bluuebunny/crossref_metadata_2025 huggingface dataset:
Bindung von Metall-Ionen an Dipeptide: Struktur von Thallium(I)-(3-benzyl-6-carboxylatomethyl-2,5-diketopiperazin) / Binding of Metal Ions by Dipeptides: Structure of Thallium(I) 3-Benzyl-6-carboxylatomethyl-2,5-diketopiperazine
Authors: Mikulcik P. , Bissinger P. , Riede J. , Schmidbaur H.
Published: March 2015

Ester cleavage of aspartame (L-α-aspartyl-L-phenylalanine methylester) (1), by equimolar quantities of thallium ethoxide is accompanied by intramolecular cyclisation to give thallium 3-benzyl-6-(carboxylatomethyl)-2,5-dioxopiperazine (2). The solid state structure of the crystalline product was determined by single-crystal X-ray diffraction analysis. The cations were found to form four short and four elongated contacts to seven oxygen atoms and one nitrogen atom of a total of six neighbouring 3-benzyl-6-(carboxylatomethyl)-2,5-dioxopiperazine anions. There are inter-anionic hydrogen bonds only between the imino groups and the carbonyl oxygen atoms (O3, O4), featuring a pattern similar to that found for cytosine-guanosine contacts in DNA.
Zinkkomplexe kettenförmiger N3-Chelatliganden / Zinc Complexes of Chain-Like N3 Chelate Ligands
Authors: Wirbser Joachim , Vahrenkamp Heinrich
Published: March 2015

The title ligands bis[(2-pyridyl)methyl]amine (BPA) and bis[(2-benzimidazolyl)methyl]-methylamine (BBMA) were used to prepare complexes with zinc salts. 1:1 complexes of BPA with ZnCl2, ZnBr2, ZnI2, Zn(SCN)2, Zn(CH3COO)2, and Zn(NO3)2 as well as of BBMA with ZnCl2, ZnBr2, and Zn(NO3)2 were obtained. Spectroscopic evidence indicates that all these complexes are five-coordinate molecular LZnX2 units. With Zn(ClO4)2, BPA forms a 2:1 complex presumed to be an octahedral ionic L2ZnX2 species. The crystal structures of BPA · ZnCl2 and BBMA · ZnBr2 reveal distorted square pyramidal resp. trigonal bipyramidal molecular geometries.
Bicyclo[2.2.2]octane-2-spirocyclohexanes, Part 5 [1] The Action of Grignard Reagents on Spirodiisophora-3′,6-dione
Authors: Kurzer Frederick , Hawkes Jane E.
Published: March 2015

Grignard reagents react with spirodiisophora-3′,6-dione exclusively at its 3′-keto-function, yielding 3′-eq-alkyl(or phenyl)-3′-ax-hydroxyspirodiisophor-6-ones. Successive dehydration and monobromination of the methyl homologue yields products, the structural details of which are settled by their 13C NMR spectra.
Pyrylium Salts with Long Alkyl Substituents, II 2,4-Dimethyl-6-undecylpyrylium Perchlorate and Derived Pyridinium Salts
Authors: Bogatian Mariana , Deleanu Calin , Mihai Gheorghe , Balaban Teodor Silviu
Published: March 2015

The crystalline title pyrylium salt was obtained by SnCl4 catalysed acylation of mesityl oxide with lauroyl chloride followed by treatment with perchloric acid and column chromatography. This new pyrylium salt was converted in high yields into the corresponding pyridine and N-substituted pyridinium salts (N-methyl, N-phenyl, N-(4-n-butylphenyl), and N-dodecyl) whose proton (300 MHz) and carbon-13 (75 MHz) NMR spectra are presented.
On the Chemistry of Ingenol, Va. Preparation of Tritium-Labeled 3-O-Tetradecanoylingenol ([20-3Η]-3-TI)
Authors: Roeser H. , Sorg B. , Hecker E.
Published: March 2015

Tritium-labeling of the ingenol monoester 3-O-tetradecanoylingenol (3-TI), the prototype tumor promoter of the ingenane type diterpene esters, is described. The preparation starts with oxidation of 3-TI by manganese dioxide to yield 3-TI-20-aldehyde which is reduced by [3H]-sodium borohydride in the presence of equimolar amounts of cerium trichloride hexahydrate to give [20-3H]-3-TI. The labeled promoter is obtained in 42% overall yield with a specific radioactivity of 15.8 Ci/mmol.
Direct Electrochemical Synthesis of Pyrimidine-2-thionato Complexes of Zinc(II) and Cadmium(II): The Crystal Structure of (1,10-Phenanthroline)bis(pyrimidine-2-thionato)cadmium(II)
Authors: Castro R. , Durán M. L. , García-Vázquez J. A. , Romero J. , Sousa A. , Castiñeiras A. , Hiller W. , Strähle J.
Published: March 2015

Zn(pymt)2 and Cd(pymt)2 complexes have been obtained by electrochemical oxidation of anodic zinc or cadmium in acetonitrile solutions of pyrimidine-2-thione (Hpymt). When 2,2′-bipyridine (bipy) or 1,10-phenanthroline (phen) was added to the electrochemical cell, the adducts [M(pymt)2(bipy)], or [M(pymt)2(phen)] (M = Zn or Cd) were obtained. Crystals of [Cd(pymt)2phen] are orthorhombic, with a = 9.882(2), b = 12.491(1), c = 16.513(2)Å, space group P212121 and Z = 4. The cadmium atom has distorted octahedral geometry, and one nitrogen atom of each pyrimidine-2-thiolato ligand is not coordinated.
Hydrogen Bonding in Acid Li-, Ni-, Tetrabutylammonium, and Ammonium Salts of Benzene-1,2,4,5-tetracarboxylic Acid (Pyromellitic Acid)
Authors: Jessen Sven M. , Küppers Horst , Luehrs Dean C.
Published: March 2015

Four acid salts of pyromellitic acid (benzene-1,2,4,5-tetracarboxylic acid) have been synthesized and studied by X-ray diffraction and IR spectroscopy. (1) Dilithium dihydrogen pyromellitate pentahydrate, Li2[C6H2(COO)4H2]· 5H2O; monoclinic, P21/m, a = 6.214(2), b = 19.647(7), c = 6.592(2)Å, β = 115.90(2)°, Ζ = 2, R = 0.068, Rw = 0.067. (2) Hexaaquanickel dihydrogen pyromellitate, [Ni(H2O)6][C6H2(COO)4H2]; monoclinic, P2/m, a = 6.528(1), b = 9.927(2), c = 6.472(1)Å, β = 115.57(1)°, Z = 1, R = 0.044, Rw = 0.039. (3) Tetrabutylammonium trihydrogen pyromellitate, [(C4H9)4N][C6H2(COO)4H3]; monoclinic, P21/c, a = 9.719(4), b = 18.823(8), c = 15.795(5)Å, β = 107.42(3)°, Z = 4, R = 0.059, Rw = 0.039. (4) Diammonium dihydrogen pyromellitate, [NH4]2[C6H2(COO)4H2]; monoclinic, P21/c, a = 4.7665(6), b = 11.681(3), c = 10.149(2)Å, ß = 102.19(2)°, Z = 2, R = 0.045, Rw = 0.039. Compounds 1, 2, and 3 show very short intramolecular hydrogen bonds between adjacent carboxylic groups (O ••• O distances 2.384(6), 2.386(5), 2.387(3)Å, respectively). Compound 4 forms intermolecular hydrogen bonds (O ··· O distance 2.642(2) A). The different hydrogen bonding modes are also evident in the IR spectra.
Synthesis, Characterization and Crystal Structure of Bis(benzoyl-thiobenzoyl-methanato-O,S)diphenyl Lead
Authors: Singh Kh. Ajit , Gupta Vishnu D. , Linti Gerald , Nöth Heinrich
Published: March 2015

