bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Pyoverdin-Type Siderophores from Pseudomonas fluorescens
Authors: Mohn G. , Taraz K. , Budzikiewicz H. 
Published: March 2015

The structures of two new pyoverdins (GM-I and GM-II) isolated from the culture medium of Pseudomonas fluorescens have been elucidated by spectroscopic methods and degradation studies. The pyoverdins consist of a chromophore which could be identified as (1 S)-5-amino-2,3-dihydro-8,9-dihydroxy-1 H-pyrimido[1,2-a]quinoline-1-carboxylic acid substituted at the amino group with a 3-carboxypropanoyl or a succinamoyl residue and at the carboxy group with the N-terminus of D-Ala-D-Lys-Gly-Gly-D-threo-(OH)Asp-D-Glu-D-Ser-L-Ala-D-Ala-D-Ala-L-Ala-L-N5-(OH)Orn.
According to the “short-hand” nomenclature proposed in [2]*** the two compounds should be characterized as pyoverdin-Q-akGGd'qsAaaAO′*-SUCA and pyoverdin-Q-akGGd'qsAaaAO′ *-SUC
Metal Tetrahydroborates and Tetrahydroborato Metalates, 15 [1]. An 11B and 113Cd NMR Study of MBH4–CdCl2 Systems in Dimethylformamide and the X-Ray Structure of CdCl2 · 2 DMF
Authors: Linti Gerald , Nöth Heinrich , Thomann Martina 
Published: March 2015

CdCl2 dissociates in dimethylformamide into the species Cd(DMF)6
2+, CdCl(DMF)5
+ and CdCl3
- as determined by 113Cd NMR spectroscopy. 11B and 113Cd NMR spectra of MBH4/CdCl2 solutions in this solvent show the presence of complexes [CdCl2
-n(BH4)n+1]- with rapid exchange of BH4
- and Cl- at ambient temperature. There is no evidence that Cd(BH4)2 is formed in a metathetical reaction.
The crystal structure of CdCl2 · 2 DMF has been determined. It is a coordination polymer containing hexacoordinated Cd atoms with the DMF molecules in cis-position. Coordination of DMF occurs via the carbonyl oxygen atoms.
Notizen: Synthesis and Structure of an 1,3-Dibora-2,5-disilacyclohexane Derivative
Authors: Wong-Chi-Man Wong-Wee-Choy , Pritzkow Hans , Siebert Walter 
Published: March 2015

Hydroboration, 3,3-Dimethyl-(e)-1-chlorodimethylsilyl-1-chloro-dimethylaminoboryl-butene-1,1,3-Bis(dimethylamino-2,2,5,5-tetramethyl-4,6-bis-(t-butylethylene)-1,3-dibora-2,5-disilacyclohexane
Hydroboration of chlorodimethyl(3.3-dimethylbutynyl)silane with HBCl2/BCl3 yields 3.3-dimethyl-(e)-1-chlorodimethylsilyl-1-dichloroboryl)-butene-1 (1 a), in which a chlorine atom at the boron can be substituted using Me3SiNMe, to give the corresponding chlorodimethylaminoboryl derivative 1 b. Dehalogenation of 1 b with Na/K alloy does not lead to the three-membered ring compound 2, but surprisingly yields the 1,3-dibora-disilacyclohexane derivative 3. The X-ray structure analysis shows a six-membered ring with a chair conformation, a small angle B 1–Si 2–B 1′ = 95.4(1)°, and long Si–B bonds (2.038 Å).
Synthese und Röntgenstrukturanalyse einer acyclischen Schwefel-Stickstoff-Verbindung mit einer S5N4-Kette / Synthesis and X-Ray Structural Analysis of an Acyclic Sulfur Nitrogen Compound with an S4N5 Chain
Authors: Wolmershäuser G. , Mann P. R. 
Published: March 2015

The title compound was obtained on reduction of R2S4N3
+Cl- via dismutation. Its crystal structure was determined by X-ray diffraction.
(CH3-C6H4)2-S5N4: The conformation of the SN chain closely resembles that of (SN)x; however, the bond-distances are in accordance with the assumption of alternating S(II) and S(IV) atoms.
Die Wechselwirkung von N3F mit Lewis-Säuren und HF. N3F als möglicher Vorläufer für die Synthese von N3
+-Salzen / The Interaction of N3F with Lewis-Acids and HF. N3F as Possible Precursor for the Synthesis of N3
+ Salts
Authors: Schatte Gabriele , Willner Helge 
Published: March 2015

