bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorescein-Photosensitized Furan Oxidation in Methanolic and Reversed Micellar Solutions, Part I. Effects of Amines
Authors: Miyoshi Norio , Tomita Giiti
Published: February 2015

The 1,3-diphenylisobenzofuran oxidation reaction was investigated in methanolic and dodecylammonium propionate reversed micellar solutions using fluorescein sodium as photosensitizer. It was found that aniline remarkably enhanced the furan oxidation in methanolic solutions but inhibited it in reversed micellar solutions. This enhancement effect occurred more effectively at lower oxygen concentrations. It was proposed that, in the former solutions, the radical mechanism (Type I) might be involved in the furan oxidation in the presence of aniline besides singiet oxygen mechanism (Type II). The reversed micelle seems to inhibit the Type I reaction, resulting in no enhancement of the furan oxidation by aniline.
Die P2O7-Schwingungen in Thiamin-Diphosphat / The P2O7 Vibrations in Thiamine Diphosphate
Authors: Baran E. J. , Etcheverry S. B.
Published: February 2015

The infrared P2O7 and COP vibrations of thiamine diphosphate tetrahydrate have been assigned by comparison with related species.
Darstellung und Kristallstruktur von (PPh3)3Ag2WS4, einem neuartigen Dreikern-Komplex mit tetraedrisch und trigonal planar koordinierten Ag-Atomen / Preparation and Crystal Structure of (PPh3)3Ag2WS4, a Novel Trinuclear Complex with Tetrahedral and Trigonal Planar Coordination of the Ag Atoms
Authors: Müller Achim , Bögge Hartmut , Königer-Ahlborn Elisabeth
Published: February 2015

The title compound was prepared by reaction of AgNO3, P(C6H5)3 and (NH4)2WS4 in a dichloromethane/water system. The crystal structure was determined from single crystal X-ray diffraction data (monoclinic, space group P21/c, with a = 1811,1(2), b = 1735.6(2), c = 1779,7(2) pm, β = 95,02(1)°, V = 5572,7 · 106 pm3, Z = 4). The compound contains a tetradentate WS4
2- ligand and two silver atoms, having a tetrahedral and trigonal planar coordination.
Darstellung, Struktur und Eigenschaften einer neuen Modifikation von NbI5 / Preparation, Structure and Properties of a New Modification of NbI5
Authors: Krebs Bernt , Sinram Diethard
Published: February 2015

Triclinic niobium(V) iodide was prepared from the elements at an iodine pressure of 3-4 bar in a temperature gradient from 400 to 230 °C. It crystallizes in the space group P1̄ with a = 7.591(3), b = 10,322(3), c = 6.977(3) Å, α = 90.93(3), β = 116.17(3), γ = 109.07(3)°, Z = 2 Nbls. The single-crystal X-ray structure analysis shows the compound to contain dimeric Nb2I10 molecules with Nb-I bond lengths of 2.933 and 2.939(1) A for the bridge bonds and of 2.639···2.720(1) Å for the terminal bonds. The structure is isotypic with triclinic β-UCl5. The infrared spectrum indicates stretching vibrations at 148, 202, 214 and 242 cm-1 .
29Si-Kernresonanzuntersuchiingeii an Polysilanen 1. Perchlorpolysilane / 29Si NMR Investigations on Polysilanes 1. Perchloropolysilanes
Authors: Marsmann H. C. , Raml W. , Hengge E.
Published: February 2015

Several oligomeric perchloro silanes of the type Cl2n+2Sin (n= 1 to 6) were studied by 29Si NMR. n-Cl12Si5 was synthesized for the first time. Structures of isomeric silanes could be determined by substituent effects.
Die Spaltung von Tetrahydrofuran mit Trimethylchlorsilan und Dialkylantimoniodid / Cleavage of Tetrahydrofurane by Trimethylchlorosilane and Dialkylantimonyiodide
Authors: Breunig Hans Joachim , Breunig-Lyriti Vassiliki
Published: February 2015

In the reaction of dimethyl- and diethylantimony iodide with magnesium, trimethylchlorosilane and tetrahydrofurane the new compounds 1-dimethyl- and diethylstibino- 4-trimethylsiloxibutane 1, 2 are produced. The reactions of dimethyl- and diethylantimony bromides with magnesium in THF in the presence of trimethylchlorosilane only yield the corresponding distibanes.
Reaktionen koordinierter Liganden, VI [1] Substituenteneinflüsse bei der Bildung von Tri- und Tetraphosphinen in der Koordinationssphäre von Übergangsmetallen / Reactions of Coordinated Ligands, VI [1]. Influence of Substituents on the Formation of Tri- and Tetraphosphines in the Coordination Sphere of Transition Metals
Authors: Stelzer Othmar , Weferling Norbert
Published: February 2015