Bis(benzoyl-thiobenzoyl-methanato-O,S)diphenyl lead has been synthesized and characterized by IR and NMR spectra. Its crystal and molecular structure reveals that the lead atom possesses a skew-trapezoidal bipyramidal environment with pairs of the same donor atoms (O and S) in the cis position, and the two phenyl groups settled with a C–Sn–C bond angle of 138.4(2)°. The Pb–O bonds are longer than the Pb–S bonds revealing the anisobidentate nature of this ligand.
Synthese eines Thymosin β10-Fragments zur Entwicklung spezifischer Antikörper / Synthesis of a Fragment of Thymosin β10 for the Development of Specific Antibodies
Authors: Hörger Susanne , Gallert Brigitte , Echner Hartmut , Voelter Wolfgang
Published: March 2015

The N-terminal fragment 1-12 of thymosin β10 was synthesized by the solid phase method using p-benzyloxybenzyl alcohol/polystyrene/divinylbenzeneresin and N-a-Fmoc amino acids with tert-butyl or Boc side chain protecting groups. Coupling was performed with BOP. The peptide was purified by preparative HPLC.
A Simple Model for the Enzyme-Substrate-Complex of the Quercetinase Reaction. Crystal Structure of Flavonolatocobalt(III)(salen)
Authors: Hiller Wolfgang , Nishinaga Akira , Rieker Anton
Published: March 2015

Flavonolatocobalt(III)(salen), a model enzyme-substrate-complex for the quercetinase reaction, was synthesized and its crystal structure determined. C31H23CoN2O5 · 2 CH2Cl2, M = 732.35, triclinic, space group P 1̅ , a = 12.463(2), b = 13.270(2), c = 10.041(2) Å, α = 97.89(1)°, β= 108.08(1)°, γ= 83.56(1)°, U = 1559.4 Å3, Z = 2.
Calcium-bis { [tris(trimethylsilyl)silyl]tellanid } · 4 THF-Synthese, spektroskopische Charakterisierung und Struktur / Calcium-bis{[tris(trimethylsilyl)silyl]tellanide} · 4THF-Synthesis, Spectroscopic Characterization and Structure
Authors: Becker Gerd , Klinkhammer Karl Wilhelm , Schwarz Wolfgang , Westerhausen Matthias , Hildenbrand Thomas
Published: March 2015

Calcium bis{[tris(trimethylsilyl)silyl]tellanide} · 4THF is obtained by metallation of [tris(trimethylsilyl)silyl]tellane using dimeric calcium bis[bis(trimethylsilyl)amide] in toluene, followed by recrystallisation from tetrahydrofuran. The compound is characterized by a remarkable highfield shift of the 125Te{1H}-NMR resonance (-2204 ppm vs. Me2Te). The X-ray structure determination (triclinic, P1; Z = 1; a = 1042.6(2), b = 995.7(2), c = 1379.6(3) pm; α = 90.06(2), β = 92.76(2), γ = 94,03(2)° at -100 °C) shows a distorted octahedral coordination sphere of the calcium atom (Ca-Te 319; Ca-O 236 and 241 pm). The two [tris(trimethylsilyl)silyl]-tellanide ligands are in a trans position; the angle Ca-Te-Si is widened to 129°.
Komplexe 17-gliedriger Dibenzo-Makrocyclen mit N3O2- bzw. N3S2-Donorzentren Strukturen von [Zn(′N3O2′)Cl]2ZnCl4 und [Hg(′N3S2′)Br2] / Complexes of 17-Membered Dibenzo Macrocycles with N3O2 or N3S2 Donor Sets Crystal and Molecular Structures of [Zn(′N3O2′)Cl]2ZnCl4 and [Hg(′N3S2′)Br2]
Authors: Kallert Uwe , Mattes Rainer
Published: March 2015

The macrocyclic complexes [Zn(′N3O2')Cl]2ZnCl4 (1) und [Hg(′N3S2')Br2] (2) have been prepared and their crystal structures determined. Zn(II) is incorporated into the macrocyclic cavity of the ′N3O2′ ligand and primarly coordinated to the three nitrogen donors of the macrocycle and to a chloride ion. Weaker interactions occur with the oxygen donors of the macrocycle. The Zn—O distances are 296,4(5) and 322,4(6) pm. In complex 2 Hg(II) lies outside the macrocyclic cavity. The donor set comprises two secondary amine nitrogen atoms and a thioether sulfur atom of the macrocycle, and two bromide anions. The coordination polyhedron can be described as a trigonal bipyramid. The conformational behaviour of the ′N3O2′ and the ′N3S2′ ligands within these and other complexes is discussed. ′N3O2′ and ′N3S2′ are 17-membered dibenzo macrocycles. Crystal data for [Zn(′N3O2')Cl]2ZnCl4 (1): monoclinic, space group C2/c, a = 2864(4), b = 951.0(2), c = 1986(4) pm, β = 118.5(1)°, Z = 4, 2499 reflections, R = 0.0581; [Hg(′N3S2′)Br2] (2): monoclinic, space group P21/c, a = 887.0(2), b = 1307.6(3), c = 2002.3(4) pm, β = 94.13(3)°, Z = 4,3123 reflections, R = 0.072.
Synthese und Struktur der Basenaddukte von Kupfer(I)-Halogeniden mit Dimethylsulfid und Tetrahydrothiophen / Synthesis and Crystal Structure of Lewis Base Adducts of Copper(I)-Halides with Dimethylsulfide and Tetrahydrothiophene
Authors: Maelger Harald , Olbrich Falk , Kopf Jürgen , Abeln Dirk , Weiss Erwin
Published: March 2015

Copper complexes of the general formula [(CuX)a(L)b]n with L = tetrahydrothiophene (THT) or dimethylsulfide (DMS) and X = Cl, Br or I are formed by direct reaction of copper(I)halides with the corresponding ligands. All compounds have been characterized by X-ray crystallography. [(CuCl)(dms)]„ (la) crystallizes in the monoclinic space group P 21/c (a = 762.6(1), b = 638.0(2), c = 1154.8(3) pm, β = 108.10(2)° and Ζ = 4), [(Cul)(dms)1.5]n (le) in Ι 2/a (a = 1202.9(2), b = 780.0(2), c = 1714.6(2) pm, β = 97.92(2)° and Ζ = 8), [(CuCl)(tht)1.5]n (2a) in C 2/c (a = 1244.7(2), b = 1610.3(2), c = 988.9(2) pm,β = 111.51(1)° and Z = 8) and [(CuBr)(tht), 5]„ (2b) also in C2/c (a = 1159.6(2), b = 1638.8(3), c = 1015.1(2) pm, β= 109.44(1)° and Z = 8).