Triazadienyl fluoride, N3F, forms stable adducts with BF3 and AsF5 at low temperatures, as demonstrated by infrared measurements. The Lewis acids are bonded to the Nα-atom of N3F, as deduced from the data for 15N-isotopically enriched N3F. The basicity of N3F is comparable to that of ethine and ethene, according to the HF stretching frequency of the N3F/HF complex isolated in an argon matrix. Despite the low NF bond energy (&lt; 150 kJ/mol), abstraction of the fluoride ion and formation of an N3
+ salt was not possible.
The different behavior of N3F and ClN3 towards Lewis acids is discussed.
Die Reaktionen von Wolframhexachlorid mit überschüssigem 2,2-Dimethylpropylidinphosphan; die Kristallstrukturen von WCl5P2(C5H9)3, WCl4P5(C5H9)5 und [C3(C4H9)3]+[WCl5(C4H9C≡CC4H9)]- / The Reactions of Tungsten Hexachloride with Excess 2,2-Dimethylpropylidynephosphane; the Crystal Structures of WCl5P2(C5H9)3, WCl4P5(C5H9)5, and [C3(C4H9)3]+[WCl5(C4H9C=CC4H9)]⁻
Authors: Weller Frank , Pauls Irene , Dehnicke Kurt , Becker Gerd 
Published: March 2015

The reaction of tungsten hexachloride with excess 2,2-dimethylpropylidynephosphane, C4H9—C≡P, leads to the tungsten phosphaalkyne clusters WCl5P2(C5H9)3 and WCl4P5(C5H9)5, as well as to the tris(t-butyl)cyclopropenium pentachloro tungsten alkyne complex [C3(C4H9)3]+[WCl5(C4H9C≡CC4H9)]-. All complexes were characterized by X-ray structure determinations.
WCl5P2(C5H9)3: Space group P2,/n, Z = 8,4653 observed unique reflexions, R = 0.033. Lattice dimensions at 20 °C: a = 1577.8(2), b = 1661.3(1), c = 1869.8(2) pm, β = 110.64(1)°. The compound has a molecular structure, in which the tungsten atom is surrounded by three chlorine atoms, three carbon atoms with W—C distances of 182, 230, and 231 pm, and by one phosphorus atom with W—P = 246 pm.
WCl4P5(C5H9)5: Space group P21/c, Z = 4, 3517 observed unique reflexions, R = 0.043. Lattice dimensions at 20 °C: a = 1770.0(2), b = 1032.9(2), c = 1876.0(3) pm, β = 102.86(1)°. The complex has a molecular structure, in which the tungsten atom is surrounded by two chlorine atoms, two carbon atoms with W—C distances of 189 and 215 pm, as well as by four phosphorus atoms with W — P distances of 242, 250, 264, and 268 pm.
[C3(C4H9)3]+[WCl5(C4H9C=CC4H9)] : Space group P21/c, Ζ = 4, 3284 observed unique reflexions, R = 0.052. Lattice dimensions at 20 °C: a = 941.5(3), b = 1762.2(6), c = 1903.5(7) pm, β = 92.27(3)°. The compound consists of tris(t-butyl)cyclopropenium ions, and anions [WCl5(C4H9C=CC4H9)]⁻, in which the bis(t-butyl)alkyne ligand is coordinated side-on, corresponding to a cyclopropene type structure with W—C distances of 198 pm.
Preparation, Spectral and Structural Characterization of Two Polymeric 1:1 Mixed Ligand Complexes of Copper(II) Azide with 4-Methylquinoline and 2-Methylpyridine
Authors: Goher Mohamed A. S. , Mautner Franz A. 
Published: March 2015