The lithiumphosphido complex cis-Mo(CO)4(Me2PLi)2 reacts with dichlorophosphines RPCl2(R = Ph, But) to give coordination compounds of tetraphosphines Me2P-PR-PR-PMe2, whereas the complex of the triphosphine cis-Mo(CO)4 (Ph2P-PMe-PPh2) is obtained starting with the lithiumphosphido complex cis-Mo(CO)4(Ph2PLi)2. Phenyldilithiumphosphine and the chlorophosphine complexes cis-Mo(CO)4(R2PCl)2 (R = Me, Ph) give in low yield cis-Mo(CO)4(R2P-PPh-PPh-PR2) and cis-Mo(CO)4(R2P-PPh-PR2). The mechanisms of these reactions are discussed. The {31P}1H- and {1H}31P-NMR spectra are analysed and correlated with the structures of these complexes.
Übergangsmetall-Carbin-Komplexe, LVI [1]. Umsetzung eines kationischen Carbin-Komplexes mit einem Carbonylmetallat. Der Phenylketenyl-Rest als Briickenhgand / Transition Metal Carbyne Complexes, LVI [1]. Reaction of a Cationic Carbyne Complex with a Carbonylmetalate. The Phenylketenyl Group as a Bridging Ligand
Authors: Orama Olli , Schubert Ulrich , Kreißl Fritz Roland , Fischer Ernst Otto
Published: February 2015

By reaction of [(π-H5H5)(CO)2Mn≡C-C6H5]BCl4 with NaRe(CO)5 a new type of complex is obtained. It crystallizes in the monoclinic space group P21/c, Z = 4, a - 1115(1), b= 1464(1), c= 1657(2) pm, β= 136.79(8)°. Structure determination reveals a binuclear complex, the Mn-Re bond (281.7(3) pm) of which is bridged by the a-carbon atom of a phenylketenyl group (Mn-C 221(3), Re-C 224(3) pm) and semi-bridged by a CO group (Mn-C 187(4), Re-C 254(4), Mn-C-0 160(3)°).
Studies on Betaine Decomposition of Arsonium Ylides
Authors: Tewari R. S. , Suri S. K. , Gupta K. C.
Published: February 2015

Betaine, Arsonium Ylides A systematic study on the nature of decomposition of betaine formed by nucleophilic attack of semistabilized arsonium ylides on thiocarbonyl substrates has been carried out. A series of substituted benzylidenetriphenylarsenanes have been generated from their corresponding salts and condensed with few cyclic thioketones to yield exocyclic olefins as exclusive products. The non-availability of thioepoxides indicates that the mode of decomposition of such type of betaines is quite analogous to the betaine formed by phosphonium ylides. The structure of the products have been assigned by IR and NMR spectral studies.
Transylidation Reactions in Arsonium Ylides
Authors: Tewari Ram S. , Nagpal Dinesh K.
Published: February 2015

Some substituted benzylidenetriphenylarsenanes have been generated from their precursors and treated with acid chlorides or acid anhydrides to afford intermediate arsonium salts which in the presence of starting ylides undergo transylidation to give carbonyl stabilized arsonium ylides in fair to good yields. The structures of these stabilized ylides were confirmed on the basis of their spectral data.
Hydroxylation of ⊿5-Steroids with N-Bromosuccinimide to 5α,6β-Diols
Authors: Dawidar A. M. , Saleh A. A. , Abdel-Malek M. M.
Published: February 2015

The reaction of N-bromosuccinimide with ⊿5 -steroids such as, diosgenin, cholesterol, stigmasterol and dehydroisoandrosterone were studied. It was found that NBS in a solvent mixture of acetone, water and acetic acid (8:1:0.1) oxidises the olefinic bond of all the previous steroidal compounds to the corresponding transglycollic, 5α,6β-di-hydroxylic products in about 60% yield at room temperature.
X-ray Structural Study of 5-Phenyl-10,11-dihydrodibenzo[b,f]phosphepin-5-oxide
Authors: Allen David W. , Nowell Ian W. , Walker Philip E.
Published: February 2015

Crystals of the title compound are triclinic, a = 8.533(5), b = 11.106(6), c = 8.815(5) Å, a = 107.83(6), β = 104.99(6), γ = 81.30(5)°, Z = 2, space group P1̄. The structure was determined by multisolution direct methods and electron density methods. Refinement by least-squares techniques gave a final R = 0.081 for the 1753 independent reflections. The molecule adopts a butterfly-type conformation such that the fused phenyl rings are inclined to each other at an angle of 56.8°. The P-0 bond distance is 1.506(4) Å; the endocyclic angle at phosphorus is 107.2(3)° and the exocyclic angles vary from 106.5 to 111.9(3)°.
Umsetzungen von Metall- und Metalloidverbindungen mit mehrfunktionellen Molekülen, XXV [1]. Thioureidoborane und Isothioureidoborane / Reactions of Metal and Metalloid Compounds with Polyfunctional Molecules, XXV [1]. Thioureidoboranes and Isothioureidoboranes
Authors: Maringgele Walter
Published: February 2015