The crystal structures of [(CuBr)(dms)]„ (lb) and [(CuI)(tht)2]2 (2 c) are already known. In all structures the central copper atom is coordinated to two halide and two sulphur atoms with formation of a distorted tetrahedron. Two copper and two halogen atoms form planar Cu2X2 rings which are linked by the sulphur atoms of the thioethers. The thioether ligands can either function as bridges or they are coordinated “end on”. In la and lb a polymeric layer structure is found, while 1 c, 2a und 2b form polymeric chains. 2c forms dimers. Cu · · · Cu distances are in the range of 268.4 to 298.3 pm and Cu–S bond lengths are between 228.1 and 237.2 pm.
1-[4-{1,1′,1″,1‴,1′′′′-(1,3-Cyclopentadien-1,2,3,4,5-pentayl)pentakis}]-(4,1-phenylen)-alkanone und -benzoesäure pentaalkylester und deren Natrium- und Thallium(I)-Komplexe / 1-[4-{1,1′,1″,1‴,1′′′′-( 1,3-Cyclopentadiene-1,2,3,4,5-pentayl)pentakis}]-(4,1-phenylene)-alkanones and -benzoic Acid Pentaalkyl Esters and their Sodium- and Thallium(I) Complexes
Authors: Schumann Herbert , Kucht Homa , Kucht Andreas
Published: March 2015

Pentaphenylcyclopentadiene (1) reacts with acyl chlorides RC(O)Cl (R = CH3, C3H7, C5H11, C7H15) with formation of the corresponding [(cyclopentadiene pentayl)pentakis] (1,4-phenylene) alkanones C5H(C6H4C(O)R-4)5 (2a, 2c, 2d and 2e). 2 a reacts with KOCl in water/dioxane to yield C5Cl(C6H4C(O)OH-4)5 (3), which after reaction with C2H5OH and C5H11OH gives the pentaesters C5Cl(C6H4C(O)OR-4)5 (4b and 4d), and after reaction with (CH3)3SnH the corresponding [(cyclopentadiene pentayl)pentakis] benzoic acid pentaalkyl esters C5H(C6H4C(O)OR-4)5 (5b and 5d). Reaction of 2a, 2c, 2d, 2e and 5b with NaNH2 results in the formation of the sodium salts Na[C5(C6H4C(O)R-4)5] (6a, 6c, 6d and 6e) and Na[C5(C6H4C(O)OC2H5-4)5] (7). 2a, 2c, 2d, 2e, 5b and 5d react with TlOC2H5 to give the thallium(I) derivatives Tl[C5(C6H4C(O)R-4)5] (8a, 8c, 8d, 8e) and Tl[C5(C6H4C(O)OR-4)5] (9b and 9d). The 1H and 13C NMR spectra of the new compounds are reported and discussed.
Ν,Ν-Disubstituierte Amidoxim-Nachbargruppen in Cyclodehydrierungen / Assistance of Ν,Ν-Disubstituted Amidoximes in Cyclodehydrogenation Reactions
Authors: Möhrle Hans , Lessel Jürgen
Published: March 2015

o-(tert-Amino)benzamidoximes 6, Ν,Ν-disubstituted at the amid-N-atom of the nucleophilic moiety, are suitable neighbouring groups in cyclodehydrogenation reactions of tertiary amines using mercury(II)-edta. The kind of the N-substituents and the amount of oxidizing agent control the nature of the products, lactams 9 and anellated nitrones 8. The configuration of the tricyclic systems is determined by NMR spectroscopic methods. During the reaction an inversion of the configuration of the oxime moiety occurs, which is explained by an electrocyclic mechanism.
Silyl-, Germyl-, Stannyl- und Plumbyl-Komplexe von Vanadium(V) / Silyl, Germyl, Stannyl, Plumbyl Complexes of Vanadium(V)
Authors: Preuss Fritz , Wieland Thomas , Perner Jens , Heckmann Gert
Published: March 2015

The complexes t C4H9N=VCp(NH t C4H9)[E(SiMe3)3] (E = Si, Ge, Sn), tC4H9N=VCp(NHtC4H9)(EPh3) (E = Sn, Pb), tC4H9N=VCp(OtC4H9)[E(SiMe3)3] (E = Si, Ge) and tC4H9N=VCp(OtC4H9(SnPh3) have been prepared by reaction of chlorovanadium(V) compounds with LiER3(R=SiMe3, Ph). All complexes were characterized by NMR spectroscopy (1H, 51V), the stannyl complex 5 by X-ray diffraction analysis. The syntheses oftC4H9N=VCp(OtC4H9)(C6H5) and LiSn(SiMe3)3 · 3 THF are also described.
LiBa4[Mo2N7] • BaCl2: Dimere Anionen [Mo2N7]9- durch Kondensationsreaktion von Ba3[MoN4] in LiCl-Schmelzen / LiBa4[Mo2N7] • BaCl2: Dimeric Anions [Mo2N7]9- by Condensation Reaction of Ba3[MoN4] in LiCl Melts
Authors: Gudat Axel , Kniep Rüdiger , Maier Joachim
Published: March 2015

Pale yellow crystals of LiBa4[Mo2N7] • BaCl2 (monoclinic, P21/m; a = 1113.5(3), b = 605.8(1), c = 1122.7(3) pm; β = 95.65(2)°; Z = 2) were grown from the melt (LiCl/Ba3[MoN4], molar ratio 3:1, Tmax = 1050 °C) by cooling (5°C/h). The crystal structure contains dimeric units [Mo2N7]9- (eclipsed conformation; N-Mo-N: 173.7°; Mo-N(term.): 182.7(5)-186.1(8) pm; Mo-N(bridg.): 190.6(8) and 192.3(8) pm).
Synthese und Kristallstruktur von l,3-Di-tert-butyl-4,4-di-methyl-2-pentafluorphenyl-4,2-stannabora-cyclobutan / Synthesis and Crystal Structure of 1,3-Di-tert-butyl-4,4-di-methyl-2-pentafluorophenyl-4,2-stannabora-cyclobutane
Authors: Habben Carl D. , Heine Andreas , Sheldrick George M. , Stalke Dietmar
Published: March 2015

The synthesis and crystal structure of 1,3-di-tert-butyl-4,4-dimethyl-2-pentafluorophenyl-1,3,4,2-diazastannoboracyclobutane are reported.
TcN- und ReN-Komplexe mit Thio-β-diketonen / TcN and ReN Complexes of Thio-β-diketones
Authors: Uhlemann Erhard , Spies Hartmut , Pietzsch Hans-Jürgen , Herzschuh Rainer
Published: March 2015

Bis(thiodibenzoylmethanato)-nitridotechnetium(V) and -rhenium(V) as well as bis(1-phenyl-3-methyl-4-benzoyl-pyrazol-5-thionato)-nitridorhenium(V) have been prepared by the reaction of NBu4 [TcNCl4 or ReNCl2(PPh3)2 with the ligands. The dark brown complexes were characterized by elemental analysis, UV/VIS spectrometry and FAB mass spectra.
Thorexanthin, a New Carotenoid Pigment from the Caribbean Sponge Thorecta horridus
Authors: Fattorusso Ernesto , Lanzotti Virginia , Magno Silvana , Mayol Luciano
Published: March 2015