Two 1:1 mixed ligand complexes of copper(II) azide with substituted quinoline and pyridine, namely catena di-μ(1,1)-azido-(4-methylquinoline)copper(II) (1) and catena di-μ(1,3)-azido-[di-μ(1,1)-azido-bis(2-methylpyridine)dicopper(II)] (2) have been prepared and characterized by X-ray crystallography.
Crystal data: 1, C10H9N7Cu, space group P21/c, a = 577.8(2), b = 2202.3(5), c = 919.9(2) pm, β = 93.92(2)°, Ζ = 4, and R = 0.035 for 1293 observed MoKa data; 2, C6H7N7Cu, space group P21/a, a = 823.7(2), b = 1303.8(4), c = 895.3(3) pm, β = 112.23(2)°, Ζ = 4, and R = 0.022 for 2133 observed ΜοΚα diffractometer data. In the structure of 1, the Cu(II) has a strongly distorted trigonal bypyramidal coordination, where both azido groups function as μ(1,1) bridging ligands resulting in a columnar structure along the a axis. The polymeric complex 2 has a less distorted square pyramidal structure; one half of the azide groups act as μ(1,1) bridging ligands to form centrosymmetric dimers. These dimeric units are further connected by the remaining μ(1,3) bridging azido groups to form layers within the ab-plane. Infrared and electronic spectral data are also presented and discussed.
The Crystal and Molecular Structure and Properties of Diaqua[N-salicylidene – (S) – (+) – glutamato]copper(II) Monohydrate
Authors: Krätsmár-Šmogrovič J. , Pavelčík F. , Soldánová J. , Sivy J. , Seressová V. , Žemlička M. 
Published: March 2015

The crystal and molecular structure of the title complex was determinated by single crystal X-ray diffraction (R = 0.066 for 1059 observed reflections). The approximately square-pyramidal coordination of Cu(II) results from donor atoms O(12), O(1), N(1), O(5) of one H2O molecule as well as the tridentate Schiff base dianion ligand and from the weakly bonded O(1) donor atom of one other H2O molecule in the apical site.
The magnetic behaviour of the complex studied obeys the Curie—Weiss law in the temperature range 94—309 K with a small value of the Weiss constant, θ = 1.4 Κ. A similar cryomagnetic behaviour is also characteristic for the anhydrous compound, [N-salicylidene—(S)—(+)-glutamato]copper(II), obtained by thermal dehydration of the title complex.
Übergangsmetallkomplexe mit Schwefelliganden, LXXV / Transition Metal Complexes with Sulfur Ligands, LXXV
Authors: Sellmann Dieter , Fünfgelder Stefan , Knoch Falk 
Published: March 2015

[Ni(′NHS′4)]2 (′NHS′4
2- = 2,2′-bis(2-mercaptophenylthio)diethylamine(2-)) was synthesized from Ni(ac)2 and Na2—′NHS′4 and characterized by X-ray structure analysis. In the solid state [Ni(′NHS′4)]2 contains two pseudooctahedral [Ni(′NHS′4)] fragments bridged via thiolate donors, in DMF solution at 110 °C it dissociates into mononuclear entities. The product of the template reaction between [Ni(′S′2)2]2- (′S′2
2- = 1,2-benzenedithiolate) and (BrC2H4)2NH was shown to contain an as yet unidentified by-product in addition to [Ni(′NHS′4)]2. Pure [Ni(′NHS′4)]2 does not react with pyridine, but the template product forms [Ni(Py)2(′S′2)] which has a square planar coordination geometry with the pyridine rings perpendicular to the NiS2N, plane.
Investigation of the template formation of [Ni(′NHS′4)]2 provided evidence that the reaction of [Ni(′S′2)2]2- with (BrC2H4)2NH involves radicals, suggesting a radical chain reaction mechanism.
Übergangsmetallkomplexe mit Schwefelliganden, LXXXV. / Transition-Metal Complexes with Sulfur Ligands, LXXXV.
Authors: Sellmann D. , Schillinger H. , Knoch F. 
Published: March 2015