N,N',N'-Triorganyl-N-trimethylsilylthioureas react with halogeno diorganyl boranes to yield the N,N',N'-organyl-thioureidoboranes 1-7 and isothioureidoboranes 8-15. 10-15 are intramolecularly associated. The compounds are characterized analytically and spectroscopically (NMR: 1H, 13C, HB; MS; IR).
η3 -Allyl-hydrogensulfidonickel(II)-Komplexe / η3 -Allyl-hydrogensulfidonickel(II) Complexes
Authors: Benn Reinhard , Bogdanović Borislay , Göttsch Peter , Schlichte Klaus
Published: February 2015

Bis(η3-allyl)- or bis ( η3 -2-methylallyl )nickel react with hydrogensulfide at -78 °C to give in high yields the dimeric di-μ-hydrogensulfido-bis(η3-allyl)dinickel(II) (2) or di-μ-hydrogensulfido- bis(η3-2-methylallyl)dinickel(II) (2a), respectively, which decompose above 20 °C to give nickelsulfide and propene or isobutene. From bis(η3-allyl)nickel and deuterium sulfide, the di-μ-deuteriumsulfido-bis(η3-allyl)dinickel(II) was obtained. The high resolution 1H NMR spectra reveal the existence of three stereoisomers of 2 or 2 a to which the structures c, d and e have been assigned. The high resolution 1H NMR spectrum of η3-allyl-hydrogensulfido(trimethylphosphine)nickel(II) (3) at -100 °C is consistent with a square planar structure; above -100 °C an equilibration process between syn-, syn- and anti-, anti-protons occurs and above - 20 °C equilibration of syn- and anti-protons of the η3-allyl group is observed.
Methyl-Eliminierung aus dem metastabilen Homoadamantan-Radikalkation / Methyl Loss from Metastable Homoadamantane Cation Radical
Authors: Schwarz Helmut , Wesdemiotis Chrysostomos , Weiske Thomas , Schwarz Helmut , Wesdemiotis Chrysostomos , Weiske Thomas
Published: February 2015

It is demonstrated that methyl loss from ionized homoadamantane (1) yields exclusively the 1-adamantyl cation (4); there is no experimental evidence for the formation of the secondary adamantyl cation (5). From both model calculations and the investigation of [4-13C]-homoadamantane (1a) and 1(13C-methyl)adamantane (2a) it is concluded, that 24% of the metastable homoadamantane cation radicals dissociate after one isomerization (1→2); the remaining 76% are able to undergo at least a second (degenerate) isomerization cycle (2→1→2) prior to methyl loss. 78% of metastable 1-methyl-adamantane cation radical, obtained upon direct ionization of the corresponding neutral hydrocarbon, dissociate directly, whereas the loss of methyl from the remaining 22% is preceded by an isomerization 2 →1 →2.
Pyrolysis Mass Spectrometry of Protected Phosphotriester Oligodeoxyribonucleotides
Authors: Ulrich J. , Bobenrieth M. J. , Derbyshire R. , Finas F. , Guy A. , Odin F. , Polverelli M. , Téoule R.
Published: February 2015

Pyrolysis mass spectrometry is shown to be a useful tool in the analysis of the protected intermediate deoxy oligonucleotides synthesized by the phosphotriester approach. Characteristic ions of the protected nucleic acid bases and terminal substituents appear in the mass fragmentation pattern which allows a rapid control of the attachment of the polynucleotide block in the chemical synthesis.
Alkaloide in Tabernaemontana-Arten, XI [1]. Untersuchung der Alkaloide von Tabernaemontana quadrangularis — (20R)-20-Hydroxyibogamin, ein neues Alkaloid aus T. quadrangularis / Alkaloids in Tabernaemontana Species, XI [1]. Investigation of the Alkaloids from Tabernaemontana quadrangularis — (20R)-20-Hydroxyibogamine, a New Alkaloid from T. quadrangularis
Authors: Achenbach Hans , Raffelsberger Bernd
Published: February 2015

From the methanolic extract from the roots of T. quadrangularis we isolated 14 alkaloids (1-14) and deduced their structures. All the alkaloids are of the ibogamine-type or im-mediately related to it; (20R)-20-hydroxyibogamine (5) was found for the first time as a natural product.
Alkinylverbindungen von Übergangsmetallen, XXXVIII [1]. Komplexe Mangan(II)-Verbindungen des 1.2-Diethinylbenzols / Alkynyl Compounds of Transition Metals, XXXVIII [1]. Complex Manganese(II) Compounds of 1,2-Diethynylbenzene
Authors: Nast Reinhard , Santos Amelia
Published: February 2015

The high-spin d5 complexes M2Mn(1,2-C6H4(C≡C)2)2 (M = K, Na) are prepared in liquid ammonia according to equation (1). The magnetic moment and the position of the IR-active υC ≡ C of the potassium salt are discussed with respect to the structure of the solid compounds.
Die Kristallstruktur des Tl10Hg3Cl16 / The Crystal Structure of Tl10Hg3Cl16
Authors: Brodersen Klaus , Jensen Klaus-Peter , Thiele Gerhard
Published: February 2015