The red-pigmented caribbean sponge Thorecta horridus contains thorexanthin (3-methoxy-β-X-caroten-4-one) as a new carotenoid pigment. Its structure was determined by spectroscopic methods, including 2 D NMR experiments.
Addition von O- und C-Nucleophilen an Ruthenium-Schwefeldioxid-Komplexe, Struktur von [cpRu(dppm)(SO2Et)] / Addition of O- and C-Nucleophiles to Ruthenium Sulfur Dioxide Complexes, Structure of [cpRu(dppm)(SO2Et)]
Authors: Schenk Wolfdieter A. , Urban Peter , Stährfeldt Thomas , Dombrowski Eberhard
Published: March 2015

Ruthenium-sulfur dioxide complexes [cpRu(PR3)2(SO2)]Cl ((PR3)2 = (PPh3)2, Ph2PCH2PPh2(dppm), Ph2PC2H4PPh2(dppe)) add alkoxide to give sulfito complexes [cpRu(PR3)2(SO2OR′)] (R′ = Me, Et, /Pr). Reactions of [cpRu(dppm)(SO2)]Cl with LiR′ (R′ = Me, Bu, Ph), MgBrR′ (R′ = Et, CH=CH2) or ZnEt2 give sulfinato complexes [cpRu(dppm)(SO2R′)]. The structure of [cpRu(dppm)(SO2Et)] was determined by X-ray crystallography: Crystals are triclinic, space group P1̄, a = 11,008(1), b = 15,998(6), c = 17,813(2) Å, α = 92,30(2), β = 93,916(8), γ = 107,54(2)°, Z = 4. Salient features are a short Ru-S bond and relatively long S-O bonds which attest to the high π-donor ability of the pseudo-tetrahedral metal fragment.
Preparation and Crystal Structures of Th5Fe19P12 and ThFe4P2
Authors: Albering Jörg H. , Jeitschko Wolfgang
Published: March 2015

The new compounds Th5Fe19P12 and ThFe4P2 were prepared by reaction of the elemental components in a tin flux and their crystal structures were determined from single-crystal X-ray data. Th5Fe19P12 crystallizes with a new monoclinic structure type: C2/m, a = 2920.3(3), b = 379.18(3), c = 931.48(8) pm, β = 103.36(1)°, Z = 2, R = 0.031. ThFe4P2 is isotypic with SmNi4P2: P nnm, a = 1448.9(2), b = 1074.7(2), c = 376.98(4) pm, Z = 6, R = 0.030. Both compounds belong to the large family of structures with a metal : nonmetal ratio of exactly or nearly 2:1. In these phosphides all phosphorus atoms have nine metal neighbors: six are forming a trigonal prism with three additional neighbors capping the rectangular faces of the prism. In both structures the thorium atoms have trigonal prismatic or octahedral phosphorus coordination. Most iron atoms have the usual tetrahedral phosphorus environment. In addition, the structure of Th5Fe19P12 has iron atoms in rectangular and distorted square pyramidal phosphorus coordination, while the structure of ThFe4P2 contains iron atoms with only two or three phosphorus neighbors.
Übergangsmetallkomplexe mit Schwefelliganden, XCII. Oxidation von Thiolat-Amin- zu Schiffbase-Eisen(II)-Komplexen. Röntgenstrukturanalyse und Reaktivität von [Fe('N2S2')]2 (′N2S2′2- = Glyoxal-bis(2-mercaptoanil)(2 – )) / Transition Metal Complexes with Sulfur Ligands, XCII. Oxidation of Thiolate Amine to Schiff Base Iron(II) Complexes. X-Ray Structure Analysis and Reactivity of [Fe(′N2S2')]2 (′N2S2′2- = Glyoxal-bis(2-mercaptoanil)(2–))
Authors: Sellmann Dieter , Hannakam Marcus , Knoch Falk , Moll Matthias
Published: March 2015

Oxidation of [Fe(CO)2(′N2H2S2′')] (1) (′N2H2S2'2- = 1,2-ethanediamine-N,N′-bis(2-benzenethiolate)(2—)) gave insoluble [Fe(′N2S2')]2 (2) ('N2S2'2- = glyoxal-bis(2-mercaptoanil)(2—)). Dinuclear, thiolato-bridged 2 was characterized by single crystal X-ray structure analysis. It does not react with CO or H2, but yields bis or mono adducts with PR3 (R = Me, n-Bu, Cy).
Gasphasen-Reaktionen, 91 [1-3]
Thermische und heterogen-katalysierte N2-Abspaltung aus Azo-Verbindungen R–N=N–R (R = CH3, C3H5, C6H5) / Gas Phase Reactions, 91 [1-3]
Thermal and Heterogeneously Catalyzed N2 Elimination of Azo-Compounds R–N=N–R (R = CH3, C3H5, C6H5)
Authors: Bock Hans , Berkner Bodo
Published: March 2015

Thermal decompositions of azo compounds in the gas phase under reduced pressure are further investigated using photoelectron spectroscopic gas analysis. Passing diallyl, diphenyl and phenylmethyl derivatives either through a short-pathway pyrolysis (SPP) apparatus or through an external thermal reactor (ETR) results in the following fragmentations: Under nearly unimolecular conditions (SPP, 10-4 mbar pressure), diallyldiazene decomposes above 600 K to N2 and hexadiene-1,5 with the allyl radical as a detectable intermediate. The PE spectra recorded for diphenyldiazene above 1000 K (ETR, 1-2 mbar pressure) show N2, benzene, as well as traces of diphenyl. Phenylmethyldiazene yields above 800 K (SPP) predominantly N2, toluene, diphenyl and ethane with the methyl radical as the only detectable intermediate. Insertion of quartz wool into the pyrolysis tube (ETR) lowers the fragmentation temperatures, and in addition, above 850 K, HCN and aniline are PE spectroscopically identified. Surprisingly, this second reaction channel can be heterogeneously catalyzed: phenylmethyldiazene decomposes under 10-2 mbar pressure at a [Ni/SiO2] catalyst surface selectively to HCN and aniline.
Nitrosolate und verwandte Verbindungen, XII Nitrosolatokomplexe von Silber(I) / Nitrosolates and Related Compounds, XII Nitrosolato Complexes of Silver(I)
Authors: Olbrich Falk , Zimmer Bärbel , Kastner Michael , Schlabrendorff Carl von , Vetter Gottlieb , Klar Günter
Published: March 2015

X-ray analysis shows silver(I) aminomethylnitrosolate to have dimers as structural units, in which the W-shaped nitrosolate ions act as μ2-bridging ligands via the nitrogen atoms of the NO groups. The nearly planar dinuclear complexes form stacks, which are connected by additional AgO contacts leading to a kind of layer structure. These layers are held together by hydrogen bonds.