Ni(II) salts and the tetradentate thioether-thiolate ligand ′S4-C2′2- (= 1,2-bis(2-mercaptophenylthio)ethane(2-)) yield [Ni(′S4-C2′)]x (1), that also forms when Na2[Ni(′S2′ )2] (′S2
2-′ = o-benzenedithiolate(2-)) is alkylated by 1,2-dibromoethane. In boiling pyridine 1 adds two solvent molecules and gives pseudooctahedral [Ni(pyr)2(′S4-C2′ )] (2) which was characterized by X-ray structure determination. Reaction of 1 with PMe3 yields [Ni(PMe3)(′S4-C2′)] (4). X-ray structure determination of 4 showed that the Ni center is surrounded by one P and four S atoms in a distorted tetragonal pyramid in which the P atom, one thioether S atom and both of the thiolate S atoms form the base while the second thioether S atom occupies the apical position. Reaction of 1 with n-BuLi leads to removal of the C2H4 bridge of the ′S4-C2′2- ligand and formation of Li2[Ni(′S2′)2].
When [Ni(acac)2]3 is reacted with ′buS4-C2′2 (= 1,2-bis(3,5-ditertiarybutyl-2-mercaptophenylthio)ethane(2-)) which is analogous to ′S4-C2′2-, the trinuclear [Ni(′buS4-C2′)]3 (3) forms. 3 · THF was characterized by X-ray structure determination. It contains one tetrahedrally distorted and two planar [NiS4] cores that are connected via the C2H4 groups of the ligands such that a macrocycle forms. PMe3 cleaves 3 to give mononuclear [Ni(PMe3)(′buS4-C2′)] (5). Due to its lability, it was characterized only by spectroscopic methods.
Synthesis, Spectroscopic and X-Ray Structural Characterization of [Cd(linpen)]2+, a Model for Metal Complexes of the Chelating Polymer Polyethyleneimine (linpen = Linear Pentaethylenehexamine)
Authors: Strasdeit Henry 
Published: March 2015

The isolation of 3,6,9,12-tetraazatetradecane-1,14-diamine (linear isomer of pentaethylenehexamine, linpen) from a technical polyamine mixture is described. In methanol, linpen acts as a hexadentate ligand towards cadmium(II). The solid compounds [Cd(linpen)](BPh4)2 (1), [Cd(linpen)](BPh4)2•2 DMSO (2) and [Cd(linpen)](BF4)2 (3) have been isolated and characterized by elemental analysis, spectroscopy and X-ray powder diffraction. The 113Cd NMR resonance of 1 is at 351 ppm (0.30 M in DMSO-d6, standard: 0.10 M Cd(ClO4)2 in D2O).
2 and 3 have been structurally characterized by single-crystal X-ray diffraction. 2: C 2/c; a = 19.337(1)Å, b = 17.937(1)Å, c = 18.584(1)Å, β = 111.54(1)°; Z = 4, R = 0.034, Rw = 0.033.3: P21/n; a = 8.607(1)Å, b = 14.851(2)Å, c = 15.703(2)Å, ß = 91.21(2)°; Z = 4,R = 0.083, Rw = 0.072. Both compounds contain discrete [Cd(linpen)]2+ complexes. The hexamine wraps around the metal ion in a helical manner. This results in a strong distortion of the coordination polyhedron. The mean Cd-N bond lengths are 2.38Å and 2.37Å for 2 and 3, respectively.
Models for MN6 centers in metal-polyethyleneimine (PEI) complexes are derived from the structure of [Cd(linpen)]2+. For example, loops at the MN6 site in molecules of linear PEI are proposed.
Übergangsmetallkomplexe mit Schwefelliganden, XCl+ Fell-Komplexe des fünfzähnigen Thioether-Thiolat-Aminliganden ′buNHS4′-H2: Synthese, Charakterisierung, Reaktivität und Stereochemie (′buNHS4′-H2 = 2,2′-Bis(2-mercapto-3,5-di-tertiärbutyl-phenylthio)diethylamin) / Transition Metal Complexes with Sulfur Ligands, XCI+ Fell Complexes of the Pentadentate Thioether-Thiolate-Amine Ligand ′buNHS4′-H2: Synthesis, Characterization, Reactivity and Stereochemistry (′buNHS4′-H2 = 2,2′-Bis(2-mercapto-3,5-di-tertiarybutyl-phenylthio)diethylamine)
Authors: Sellmann Dieter , Soglowek Wolfgang , Moll Matthias 
Published: March 2015