The structure of Tl10Hg3Cl16 (tetragonal; space group I4/m; a - 849,0(2) pm, c = 2372,9(6) pm) was determined by X-ray structure analysis. This compound consists of HgCl4 tetrahedra and linear Cl-Hg-Cl units, which are completed by four additional chlorides to distorted (2 + 4) HgCl6 octahedra. A close relationship to the Tl4HgX6 structure (X = Br, I) is discussed.
1.3-Silylgruppenwanderung im Si2NSiN-Gerüst - Synthese und Molekülstruktur von 1.3-Diaza-2.4-disilacyclobutanen / 1,3-Migration of Silylgroups in the Si2NSiN-System - Synthesis and Molecular Structure of 1,3-Diaza-2,4-disilacyclobutanes
Authors: Clegg William , Klingebiel Uwe , Krampe Cornelia , Sheldrick George M.
Published: February 2015

N-Organylamino-N′,N′-bis(trimethyl)amino-fluoroorganylsilanes react with butyl-lithium to give the corresponding lithium salts. Further reaction of these lithium salts with fluorosilanes leads to the formation of the expected substituted compounds. Diaza-disilacyclobutanes are formed by thermal LiF elimination in THF. The simultaneous 1,3-migration of a trimethylsilyl group from one nitrogen atom to another is demonstrated by the crystal structure determination of the products of two such reactions, with different substituent groups.
Darstellung, Schwingungsspektrum und Kristallstruktur des Decabromo-μ-nitrido-ditantalats(V) Ta2NBr10
3-. Ein Komplex mit symmetrischer Ta=N = Ta-Brücke / Preparation, Vibrational Spectra and Crystal Structure of the Deca Bromo μ-Nitrido Ditantalate(V) Ta2NBr10
3-.A Complex with a Symmetrical Ta=N=Ta Bridge
Authors: Frank Klaus-Peter , Strähle Joachim , Weidlein Johann
Published: February 2015

The salt (NH4)3Ta2NBr10 can be prepared from NH4Br und TaBr5 at 400 °C in a sealed glas ampoule. The greenish yellow substance, which is sensitive to moist air, crystallizes in the tetragonal space group P4/mnc with Z = 2. The crystal structure is closely related to that of K4M2OCl10 · H2O (M = Ru, Re). It is built up by NH4
+ cations and Ta2NBr10
3-- anions. The anions possess the point symmetry D4h and therefore show a symmetrical Ta = N = Ta bridge. The Ta-N distances of 185 pm can be interpreted by double bonds.
Borchelate und Bormetallchelate, VI [1] Zur Bildung von Borchelaten aromatischer Azoverbindungen / Boron Chelates and Boron Metal Chelates, VI [1]The Formation of Boron Chelates of Aromatic Azo Compounds
Authors: Hohaus Eberhard , Wessendorf Klaus
Published: February 2015

Bidentate chelate reagents incorporating a suitable group (e.g. OH, NH2) in ortho position to the azo-group react with diphenylboronic acid anhydride or boron trihalides (BF3, BCl3) resulting in the BR2-six membered ring-chelates of types 1 and 2.

The products of the reaction of tridentate chelate reagents with phenylboronic acid or boron trifluoride at elevated temperature are BR-chelates with two six membered rings (types 3 and 4).

The conditions of the formation of the bicyclic chelates 5 and 6 depend on the position of the substituents of the chelate reagents.

The incorporation of only one BR2 group is possible if the order of the substituents in 2,2′-dihydroxyazobenzenes is not symmetrical (chelates of the type 7).

Structural isomers of boron chelates of the types 5, 6 or 7 with Nα/Nβ isomerism have not yet been observed. The identification of the structures of the above-mentioned complexes was achieved by means of 1H, 11B and 19F NMR and IR spectroscopy. For mass spectrometric analysis see ref. [2].
A New Preparation of S4N4
Authors: Berthet M. P. , Vincent H. , Monteil Y.
Published: February 2015

Pure S4N4 is prepared by a new method from reduction of S3N3Cl3 by various metals (Hg, Cu, Sn). Realized either in an inert solvent or directly in gaseous phase the reaction is complete. The stability range of NSCl has been determined by Raman spectrometry.
Structural Change of a Line ar Polyether upon Complex Formation. 1.11-Bis(2-acetylaminophenoxy)-3.6.9-trioxaundecane and its KSCN Complexa
Authors: Suh Il-Hwan , Weber Gabriela , Kaftory Menachem , Saenger Wolfram , Siegerd Heinz , Vögtled Fritz
Published: February 2015

The title compound (1) was crystallized as free ligand and as its (1 · KSCN)2 · H2O complex. Crystallographic data are, for the former: space group C 2/c, a = 31.110(9), b = 4.608(4), c = 17.188(6) Å, β = 105.27(8)°, Z = 2, Dm = 1.25 gem-3; for the latter: space group P21, a = 11.044(3), b = 18.310(4), c = 14.485(4) Å, β = 97.49(2)°, Z = 4, Dm = 1.27 gem-3. Crystal structures were solved by direct methods using X-ray diffraktometer data and least squares refinements converged at 10.8% for 1 and at 7.6% for (1 · KSCN)2 · H2O.