Mononuclear complexes of composition [Ag(nitrosolate)L2] can be obtained from silver(I) ethylnitrosolate and bipyridyl in methanol and from silver(I) benzylnitrosolate and triphenylphosphane in diethylether/liquid ammonia. In these complexes the nitrosolate ions are supposed to act as chelating ligands, again with N,N′-coordination.
[Mn(SPh)3Cl]2-, [Mn(SPh)3Br]2-, [Mn(SePh)4]2-, [Mn(TePh)4]2-, and [Co4(SPh)6Cl4]2-: New Mixed Halide/Thiolate and Chalcogenolate Complexes of Manganese and Cobalt
Authors: Tremel Wolfgang , Krebs Bernt , Greiwe Klaus , Simon Wolfgang , Stephan Hans-Oscar , Henkel Gerald
Published: March 2015

The reactions of 1:1:1 molar ratio mixtures of NaSPh/MnCl2/Et4NBr and NaSPh/CoCl2/ Et4NCl in methanol afford the compounds [Et4N]4[Mn(SPh)3Br][Mn(SPh)3Cl] (1) and [Et4N]2[Co4(SPh)6Cl4] · MeCN (2), respectively, with the following crystal data: a = 14.408(5), b = 13.788(4), c = 17.984(5) Å, β = 90.16(2)°, space group P21/c and Ζ = 4 for 1, and a = 21.976(4), b = 13.081(2), c = 22.012(4) Å, β = 105.48(1)°, space group P 21/c for 2. The structures were refined to R values of 0.049 and 0.037, respectively. Crystals of 1 contain both of the paramagnetic (S = 5/2) mononuclear anions [Mn(SPh)3Br]2- (3 a) and [Mn(SPh)3Cl]2- (3b). The anions 3 a and 3 b are superimposed in an averaged unit cell and thus occupy crystallographically equivalent sites, the positions of the chlorine and bromine atoms being unresolved. The monohalide species are distributed statistically over 93% of the total anion positions. The remaining 7% are occupied by the dihalide species [Mn(SPh)2Br2]2- (4a) and [Mn(SPh)2BrCl]2- (4b) in equal amounts. In all these cases the metal atoms exhibit a distorted tetrahedral stereochemistry. In crystals of 2 [Co4(SPh)6Cl4]2- anions (5) are observed which feature a {Co4S6Cl4} core consisting of a distorted (D2d) Co4 tetrahedron inscribed in a moderately irregular S6 octahedron defined by bridging S atoms of an adamantane type cage. The four chlorine atoms each bind to different Co atoms and define an outer Cl4 tetrahedron, such that the overall symmetry of the {Co4S6Cl4} core comes close to Td. The results presented show that [M3(SPh)3Hal6]3- type species reported for M = Fe are not as readily formed for M = Mn and Co in methanolic solution, where other species are found instead. Physical properties such as solid state susceptibilities and 1H NMR spectra confirm the identity of 1 and 2. Reactions of 4:1:2 molar ratio mixtures of NaSePh/MnCl2/Et4NCl and NaTePh/MnCl2/Et4NCl in methanol lead to [Et4N]2[Mn(SePh)4] (6) and [Et4N]2[Mn(TePh)4] (7). Both compounds crystallize in the monoclinic space group P21/n with a = 16.162(4), b = 15.323(4), c = 16.949(4) Å, β = 91.28(2)°, Z = 4 for 6, and a = 16.367(6), b = 15.641(7), c = 17.220(7) Å, β = 92.00(3)°, Z = 4 for 7. Their structures were refined to R = 0.077 and 0.026, respectively. Four benzeneselenolate and benzenetellurolate ligands provide a slightly distorted tetrahedral coordination about the Mn(II) center for 6 and 7, respectively. The Mn–Se and Mn–Te distances average 2.567 and 2.742 Å, the Se– Mn– Se and Te–Mn–Te angles range from 99.1(1) to 124.2(1) and from 94.7(1) to 127.0(1)°, respectively.
Dimere und Ketten in Praseodym(III)acetat-sesquihydrat, Pr(CH3COO)3·1,5 H2O / Dimers and Chains in Praseodymium(III)acetate-sesquihydrate, Pr(CH3COO)3 · 1.5 H2O
Authors: Lossin Adalbert , Meyer Gerd
Published: March 2015

Pr(CH3COO)3· 1.5 H2O crystallizes with the triclinic system, P̄1̄ (no. 2), Z = 4, a = 844.2(4), b = 1009.8(5), c = 1340.1(7) pm, α = 87.10(5), β = 76.25(6), y = 75.65(2)°, Vm = 161.9(1) cm3/mol, R = 0.049, Rw = 0.035. The crystal structure contains centrosymmetric dimers {[Pr(CH3COO)4(H2O)]-}2 and one-dimensional chains ∞
1[Pr(CH3COO)2(H2O)]+ along the [100] direction. Both units are built up by bridging acetate groups. The chains are linked by the dimers to layers parallel (101) sharing oxygen atoms. Crystal water molecules between these planes form hydrogen bonds to neighbouring layers.
Synthese und Charakterisierung achtgliedriger Cyclometallaphosphazene von Niob(V) und Titan(IV) sowie cyclischer und acyclischer Verbindungen von Molybdän(VI) mit Perfluoralkyl-Gruppen – Kristallstruktur von [Ph2PNONbCl3]2 · 4 MeCN / Synthesis and Characterization of Eight-Membered Dimetallacyclophosphazenes with Niobium(V) and Titanium(IV) and Cyclic as well as Acyclic Compounds of Molybdenum(VI) Containing Perfluoroalkyl-Groups – X-Ray Crystal Structure of [Ph2PNONbCl3]2·4MeCN
Authors: Olms Petra , Roesky Herbert W. , Keller Klaus , Noltemeyer Mathias
Published: March 2015

Me3SiOPPh2NSiMe3 (1) reacts with NbCl5 and CpTiCl3 to form the eight-membered ring compounds [Ph2PNONbCl3]2 (2) and [Ph2PNOTiClCp]2 (3). The reaction of (C2F5)2P(Cl)=NSiMe3 (4) with MoO2Cl2 and MoOCl4 in CH2C12 quantitatively yields the compounds [MoOCl3-O-P(C2F5)2=NSiMe3]4 (5) and (C2F5)2P(Cl)=N-MoOCl3 (6).

Through recrystallization from MeCN, compound 2 has been isolated and characterized by means of X-ray analysis as the MeCN adduct 2 a.
Über Sulfide und Oxidsulfide des Samariums / On Sulfides and Oxysulfides of Samarium
Authors: Lissner Falk , Schleid Thomas
Published: March 2015