In search of model compounds for the active centers of nitrogenases, [Fe(L)(′buNHS4')] complexes of the pentadentate thioether-thiolate-amine ligand ′buNHS4'2- (′buNHS4'-H2 = 2,2′-bis(2-mercapto-3,5-di-tertiarybutyl-phenylthio)diethylamine) were obtained.
Alkylation of′buS2'-H2 with (BrC2H4)2NH yielded the new ligand ′buNHS4'-H2 as a mixture of positional isomers. Isolation of single isomers was achieved by reacting the mixture with FecL2•4H2O and CO in order to give the corresponding [Fe(CO)] complexes which were separated and hydrolyzed to yield the free ligands.
Reaction of'buNHS4'-H2 with FeCl2•4H2O led to the high-spin complex [Fe(′buNHS4')] which is extremely air-sensitive in solution. It rapidly reacts with L = CO, NO, PMe3, and N2H4, and is the most suitable starting material for syntheses of [Fe(L)(′buNHS4')] complexes which were characterized for L = CO, NO+, NO, PMe3 and N2H4. All complexes are considerably better soluble in organic solvents than the corresponding parent compounds [Fe(L)(′NHS4')], (′NHS4'-H2 = 2,2′-bis(2-mercaptophenylthio)diethylamine), but have similar properties in most other respects. In the oxidation of [Fe(N2H4)(′buNHS4')] at low temperatures, there is evidence for the formation of the diazene complex [μ-N2H2{Fe(′buNHS4')}2].
Strukturvarianten des MgCu2-Typs: Die Verbindungen Mg2Ni3P und Mg2Ni3As / Variants of the MgCu2 Type: The Compounds Mg2Ni3P and Mg2Ni3As
Authors: Keimes Viktor , Mewis Albrecht 
Published: March 2015

The compounds Mg2Ni3P and Mg2Ni3As were prepared by heating the elements. Their structures have been determined from single-crystal X-ray data. The structure of the phosphide is a rhombohedral ternary variant of the cubic Laves structure type MgCu2 (R 3̄ m; hexagonal lattice constants: a = 4.971(0) Å, c = 10.961(2) Å). The ordered substitution of one quarter of the metal atoms by phosphorus and the resulting shorter distances are responsible for the rhombohedral symmetry.
The arsenide crystallizes in the MgCu2 type structure (Fd 3 m; a = 6.891(1)A, composition Mg2Ni3As) with a statistic distribution of the Ni and As atoms; the relevant homogeneity range extends from Mg2Ni2.9As1.1 to Mg2Ni3.5As0.5.
Übergangsmetallkomplexe mit Schwefelliganden, XC Synthese, Säure/Base- und Redoxreaktionen von [Ni(′N2H2S2′)]: auf der Suche nach Modellkomplexen für die Nickelzentren in Hydrogenasen und CO-Dehydrogenasen. (′N2H2S2′′2- = 1,2-Ethandiamin-N,N′-bis(2-benzolthiolat)(2–)) / Transition Metal Complexes with Sulfur Ligands, XC. Synthesis, Acid Base and Redox Reactions of [Ni(′N2H2S2′)]: A Search for Model Complexes for the Nickel Sites in Hydrogenases and CO-Dehydrogenases. (′Ν2Η2S2
′2- = 1,2-Ethanediamine-N,N′-bis(2-benzenethiolate)(2-))
Authors: Sellmann Dieter , Prechtel Werner , Knoch Falk , Moll Matthias 
Published: March 2015