The free ligand (1) is S-shaped and, upon K+-complexation, changes signs of some gauche O-C-C-O torsion angles while C-C-O-C angles remain trans. In (1 · KSCN)2 · H2O, there are two complex molecules 1 A · KSCN · H2O (I) and 1 B · KSCN (II). The ligands are wrapped circularly around K+ and coordinated with only four of the five polyether oxygens. K+ interacts further with H2O in (I) and with N of SCN- in II and, in both complexes, with acetylamino oxygen of adjacent 1. The latter interaction leads to polymeric structures not observed previously for similar complexes.
Reaktivität metallorganischer Komplexe mit Zinn-Metall-Bindung, IV [1]. SO2 -Insertion an phosphinsubstituierten und anionischen Triorganozinn-Komplexen des Chroms, Molybdäns und Wolframs / Reactivity of Organometallic Complexes Containing Tin-Metal Bonds, IV [1]. SO2 Insertion into Phosphine Substituted and Anionic Triorganotin Complexes of Chromium, Molybdenum and Tungsten
Authors: Kunze Udo , Sastrawan S. Budhi
Published: February 2015

The trans phosphane and phosphite substituted organotin complexes of molybdenum 1-4 are prepared by thermolysis or photolysis of the tricarbonyl parent compounds. The phosphane complexes 1 and 2 react readily with liquid sulfur dioxide by absorption of 1-3 moles of SO2 depending on temperature. IR and NMR spectra indicate cleavage of tin-carbon bonds only yielding insertion products of the sulfinato-O type 1a-c and 2a-c. The phosphite complexes 3, 4 are less reactive and yield a di-insertion 3a and a mono-insertion compound 4a. The anionic triphenyltin derivatives of chromium, molybdenum and tungsten 5-7 undergo facile cleavage of 1 (Cr) or 3 (Mo, W) tin-phenyl bonds. The course of SO2 insertion into 1-7 reveals a distinct activation of the Sn-C bond in organotin transition metal complexes by substitution with stronger donor molecules or reduction to anionic species.
Vergleich zwischen 11B-und 13C-chemischen Verschiebungen dreifach koordinierter Borverbindungen und Carbenium-Ionen / Comparison between 11B and 13C Chemical Shifts of Three-Coordinate Boron Compounds and Carbenium Ions
Authors: Wrackmeyer Bernd
Published: February 2015

The relationship between 11B chemical shifts (δ11B) of trigonal boranes and 13C⊕ chemical shifts (δ13C⊕) of carbenium ions was found to be more complex than previously reported. The trends observed allow for the comparison of (pp) n bonding between boron and suitable substituents with the π-charge derealization in carbenium ions. In case of the ferrocenyl boranes and ferrocenyl carbenium ions the markedly different trend in the shielding of 11B and 13C⊕͵ favours a fulvene-like structure for the substituted cyclopentadienyl ring in the latter. Structural features are analogously reflected by δ11B and δ13C⊕ data for both series of compounds. Comparison of δ13C data of organoboranes and carbenium ions can be useful in conformational studies.
The Recombination Luminescence of Tryptophan in Aqueous Glasses, I. Quenching Effect of Electron Scavengers
Authors: Yamashita Shozi , Tomita Giiti
Published: February 2015

The quenching effect of SeO4-- and NO3- (scavenger for trapped electrons) on the delayed luminescence (‘recombination luminescence’) caused by the recombination of trapped electrons with mother tryptophan cations was investigated in aqueous 9 M NaOH and 9.5 M LiCl glasses at 77 K. The results show that the trapped electrons responsible for the recombination fluorescence were deep-trapped ones in 9 M NaOH glasses and shallowand deep-trapped ones in 9.5 M LiCl glasses. However, trapped electrons participating in the recombination phosphorescence were almost shallow-trapped ones in the two glasses. The distribution of the trapped electrons is discussed.
Sila-Pharmaka, 16. Mitt. [1]. Sila-Analoga von Nifedipin-ähnlichen 4-Aryl-2.6-dimethyl-1.4-dihydropyridin-3.5-dicarbonsäure-dialkylestern, I. / Sila-Drugs, 16th Communication [1]. Sila-Analogues of Nifedipine-Like Dialkyl 4-Aryl-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylates, I.
Authors: Tacke R. , Bentlage A. , Towart R. , Meyer H. , Bossert F. , Vater W. , Stoepel K.
Published: February 2015

The nifedipine-like 1,4-dihydropyridines 10a and 11a as well as their sila-analogues 10b, 10c, and 11b were synthesized for the first time. 10a, 10b, 10c, 11 a , 11b , and their precursors 8a, 8b, 9a, and 9b were characterized by their physical and chemical properties, and their structures confirmed by analyses, 1H NMR and mass spectroscopy. The antispasmodic, vasodilating, and antihypertensive properties of 10a, 10b, 10c, 11a, and 11b were compared.
Beiträge zur Chemie des Phosphors, 96 [1] Darstellung und 31P-Kernresonanzspektrum von isotopen-substituiertem Trilithium-heptaphosphid, 6Li3P7 / Contributions to the Chemistry of Phosphorus, 96 [1] Preparation and 31P NMR Spectrum of Isotopicly Substituted Trilithiumheptaphosphide, 6Li3P7
Authors: Baudler Marianne , Pontzen Thomas , Hahn Josef , Ternberger Hans , Faber Wolfgang
Published: February 2015