Stoichiometric oxidation of SmCl2 with sulfur in the presence of NaCl (evacuated silica vessel, 850 °C, 7 d) results in the formation of A—Sm2S3 (orthorhombic, Pnma (no. 62), a = 737.64(5), b = 397.44(3), c = 1536.26(9) pm, Z = 4, Rw = 0.017). In contrast, C—Sm2S3 (cubic, I43 d (no. 220), a = 844.71(3) pm, Z = 5.333, Rw = 0.017) is obtained upon reaction of the elements (Sm : S = 2 : 3) under otherwise analogous conditions. According to Sm2.67⬜0.33S4 it represents a defect-variant of mixed-valence Th3P4-type Sm3S4 (a = 852.39(3) pm, Z = 4, Rw = 0.013) which forms whenever reducing tantalum is used as container material instead of silica tubing. Ubiquitous oxidic impurities thereby also react to yield the oxygen-poor oxysulfides Sm10S14O (tetragonal, 141/acd (no. 142), a = 1485.96(4), c = 1974.04(8), Z = 8) and Sm2OS2 (monoclinic, P21/c (no. 14), a = 840.54(6), b = 706.20(5), c = 697.72(5) pm, β = 99.294(6)°, Ζ = 4, Rw = 0.024) as by-products. Regardless of the container material, NaCltype SmS (cubic, Fm 3 m (no. 225), a = 596.04(3) pm, Z = 4) emerges as product from equimolar oxidation of samarium with sulfur. Reactions of Sm2S3 with Sm2O3 in 1: 2 molar ratios are suitable to produce Ce2O2S-type Sm2O2S (trigonal, P 3 ml (no. 164), a = 389.25(3), c = 671.18(7) pm, Z = 1) even in tantalum capsules at 850 °C when some NaCl is added as a flux.
Umsetzungen von Methylphosphanen (CH3)nPCl3-n(n = 1-3) mit Methylchlorsulfan und Kristallstrukturen von (CH3)3PSCH3
+I- und CH3P(SCH3)Cl2
+SbCl6
- / Reactions of Methylphosphines (CH3)nPCl3-n(n = 1-3) with Methylchlorosulfane and Crystal Structures of (CH3)3PSCH3
+I- and CH3P(SCH3)Cl2
+SbCl6
-
Authors: Minkwitz Rolf , Medger Gernot , Greth Rüdiger , Preut H.
Published: March 2015

The new thiophosphonium compounds (CH3)„P(SCH3)Cl3-n
+Cl- (n = 1-3) are prepared by reaction of methylphosphines (CH3)„PC13_„ (n = 1-3) with CH3SC1 in CH2C12. CH3P(SCH3)Cl2
+Cl- reacts with A1C13 or SbCl5 to give the tetrachloroaluminate and the hexachloroantimonate, respectively. Likewise (CH3)2P(SCH3)Cl+SbCl6
- is formed from the chloride and SbCl5. All compounds are characterized by vibrational and NMR spectroscopy. CH3P(SCH3)Cl2+SbCl6- crystallizes in the monoclinic space group P21/n with a = 929(2), b = 1095(2), c = 1436(3) pm, β = 93,1(2)° and Z = 4. (CH3)3PSCH3
+I- crystallizes in the same space group with a = 705,2(4), b = 1360,6(8), c = 941,8(4) pm, β = 93,85(4)° and Z = 4.
Schwingungsspektren und Kraftfeldberechnungen an Fluorphosphoniumkationen PX4–nFn
+ (X = H ,D; n = 0-4) / Vibrational Spectra and Force-Field-Calculations of Fluorophosphonium Cations PX4–nFn
+ (X = H, D; n = 0-4)
Authors: Minkwitz Rolf , Lennhoff Dirk , Sawodny Wolfgang , Härtner Heinz
Published: March 2015

The vibrational spectra of all members of the fluorophosphonium cation series are reported, including the protonated and deuterated species PX4-n Fn
+ (X = H, D; n = 0-4). The unequivocal assignment of the vibrations follows from the isotopic shifts and by means of force field calculations. Furthermore, the force constants are discussed for the complete series.
Schwingungsspektren und Normalkoordinatenanalyse der Bromo-Iodo-Osmate(IV), [OsBrnI6-n]2-, n = 0-6 / Vibrational Spectra and Normal Coordinate Analysis of Bromo-Iodo-Osmates(IV), [OsBrnI6-n]2-, n = 0-6
Authors: Preetz W. , Manthey M.
Published: March 2015

The IR and Raman spectra of the ten bromo-iodo-osmates(IV) [OsBrnI6-n]2-, n = 0-6, including the geometrical isomers for n = 2, 3, 4, have been recorded at low temperature. The vibrational spectra are completely assigned according to point groups Oh, D4h, C4v, C3v, and C2v, as supported by normal coordinate analyses based on a general valence force field. Due to the different trans-influences Br<I in asymmetric axes Br′–Os–I′, the Os–I′ bonds are strengthened and the Os–Br′ bonds are weakened, as indicated by valence force constants, for Os–I′ on average 4% higher and for Os–Br′ 4% lower, as compared with the values calculated for symmetric I–Os–I and Br–Os–Br axes, respectively.
Beryllium Coordination to Bio-Ligands: Isolation from Aqueous Solution and Crystal Structure of a Hexanuclear Complex of Be2+ with Glycolic Acid, Na4[Be6(OCH2CO2)8]
Authors: Kumberger O. , Riede J. , Schmidbaur H.
Published: March 2015

Beryllium and its compounds are highly toxic to most living cells, but the mechanisms of the interference with the biological substrates on the molecular level is not understood. From observations in (attempted) chemotherapy of beryllium poisoning using a variety of complexing agents it has been concluded that Be2+ is interacting predominantly with carboxyl as well as hydroxyl functions of protein bio-polymers, with complete deprotonation of the alkoxy or phenoxy functions involved. As a first support for this hypothesis, an analytically well-defined beryllium complex of glycolic acid has now been isolated from aqueous solutions under nearphysiological conditions, crystallized and its structure determined by X-ray diffraction. The hexanuclear complex features beryllium in two different environments, mono- and bis-chelated by glycolate ligands with deprotonated hydroxyl groups. In 9Be-NMR studies of aqueous solutions of the complex (pH 6) the persistence of complexation in two different environments of Be2+ could also be confirmed. The new structure may serve as a model for beryllium complexation with larger bio-ligands.
The First Complexes of Tetragoldmethane CAu4
Authors: Schmidbaur H. , Steigelmann O.
Published: March 2015

Treatment of C[B(OMe)2]4 with four equivalents of a (tert-phosphine)gold(I) chloride LAuCl with L = P(c-C6H11)3 or (2-MeC6H4)3P in the presence of CsF in hexamethylphosphoric triamide (HMPT) affords the first complexes of the type (LAu)4C. The product is formed together with salts (LAu)5C+BF4- as the by-product for L = tricyclohexylphosphine, from which it can be separated by fractional crystallisation. With Ph2(2-MeCH4)P only the hexacoordinate species (LAu)6C2+2 BF4- is obtained, while with Ph(2-MeC6H4)2P a mixture of (LAu)6C2+ and (LAu)5C+ salts is generated. The title compounds are stable, colourless solids readily identified by standard analytical and spectroscopic techniques, including 13C NMR of 13C-enriched material.
Preparation, IR and X-Ray Crystal Structure Studies of Tl(I)-2-pyridyl-cyanoxime Complex
Authors: Gerasimchuk N. Nikolay , Nagy László , Schmidt H.-G. , Noltemeyer Mathias , Bohra Rakesh , Roesky Herbert W.
Published: March 2015

The thallium(I)-2-pyridyl-cyanoxime complex was prepared in a 82% yield. An X-ray crystallographic study of C7H4N3OT1 (Space group P21/c, a = 4.134(1), b = 8.875(2), c = 22.217(6) Å, β = 92.55(2)°, Ζ = 4, R = 4.36%, wR = 3.94% for 930 reflections) showed that the complex contains thallium(I) in a trigonal bipyramidal arrangement.
Kristallstruktur von K4O(CN)2 / Crystal Structure of K4O(CN)2
Authors: Hardt Christian , Vogt Petra , Sabrowsky Horst
Published: March 2015