[Ni(′N2H2S2′)], 1, forms from Ni(II) salts and the tetradentate thiolate-amine ligand ′N2H2S2
′2- (= 1,2-ethanediamine-N,N′-bis(2-benzenethiolate)(2-)) [2], or by reduction of the Schiff base complex [Ni(gma)] (gma2- = glyoxal-bis(2-mercaptoanilide(2–))) with NaBH4.
Bases easily deprotonate 1 to yield the [Ni(′N2S2′)]2- dianion, which is extremely easily oxidized to give the Ni(II) monoanion [Ni(′N2S2′)]- which was isolated as [AsPh4][Ni(′N2S2′)], 4, and characterized by X-ray structure analysis. 4 contains a distorted square planar NiN2S2 core, in which two thiolate-S and two amido-N donors are surrounding the nickel atom.
Deprotonation of 1 was further substantiated by H*/D+ exchange to give [Ni(′N2D2S2′)] and by alkylation. Consecutive reaction of 1 with n-BuLi and CH3I leads to fourfold methylation of 1 yielding [Ni(′N2Me2S2Me2′)I2], 8, while alkylation of 1 by CH3I in the absence of base yields [Ni(′N2H2S2Me2′)I2], 5, in which only the thiolate donors have been alkylated. X-ray structure analysis shows 8 to contain a distorted octahedral NiN2S2I2 core with two sulfur atoms occupying axial trans positions and two nitrogen and two iodine atoms occupying equatorial cis positions. 1 also forms by reaction of [Ni(CO)4] with ′N2H2S2′-H2, which is explained by a series of oxidative addition and reductive elimination reactions.
Palladium and platinum homologues [Pd(′N2H2S2′)], 9 and [Pt(′N2H2S2′)], 10, were synthesized from [MC12(COD)] (M = Pd, Pt) and ′N2H2S2′-H2, and exhibit analogous reactivity as 1.
Spectroscopic and X-Ray Investigation of Cobalt(III) Complexes with 2-Oximinocarboxylic Acids
Authors: Lampeka Rostislav D. , Uzakbergenova Zamira D. , Skopenko Victor V. 
Published: March 2015

Mixed complexes of Co(III) with 2-oximinopropionic (H2A) or 2-oximino-3-phenylpropionic (H2B) acid and different amine (imidazole, benzimidazole, pyridine, β-picoline, γ-picoline) are reported. Characterization of the complexes was based upon elemental analysis, conductivity and JR, 1H NMR, and electronic absorption spectra, and X-ray diffraction analysis. The organic ligands behave as O,N donors via the carboxyl oxygen and the oxime nitrogen atoms. A trans-octahedral structure has been assigned to the bis(2-oximinocarboxylato)bis(amine)cobalt(III) on the basis of 1H NMR data.
The crystal and molecular structures of the complexes trans-[bis(2-oximinopropionato)bis-(imidazole)]- (I) and trans-[bis(2-oximinopropionato)bis(pyridine)]cobalt(III) (II) were determined. I crystallizes in space group P2/n with a = 14.1 67(2), b = 8.774(1), c = 14.785(2) Å,β = 113.37(1)°, Z = 4, Dcalc = 1.568 g · cm-3. II crystallizes in space group P1̄ with a = 9.122(2), b = 10.038(2), c = 11.759(2) Å, α = 69.95(1)°, β = 67.47(2)°, γ = 69.49(2)°, Ζ = 2, Dcalc = 1.547 g cm-3. The structures were refined to unweighted R factors of 0.036 and 0.028, respectively. The coordination sphere around Co is pseudo-octahedral with the 2-oximinopropionato ligands occupying four equatorial positions, and the amines in axial positions.
Oligophosphan-Liganden, XXXVIII / Oligophosphine Ligands, XXXVIII
Authors: Becker Corinna , Dahlenburg Lutz , Kerstan Sabine 
Published: March 2015

Intermolecular activation of carbon-hydrogen bonds has been accomplished by reduction with sodium amalgam of (sip3)(Me3P)RuCl2, 1, [“sip3” = MeSi(CH2PMe)2)3] in aromatic hydrocarbons, such as benzene and substituted derivatives thereof. In these reactions, the 16e equivalent (sip3XMe3P)Ru(O) thus generated exhibits a preference for insertion across the unhindered metaand para-C-H bonds to produce complexes of composition (sip3)(Me3P)RuH(C6H3RR′) [R = R′ = H, 2; R = H, R′ = CH3, 3; R = R′ = CH3 (3,4-xylyl), 4; R = R′ = CH3 (3,5-xylyl), 5; R = H, R′ = CF3, 6], of which 3, 4, and 6 were isolated as mixtures of meta/para-isomers and Ru-aryl rotamers, respectively. Reaction of the phenyl hydride 2 with 4-MeC6H4NCE (E = O, S) leads to insertion of the heteroallenes into the Ru-Η bond to give (sip3)(Me3P)Ru[N(C6H4Me-4)C(O)H]C6H5, 8, and (sip3)(Me3P)Ru[SC(=NC6H4Me-4)H]C6H5, 10, as the primary products. While the latter forms (sip3)