The P7-skeleton of trilithiumheptaphosphide, Li3P7 (1), was proved to possess the earlier reported tricyclic structure [2] by complete analysis of the 31P NMR spectrum of 6Li3P7 observed at - 60 °C. The 6Li isotopic substitution was carried out to avoid the line broadening caused by the large quadrupole moment of the 7Li isotope. The unambiguous elucidation of the Li3P7 structure confirmed that the exchange process which causes all P atoms to become equivalent above room temperature is analogous to that in bullvalene. A comparison of the chemical shifts with those of (Me3Si)3P7 leads to the result that the P7-skeleton in Li3P7 is noticeably compressed along its threefold axis, thus indicating a predominant ionic character.
Vereinfachte Synthese und Reaktionen von Selenocarbonyldifluorid / A Simplified Synthesis and Reactions of Selenocarbonyldifluorid
Authors: Darmadi Alexius , Haas Alois , Koch Bernd
Published: February 2015

SeCF2 is prepared on a preparative scale reacting AII3 with Hg(SeCF3)2 in octamethyl-cyclotetrasiloxane. It adds MF [M = Cs, Tl, [(CH3)4N] and Ag] to form MSeCF3. AgSeCF3 was also synthesized from AgF and B(SeCF3)3. Under the influence of sunlight SeCF2 dissolved in CFCI3 dimerizes quantitatively to 2,2,4,4-tetrafluoro-1,3-diselenetane, which above 360 °C pyrolyses to the monomer. The cyclic dimer reacts with B(SeCF3)3 to give (CF3Se)2CSe. The reaction of AgSeCF3 with CFnCl3-nSCl leads to CF3SeSCFnCl3-n (n = 1, 2, 3). IR, NMR and mass spectra of the newly prepared compounds were presented.
Die Elektrolyse von P4/HS03F-Miscliiingeii / The Electrolysis of P4/HSO3F Mixtures
Authors: Fritz Heinz P. , Huber Otto S.
Published: February 2015

The electrolysis of P4/HSO3F mixtures does not yield detectable phosphorus-polyatomic cations; the intense coloration of the electrolyte is due to the known sulfur polyatomic cations originating from decomposition of HSO3F.
Borierungsreaktionen an den N-Oxiden und -Iminen ungesättigter Stickstoffbasen / Boration Reactions with the N-Oxides and m-Imines of Unsaturated Nitrogen Bases
Authors: Paetzold Peter , Schimmel Günther
Published: February 2015

1,3-Dipolar reagents with an unsaturated CNO- or CNN-skeleton undergo 1,3-organoboration by triorganoboranes. On the other hand, the unsaturated NNO-skeletons in azoxybenzene or nitrous-oxide are reduced to the corresponding NN-fragment by trialkylboranes. The 1,3-addition of aminoborane Cl2BNMe2 to the aldimineoxide PhHC = NMe-0 represents one of the rare examples of analogous reactivity of BN- and CC-double bonds. O-Borylhydroxylamines PhHCR-NMe-OBR2 are reduced by BR′3 to PhHCR-NMe-BR′2 and R′0-BR2. Similar reduction products are isolated from liquid-phase thermolysis of PhHCEt-NMe-OBEt2 (16), whereas gas-phase thermolysis of 16 gives PhCH = NMe, (EtBO)3, and C4H10.
Organometallphosphin-substituierte Übergangsmetallkomplexe, XXVI [1] Diearbonyl-nitrosyl-organometaUphosphin-kobalt-Komplexe / Organometalphosphine-Substituted Transition Metal Complexes, XXVI [1] Dicarbonyl Nitrosjd Organometal Phosphine Cobalt Complexes
Authors: Schumann Herbert , Meissner Manfred
Published: February 2015

The reactions of tricarbonyl nitrosyl cobalt with tri-tert-butylphosphine, di(tert-butyl)-trimethylsilyl-, -germyl-, -stannylphosphine, tert-butyl-bis(trimethylsilyl)-, -(germyl)-, -(stannyl)phosphine, as well as with tris(trimethylsilyl)-, -(germyl)-, and -(stannyl-phosphine result in the elimination of one CO-ligand and the formation of corresponding dicarbonyl-nitrosyl-organometal phosphine cobalt complexes. The NMR spectra of the products are reported and discussed.
Dodecamethyl Bisimidotriphosphoramide (TRIPA) A Tridentate Ligand, Part II [1]
Authors: Lapidaire Johannes C. P. M. , Groeneveld Willem L.
Published: February 2015

In this article we describe the synthesis of TRIPA, dodecamethyl bisimidotriphosphoramide (C12H36N7O3P3) and of its complexes with various lanthanide-nitrates. Five types of complexes have been isolated according to the compositions, X-ray diffraction patterns and IR spectra.