Colorless K4O(CN)2 has been prepared. The compound crystallizes in the tetragonal anti-K2NiF4 structure type (space group I4/mmm) with a = 515.5(1) and c = 1606.7(3) pm, Z = 2. The structure was determined by single crystal X-ray diffraction, R = 3.35%.
Crystal Structure Investigation of Two Polymeric Chromium(III) Azide Complexes; KCr(pyridine)4(N3)4 and RbCr(pyridine)3(N3)4. A Structure Containing μ(l,3) and μ(1,1,3) Bridging Azido Ligands between Chromium and Rubidium Centered Polyhedra
Authors: Goher M. A. S. , Abu-Youssef M. A. M. , Mautner F. A. , Fritzer H. P.
Published: March 2015

The structures of two polymeric complexes of chromium(III) azide with pyridine, KCr(py)4(N3)4 (1), and RbCr(py)3(N3)4 (2), were determined by X-ray crystallography. Crystal data: 1, C20H20N16CrK, monoclinic, space group C2/c, a = 1611.2(5), b = 1050.6(3), c = 1609.0(5) pm, β = 91.69(3)°, Ζ = 4 and Rw = 0.037 for 923 diffractometer data; 2, C15H15N15CrRb, monoclinic, space group P21/n, a = 1311.9(3), b = 1139.0(4), c = 1523.3(4) pm, β = 109.39(2)°, Ζ = 4 and Rw = 0.046 for 2336 data.

The crystal structure of 1 contains six-coordinated chromium and potassium cations with two pyridine ligands and four µ(1,3) bridging azido groups forming a three-dimensional network structure. The chromium atoms are trans-coordinated by the pyridine ligands, whereas the potassium cations are cis-coordinated. The polymeric complex 2 features di-µ(l,1,3) azido bridged CrRbN2 rings, distorted octahedral chromium(III) coordination geometry, sevencoordinated rubidium, and di-μ(1,3) azido bridges which link the binuclear RbCr(pyridine)3(N3)2 moieties into infinite chains parallel to the b axis.
Electronic Spectra and Photochemical Properties of Acetyldihydroquinolinones
Authors: Bakalova Snezhana , Kavrakova Ivanka
Published: March 2015

The absorption and luminescence properties of 6-acetyl-2,3-dihydro-4(1H)-quinolinone are described and compared to those of the parent 2,3-dihydro-4(1H)-quinolinone. The character of the electronic transitions is determined by PPP quantum chemical calculations.

An N-acyl migration leading to the formation of 6-acetyl-2,3-dihydro-4(1H)-quinolinone takes place upon UV irradiation or heating with polyphosphoric acid of 1-acetyl-2,3-dihydro-4-(1H)-quinolinone. A radical mechanism of the photochemical rearrangement is proposed.
Notizen: Die Kristallstruktur von [CuICu211(CN)4(′N2S′)2[SCN (′N2S′ = 1-Thia-4,7-diazacyclononan) / Crystal Structure of [CuICu2
II(CN)4(′N2S′)2]SCN (′N2S′ = 1-Thia-4,7-diazacyclononane)
Authors: Wasielewski Klaus , Mattes Rainer
Published: March 2015

The polynuclear complex

[CuICu2II(CN)4(′N2S′)2]SCN was obtained by gel diffusion of the sodium salt of 4,7-Bis(dithiocarboxylato)-1-thia-4,7-diazacyclononane and K3Cu(CN)4. Its structure consists of an infinite band of edge-sharing CuI(CuII)4 tetrahedra, where the Cu1 and CuII ions are connected via CN~ bridges. CuII is additionally coordinated by the N2S macrocycle 1-thia-4,7-diazacyclononane. Crystal data: monoclinic, space group C 2/c, a = 1936.6(4), b = 1287(3), c = 1337(2) pm, β = 133.07(2)°, Ζ = 4, 2336 reflections, 203 parameter, R (Rw) = 0.027 (0.031).
Silaheterocyclen, XXIV. / Silaheterocycles, XXIV.
Authors: Auner Norbert , Weingartner Armin W. , Herdtweck Eberhardt
Published: March 2015

The 1-amino-2-neopentylsilenes 5-8 are formed in the reaction of LitBu with the aminovinylsilanes 1-4 in n-pentane (addition of LitBu to the vinylic double bond with subsequent 1,2-elimination of LiCl). The α-Li adducts initially formed are trapped by Me3SiOSO2CF3 to yield α-SiMe3-silanes. The silenes undergo insertion reactions into the Si—O bond of Me3SiOMe. In the absence of any trapping reagent dimerization occurs. One of the 1,3-disilacyclobutanes thus formed (15) could be examined by X-ray diffraction. Reacting with 1,3-butadienes the chlorosubstituted silenes 5 and 8 yield [2 + 2]-cycloaddition products. With 1,3-cyclohexadiene Diels-Alder adducts are also obtained, but with cyclopentadiene the [4+2] adducts are formed exclusively. Products of an ene-reaction are observed upon treatment of 2,5-norbornadiene with the silenes 5 and 8.

The methylsubstituted silene 6 does not undergo any cycloaddition reaction at all, while from silene 7 only traces of the cycloadducts are produced. Both species mainly yield the dimers. The preference for the [2+2] reaction type, exhibited by the silenes 5 and 8, is due to their polarity. The almost complete absence or low yield of any cycloaddition products from 6 or 7 can be correlated with the energy levels of their frontier molecular orbitals. The distribution of the disilacyclobutanes and cycloaddition product isomers is explained by the characteristics of the stereospecifically Ε-configurated silenes. The product distribution can also be rationalized considering the ambiphilic nature of the system ViRR′SiCl/Li1Bu.
K2[SeMo3O13] · 3,5 H2O und K2[SMo3O13] · 4 H2O-Verbindungen mit kettenförmigen Heteropolyanionen des SeVI und SVI / K2[SeMo3O13] · 3.5 H2O and K2[SMo3O13] · 4 H2O-Compounds with Chain-Like Heteropoly-Anions of SeVI and SVI
Authors: Robl Christian , Haake Karin
Published: March 2015

Colourless monoclinic (space group C2/m) single crystals up to 1 mm long of K2[SeMo3O,3] · 3.5 H2O and K2[SMo3O13] · 4 H2O, respectively, were prepared from aqueous solution. Crystal data: Se compound a = 1703.5(2), b = 1088.5(1), c = 865.3(1) pm, β = 109.666(9)°, 1670 unique reflections, 123 parameters, Rg = 0.0233; S compound a = 1702.7(2), b = 1079.6(1), c = 884.9(1) pm, β = 112.248(9)°, 1458 unique reflections, 123 parameters, Rg = 0.0250. Both compounds cleave very easily to thin fibres. The chain-like heteropoly-anions are composed of chains of edge-sharing MoO6 coordination octahedra and XO4 tetrahedra (X = S, Se) linked to three different octahedra through common corners. Differential thermal analysis indicates that no decomposition occurs with K2[SMo3O13] · 4 H2O except removal of water of crystallization up to 500°C. Decomposition to various potassium molybdates takes place between 460 and 470°C with the Se compound.
Na6[TeMo6O24]·22 H2O – A Layered Heteropoly Compound with the Chain-Like Polycation {Na3(Η2O)1111}n
3n+
Authors: Robl Christian , Frost Mona
Published: March 2015

