂]^2? or its analogues, with O replacing the exocyclic thione S, and [Zn(dmio)₂]^2? dianions in nine structures with various Q. Comparison of these reveals a remarkable variation in details of the conformation which the dianion may adopt in terms of Zn coordination, equivalence of the Zn—S bond lengths, displacement of Zn from the plane of the ligand and overall dianion shape.     

Diiodobis(4‐methylpentan‐2‐onato‐C4,O)tin(IV): a comparison with diiodobis(3‐methoxy‐3‐oxopropyl‐C,O)tin(IV)

The title compound, [SnI₂(C₆H₁₁O)₂], contains a six‐coordinate tin centre as a consequence of intramolecular Sn—O interactions. The Sn—O bond lengths range between 2.428 (4) and 2.439 (4) Å.     

trans‐Cyano(6‐methyl‐1,4,8,11‐tetraazacyclotetradecan‐6‐amine)cobalt(III) bis(perchlorate) hydrate and trans‐hydroxo(6‐methyl‐1,4,8,11‐tetraazacyclotetradecan‐6‐amine)cobalt(III) bis(perchlorate)

The crystal structures of a pair of closely related macrocyclic cyano‐ and hydroxopenta­amine­cobalt(III) complexes, as their perchlorate salts, are reported. Although the two complexes, [Co(CN)(C₁₁H₂₇N₅)](ClO₄)₂·H₂O and [Co(OH)(C₁₁H₂₇N₅)](ClO₄)₂, exhibit similar conformations, significant differences in the Co—N bond lengths arise from the influence of the sixth ligand (cyano as opposed to hydroxo). The ensuing hydrogen‐bonding patterns are also distinctly different. Disorder in the perchlorate anions was clearly resolved and this was rationalized on the basis of distinct hydrogen‐bonding motifs involving the anion O atoms and the N—H and O—H donors.     

trans‐Bis(thioacetato‐S)bis(triphenylphosphine‐P)nickel(II)

In the title compound, [Ni(C₂H₃OS)₂(C₁₈H₁₅P)₂], the Ni atom lies on an inversion centre and the tri­phenyl phosphine and thio­acetate ligands are bonded to the central Ni^II atom in a trans fashion, with Ni—S = 2.2020 (8) and Ni—P = 2.2528 (8) Å, and angle S—Ni—P = 92.47 (3)°.     

Synthesis and characterization of a poly(GMA)‐graft‐poly(Z‐L‐lysine) graft copolymer with a rod‐like structure

This study applied the macromonomers and glycidyl methacrylate (GMA) to synthesize a series of the graft copolymers, poly(GMA)‐graft‐poly(Z‐L ‐lysine), and investigated the conformation of the graft copolymer. The graft copolymers were synthesized with different GMA monomer ratios (28 to 89%) and different degrees of polymerization (DP) (8 to 15) of the poly(Z‐L ‐lysine) side chain to analyze secondary structure relationships. Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and both wide angle and small angle X‐ray scattering spectroscopy (WAXS, SAXS) were used to investigate the relationship between the microstructure and conformation of the graft copolymers and the different monomer ratios and side chain DP. In AFM images, n8‐G89 (the graft copolymer containing 89% GMA units and the macromonomer DP is 8) showed tiny and uniform rod‐like structures, and n14‐G43 (the graft copolymer containing 43% GMA units and the macromonomer DP is 14) showed uniform rod‐like structures. FTIR spectra of the graft copolymers showed that the variations of α‐helix and β‐sheet secondary structures in the graft copolymers relate to the monomer ratios of the graft copolymers. However, the X‐ray scattering patterns indicated that the graft copolymer conformations were mainly dependent on the poly(Z‐L ‐lysine) side chain length, and these results were completely in accordance with the AFM images. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4655–4669, 2009     

Insertion von Rhodizonsäure in die Gallium‐Gallium‐ bzw. Indium‐Indium‐Bindungen von Digallan(4)‐ bzw. Diindan(4)‐Verbindungen

Insertion of Rhodizonic Acid into the Gallium‐Gallium and Indium‐Indium Bonds of Digallane(4) and Diindane(4) Compounds Rhodizonic acid (C₆O₆H₂, 5, 6‐dihydroxy‐5‐cyclohexene‐1, 2, 3, 4‐tetraone) did not react with tetrakis[bis(trimethylsilyl)methyl] digallane(4) ( 1 ) and the corresponding diindium compound ( 2 ) by the transfer of protons. Instead the acid was completely inserted into the element‐element bonds of the starting compounds and the gallium or indium atoms were oxidized from the oxidation state of +II to +III. In contrast to the free acid, the OH groups of the products are not attached to neighbouring carbon atoms, but occupy the 1, 4‐positions of the central six‐membered rings. Both dialkylgallium and dialkylindium groups of the products ( 3 (Ga) and 4 (In)) are coordinated by two oxygen atoms. They adopt opposite positions at the C₆O₆ molecular core.     

Development of Pr(III) Selective Electrode Using 1,6,7,12‐Tetramine‐2,5,8,11‐tetraoxo‐1(12),6(7)‐di(biphenyl)‐dodecane (TATODBDD) as a Neutral Carrier

A polyvinyl chloride (PVC) membrane based Pr(III) selective electrode was constructed using 1,6,7,12‐tetramine‐2,5,8,11‐tetraoxo‐1(12),6(7)‐di(biphenyl)dodecane (TATODBDD) as a neutral carrier. The sensor exhibits a Nernstian response for Pr(III) ions, a wide concentration range of 3.9×10^?7?1.0×10^?1 mol/L with a detection limit of 5.0×10^?8 mol/L and slope of 19.5 mV/decade. The developed sensor revealed relatively good selectivity and high sensitivity for Pr(III) ions over the other lanthanide ions. The potentiometric response of the sensor is independent in the pH range 2.9–9.5. The advantages of sensor are low resistance, very fast response time (<10 s) with good selectivity. This sensor can be used up to 6 weeks without any divergences in potential response.     

Synthesis by ATRP of poly(ethylene‐co‐butylene)‐block‐polystyrene,poly(ethylene‐co‐butylene)‐block‐poly(4‐acetoxystyrene) and its hydrolysis product poly(ethylene‐co‐butylene)‐block‐poly(hydroxystyrene)

Diblock copolymers of poly(ethylene‐co‐butylene) and polystyrene or poly(4‐acetoxystyrene) are synthesized by atom transfer radical polymerization (ATRP) using a 2‐bromopropionic ester macroinitiator prepared from commercial monohydroxyl functional narrow dispersity hydrogenated polybutadiene (Kraton Liquid Polymer, L‐1203). ATRP carried out in bulk and in xylene solution with cuprous bromide and two different complexing agents 2,2′‐bipyridine (bipy) and 1,1,4,7,10,10‐hexamethyltriethylenetetraamine (HMTETA) yielded well‐defined diblock copolymers with polydispersities around 1,3. The diblock copolymer with poly(4‐acetoxystyrene) was hydrolyzed to the corresponding poly(4‐hydroxystyrene) sequence.