1. M(N03)3(TRIPA)3(acetone) M = La, Pr, Nd,

2. M(N03)3(TRIPA) M = Y,

3. M(N03)3(TRIPA)2(nitromethane) M = Er, Y,

4. M(N03)3(TRIPA)2(acetone) M = Sm, Gd, Dy, Er, Y (type I),

5. M(N03)3(TRIPA)2(acetone) M = Y (type II).

The yttrium complexes, type I and II, are isomeric. IR spectra are given together with the NMR spectra. It is concluded that in all complexes the three TRIPA oxygens are coordinated, except in group 1. The nitrate groups in group 2 to 5 are involved in the coordination, particularly in the type 2 complex, where there are bidentate nitrate groups. There seems to be a difference in the conformation of the TRIPA molecules between the free ligand, the complexes in group 1, in group 2 and in group 3, 4, 5 Hygroscopic TRIPA can be easily confused with a stable mono-hydrate, TRIPA · H2O.
Neue reduzierte Halogenide der Lanthanoide mit kondensierten Clustern: Tb6Br7 und Er6I7 / New Reduced Halides of Rare Earth Metals with Condensed Clusters: Tb6Br7 and Er6I7
Authors: Berroth Karl , Mattausch Hansjürgen , Simon Arndt
Published: February 2015

The new compounds Tb6Br7 and Er6I7 are formed from the trihalides with an excess of metal in sealed tantalum containers. X-ray structure investigations [space group C2/m; Tb6Br7 (Er6I7): a = 2057.1 (2137.5), b = 379.3 (386.9), c = 1180.0 (1231.9) pm, β = 124.59° (123.50°)] show one-dimensional regions connected by Ln-Ln bonds. The structure type can be described in terms of Ln6X12-clusters which are linked via edges of Ln6-octahedra to form double strings. The structure is derived from an FCC arrangement of halogen atoms part of which is systematically substituted by Ln6-octahedra.
NMR-Untersuchungen an Organoelement(IVb)-phosphinen, VI [1] 61Ni-NMR-Untersuchungen an Organoelement(IVb)-phosphin-substituierten Komplexen des Tetracarbonylnickel / NMR Studies on Organoelement(IVb)-phosphines, VI [1] 61Ni NMR Spectroscopic Investigations on Organoelement(IVb) Substituted Complexes of Tetracarbonylnickel
Authors: Schumann Herbert , Meißner Manfred , Kroth Heinz-Jürgen
Published: February 2015

61Ni NMR chemical shifts and 61Ni31P NMR coupling constants are reported for complexes of the type [(CH3)3M]n[tC4H9]3-nPNi(CO)3 (M = Si, Ge, Sn; n = 1, 2, 3) and related to 55Mn and 59Co chemical shifts of the corresponding trinitrosylmanganese and dicarbonylnitrosylcobalt complexes.
Selektive Bulk-Hydrierung von a,β-ungesättigten Ketonen zu Ketonen mit homogenen Ir- und Ru-Katalysatoren / Selective Bulk-Hydrogenation of a,β Unsaturated Ketones to Ketones with Homogeneous Ir and Ru Catalysts
Authors: Strohmeier Walter , Michel Manfred , Weigelt Luise
Published: February 2015

a,β Unsaturated ketones are selectively hydrogenated to ketones in homogeneous bulk-catalysis under mild conditions by iridium-and ruthenium complexes. The range of mean turnover is from 6 to 196 depending on substrate, catalyst and reaction conditions. Selectivity ketone/alcohol depends on the degree of conversion and exceeds 100 on conversion of 90%.
Präparative und röntgenographische Untersuchungen über Cäsium-Silber-Gold(III)-Chlorid/Preparation and X-ray Investigations of Cesium Silver Gold(III) Chloride
Authors: Berthold Hans Joachim , Ludwig Wolfgang
Published: February 2015

Cesium silver gold(III) chloride has been prepared from hydrochloric acid solutions. The composition of the preparations is variable and depends on the ratio [Au(III)]/[Ag(I)] in solution. It corresponds to the formula Cs2Ag1-xAu1+x/3Cl6. In the range 0 ≤ x ≤ 0,64 six crystallographically different phases have been observed. Above x = 0,42 a cubic phase is obtained. The stoichiometric compound Cs2AgAuCl6 is obtained only from solutions with [Au(III)]/[Ag(I)] < 1.