, 11, by loss of PMe3, the former reacts with another molecule of isocyanate to afford the acyl compound (sip3)

9, as the ultimate product. Treatment of 2 with CO2 results in the formation of a carbonato derivative, (sip3)(Me3P)Ru(O2CO), 7.
•
Übergangsmetallkomplexe mit Schwefelliganden, XCVIII / Transition Metal Complexes with Sulfur Ligands, XCVIII
Authors: Sellmann Dieter , Ruf Richard 
Published: March 2015

Depending on the H+ concentration and solvent, reaction of [RuCl3(NO)(PPh3)2] with 'S2N2H2
′2-- alternatively yields either [Ru(NO)PPh3(′S2N2H2′)]Cl 1 or [Ru(NO)(′S2N2H′)]2 2. 1 gives 2 upon treatment with base, 2 yields 1 when reacted with HC1 and PPh3 in THF. In MeOH, 2 is completely insoluble, but reacts with HC1 to give [Ru(NO)(′S2N2H2′)]2Cl2, 4a, which is converted into [RuCl(NO)(′S2N2H2′)] 3 when dissolved in THF.
Reactions of 2 with phosphines such as PMe3, PPr3 or PBu3 in THF yield the corresponding [Ru(NO)PR3(′S2N2H′)] complexes, which is proof that not a protonation of the amido donor in 2, but sufficient solubility of 2 in the respective solvent and a subsequent dissociation into mononuclear complex fragments are decisive for cleavage of 2. Protonation or deprotonation of the N donors are more likely to influence the fine-tuning of the Ru center in [Ru(NO)(′S2N2H2′)] fragments with respect to coordination of hard or soft co-ligands.
Neue Synthesen mit Magnesiumhydrid Teil 1: Hydromagnesierung von α-Olefinen zu Dialkylmagnesiumverbindungen / New Syntheses with Magnesium Hydride Part 1: Hydromagnesiation of α-Olefines to Magnesium-dialkyls
Authors: Knott Wilfried , Klein Klaus-Dieter 
Published: March 2015

The addition of highly active magnesium hydride to α-olefines, hydromagnesiation, is a well known reaction.
The use of cheap magnesium hydride exhibiting a lower reactivity is highly desirable for industrial purposes.
In a combination of chemical and mechanical activation the low reactivity of high temperature magnesium hydride could be overcome thereby making a broad variety of magnesium alkyls accessible.
Eine unerwartet stabile Sulfensäure: 4,6-Dimethoxy-1,3,5-triazin-2-sulfensäure; Synthese, Eigenschaften, Molekül- und Kristallstruktur / Unexpectedly Stable Sulfenic Acid: 4,6-Dimethoxy-1,3,5-triazine-2-sulfenic Acid; Synthesis, Properties, Molecular and Crystal Structure
Authors: Tripolt Robert , Belaj Ferdinand , Nachbaur Edgar 
Published: March 2015

4,6-Dimethoxy-1,3,5-triazine-2-sulfenic acid (1) was prepared by the reaction of 4,6-dimethoxy-1,3,5-triazine-2(1H)-thion (3) with 2-benzenesulfonyl-3-(p-nitrophenyl)-oxaziridine (2) in THF solution and isolated as a stable crystalline solid. The new compound was characterized by analytical and spectroscopic data (IR, 1H and 13C NMR, UV, MS) supported by MNDO-PM 3 calculations. UV spectrometry was used for exact determination of the ionization constant of 1(pKa = 5.86 ± 0.02 at 20°C). According to 13C NMR data and X-ray analysis the sulfenic acid 1 adopts the sulfenyl structure (R—SOH) in the condensed phase.
Crystal data of 1 (90 K): a = 8.418(3), b = 21.289(6), c = 4.411(1) Å, Z = 4, P 21212, R = 0.0304, Rw = 0.0354 for 4105 unique reflections and 122 parameters. In the crystal, the molecules form dimers by two strong intermolecular O—H ••• N hydrogen bonds. The 6-membered ring shows alternating C—N bond lengths and is almost planar. The experimental electron deformation density (EDD) decreases in the order C—N &gt; C—O ≈ C—S &gt; S—O and is described in detail for the vicinity of the S atom.