Colourless triclinic single crystals of Na6[TeMo6O24] · 22 H2O were grown from aqueous solution (space group P 1, a = 1030.89(9), b = 1056.7(1), c = 1106.32(9) pm, α = 90.120(7), β = 115.220(6), γ = 105.195(7), Ζ = 1, 295 Κ, 336 parameters, 3181 reflections, Rg = 0.0186). There are three crystallographically independent Na+ cations. Two of them are coordinated octahedrally by water molecules only. The third Na+ cation is bound to five H2O and one oxygen atom (O(4)) belonging to the Anderson-Evans type anion [TeMo6O24]6-. The sodium-centered coordination octahedra are linked by common edges exclusively formed by water molecules to yield chain-like polycations {Na3(H2O)11}n
,3n+ which are bound by the Na(1)-O(4) contact to the anions situated on crystallographic centers of inversion forming a layer-like arrangement. Further connections between the polycations and the [TeMo6O24]6- anions are established by hydrogen bonds involving all the oxygen atoms of the anion except O(4) as almost equivalent proton acceptors regardless of their bonding mode to Te or Mo.
Zur Reaktion von (COD)PtCl2 mit 1,4-Bis-[di(t-butyl)phosphino]butan (dtbpb). Kristallstruktur von [(t-Bu)2P(CH2)4P(t-Bu)2 – (C8H12) – PtCl]+ Cl- / On the Reaction of (COD)PtCl2 with 1,4-Bis-[di(t-butyl)phosphino]butane (dtbpb). Crystal Structure of [(t-Bu)2P(CH2)4P(t-Bu)2–(C8H12)–PtCl]+Cl-
Authors: Wurst K. , Strähle J.
Published: March 2015

Whereas (COD)PtCl2 usually reacts with bidentate phosphine ligands under substitution of the COD ligand, the reaction with the newly synthesized 1,4-bis-[di(t-butylphosphino)] butane results in the insertion of COD into one Pt-P bond affording [(t-Bu)2P(CH2)4 P(t-Bu)2-(C8H12)-PtCl]+Cl- (1). 1 crystallizes in the monoclinic space group C2/c with a = 3912.8(8), b = 1765.6(3), c = 3851.3(4) pm, β = 118.36(2)°, Ζ = 24. In the cation of 1 the second C=C bond remains coordinated to the central Pt2+ ion. The square-planar coordination of Pt2+ ion is completed by a Cl ligand and the second P atom of the phosphine ligand. The inserted C-C bond is elongated to 149(5) pm with respect to the coordinating C=C bond of 133(6) pm.
Inter- und intramolekularer Energietransfer und Ladungstrennung in kovalent gebundenen Cyanin-Farbstoff-Viologen-Systemen / Inter- and Intramolecular Energy Transfer and Charge Separation in Covalently Linked Cyanine Dye-Viologen Systems
Authors: Bauer Rupert , Königstein Christian
Published: March 2015

As described by many authors, covalently linked dye-electron accepting group systems may provide a very efficient intramolecular fluorescence quenching and electron transfer. Due to the very fast thermal back reaction, no stable charge separation can be achieved. In contrast, J-aggregates of cyanine dyes (1,1′-diethyl-2,2′-cyanine iodide = 1) containing some molecules with covalently linked viologen groups (1-[3-[2-[(1-ethyl-2(1 H)-chinolinyliden)methyl]-chinolinium-l-yl]propyl]-1′-methyl-4,4′-bipyridinium triiodide = 2, 1,1′-(4,4′-bipyridinium-1,1′-diyldi-5,1 -pentandiyl)bis[2-[(1-ethyl-2(1H)-chinolinyliden)methyl]chinolinium] tetrachloride = 3) show an increase in charge separation. Hydrogen production experiments in these organized assemblies, both via inter- (with methyl viologen) and intramolecular (with 2 or 3) charge separation were successful. Hydrogen production experiments based on intramolecular charge separation gave even higher quantum yields than via intermolecular reaction steps. In contrast, hydrogen production experiments with dilute aqueous solutions (no aggregates) with 2 or 3 failed in the absence of methyl viologen (MV2+) due to the fast intramolecular back reaction. In the presence of MV2+ compounds 1-3 were able to produce H2 only when irradiated with near UV-light (λ > 280 nm). Irradiation of these solutions with visible light (λ > 400 nm) resulted in no H2 production. This is attributed to competing nonradiative desactivation processes. Dilute aqueous solutions of 1-3 gave also no visible emission (λ > 400 nm) in the absence of (additional) quenching molecules. So a further progress was achieved by using the J-aggregates: competing nonradiative desactivation processes (of the excited dye molecules) were diminished in J-aggregates.
Synthesis and Use of Pentafluorophenyl 6-(Biotinylamido)hexanoate An Alternative Reagent for Labelling of Proteins with Biotin Moiety
Authors: Somlai Csaba , Berényi Maria , Maróy Peter
Published: March 2015

The protein biotinylating agent, pentafluorophenyl 6-(biotinylam ido)hexanoate (3) was synthesized. A straightforward synthetic route, biotin, biotin pentafluorophenyl ester (1), 6-(biotinylam ido)hexanoate (2) and pentafluorophenyl 6-(biotinylam ido)hexanoate (3) was followed. This agent was used for biotin-labelling of different proteins, bovine serum album in, immunoglobulin, horseradish peroxidase and β-galactosidase. Optimal conditions for the labelling were determined, as well as the influence of biotin-tagging to the biological activity of the proteins. An optimal ratio of the biotinylating agent to protein resulted in effective biotinylation without a significant decrease in the activity of the labelled enzyme. The labelled proteins proved to be suitable for immunodetection of proteins in both microplate and Western blot immunohistochemistry, as well as in a competitive steroid ELISA of testosterone and 20-hydroxyecdysone.
Reaktionen von Pyridin-Basen mit Na/K-Legierung und Diorganylaminodifluorboranen / Reactions of Pyridine-Bases with Na/K-Alloy and Diorganylaminodifluoroboranes
Authors: Maringgele Walter , Meller Anton , Dielkus Sven , Herbst-Irmer Regine
Published: March 2015

Lutidines react with Na/K alloy and diorganylaminodifluoroboranes in n-hexane. The products formed depend upon the position of the methyl groups. While from 3,4-lutidine (C) the bis(lutidinyl)aminoboranes 2 - 5 are obtained, the 2,4-, 2,5-, and 3,5-lutidines (F, G, H) give the 11 a, 1 lb-dihydro-[1,3,2]-diazoborolo-[5,l-b;3,4-b']-dilutidines 11-17. 4-Picoline reacts analogously to give 10. Pyridine (A) and collidine (B) give adducts with borane. From 2,3-lutidine (D), the 1,4-dihydro-l,4-bis(fluoraminoboryl)-2,3-lutidine 8 is obtained. 1H, 11B, 13C, 19F, 29Si, 15N NMR and MS data are given. For 8 and 14 the X-ray structures are reported.