Reports in the literature which claim the stoichiometric compound Cs2AgAuCl6 to exist in a cubic and in a tetragonal form cannot be confirmed. Cs2AgAuCl6 crystallizes orthorhombically with the lattice constants a = 15,21 Å, b = 15,16 Å and c = 10,32 Å (Z = 8).
Übergangsmetall-Methylen-Komplexe, X [1] Methylen-und Alkyl-Eisen-Komplexe aus Diazoalkanen. Molekülstruktur von μ-Carbonyl-μ-tert-butoxycarbonyl-methylen- bis [carbonyl(η5 -cyclopentadienyl)eisen] (Fe-Fe)/Transition Metal Methylene Complexes, X [1] Methylene and Alkyl Iron Complexes from Diazoalkanes. Molecular Structure of μ-Carbonyl-μ-tert-butoxycarbonyl-methylene- bis[carbonyl(η5-cyclopentadienyl)iron] (Fe-Fe)
Authors: Herrmann Wolfgang A. , Plank Johann , Bernal Ivan , Creswick Michael
Published: February 2015

The novel doubly bridged μ-methylene iron complexes μ-[C(H)CO2R]-μ-CO[(η5-C5H5)Fe(CO)]2 (R = C2H5: 3a; R = tC4H9: 3b) have been synthesized by low-temperature photolysis of the corresponding alkyldiazoacetates 2a and 2b, resp., in the presence of [(η5-C5H5)Fe(CO)2]2 (1) and characterized by means of their analytical data and IR, 1H NMR and mass spectroscopy. The geometry of 3b has been established by single crystal X-ray diffraction techniques. δ-Alkyl iron complexes of the type (η5-C5H5)Fe(CO)2[CHRRʹ] are accessible from the corresponding diazoalkanes N2 = CRRʹ.
Synthese und Reaktivität von η5 -Indenyl-trimethylphosphanrhodium(I) - und -rhocüum(III)-Komplexen [1]/Synthesis and Reactivity of η5-Indenyl-trimethylphosphanerhodium (I) and -rhodium(III) Complexes [1]
Authors: Werner Helmut , Feser Rainer
Published: February 2015

The Compounds [(PMe3)2RhCl]2 and [Rh(PMe3)4]Cl react with indenyllithium to give C9H7Rh(PMe3)2. The strong Lewis basicity of this complex is demonstrated by its reactions with NH4PF6, MeI and MeCOCl which lead to the cations [C9H7RhR(PMe3)2]+ (R = H, Me, COMe). The hydrido complex [C9H7RhH(PMe3)2]PF6 reacts with 1,5-C8H12, CO and PMe3 by complete displacement of indene to give [Rh(PMe3)2(C8H12)]PF6, [Rh(PMe3)2(CO)3]PF6 and [Rh(PMe3)4]PF6. Reaction of [C9H7RhH(PMe3)2]PF6 with C2H4 yields an equilibrium mixture containing the cationic tris(ethylene) complex [Rh(PMe3)2(C2H4)3]+ .
Zur Struktur ternärer Übergangsmetallarsenide/On the Structure of Ternary Arsenides
Authors: Pfisterer Martin , Nagorsen Günter
Published: February 2015

New ternary arsenides ET2AS2 (E = Ca, Sr, Ba; T = Cr, Fe, Co, Ni, Cu) were prepared. The cell data were determined by X-ray powder methods. All these compounds crystallize in the tetragonal ThCr2Si2 structure (I 4/mmm), which consists of layers of edge-shared TAS4 tetrahedra. The alkaline-earth atoms are intercalated between the layers.
Über den Einfluß des pH-Wertes auf die polarographische Reduktion der Nitrophenole mit und ohne Zusatz von Campher/On the Influence of the pH Value on the Polarographic Reduction of the Nitrophenols in Presence and Absence of Campher
Authors: Jannakoudakis Dimitrios , Theodoridou Elli
Published: February 2015

The Polarographie behavior of the nitrophenols in the pH range 1-13 and the influence of campher on the polarographic curves are studied. The pH dependence of the half wave potentials and the different reduction of the depolarizers in their molecular or anionic form are discussed.
Solubilization of Methylene Blue in Reversed Micelles, Effect of Water
Authors: Miyoshi Norio , Tomita Giiti
Published: February 2015

The solubilization of methylene blue in dodecylammonium propionate reversed micelles in cyclohexane depended strongly on the solubilized water content. Methylene blue solubilized in the micelle of which head groups are not completely hydrated by bound water exhibited the new absorption bands at 495 and 270 nm, but these bands did not appear in the micelle containing free water. This dye had the absorption bands at 655 and 290 nm in the latter micelle. The solubilizing process and solubilized state of methylene blue in the reversed micelles were discussed with results obtained.
Quantitative Evaluation of the Reactivity of Alkylating Agents
Authors: Bodor Nicholas , Kaminski James J. , Worley S. D. , Gerson Steven H.
Published: February 2015

A sensitive and reproducible method for quantitative evaluation of the relative reactivities of alkylating agents was developed, based on competitve alkylation. The method is superior to the known colorimetric methods. The reactivities of the agents could also be correlated with the 13C chemical shifts of the α-methylene. The method was successfully applied for the ranking of "soft" alkylating agents of low reactivity.
Furanoid Diterpenes in the Bitter Fraction of Teucrium chamaedrys L.
Authors: Papanov Georgi Y. , Malakov Peter Y.
Published: February 2015

Keywords

Two known furanoid diterpenes Teucrin A (1) and Teucrin E (2) were isolated from the bitter fraction of the aerial parts of Teucrium chamaedrys L. Besides these two compounds, Teuchamaedryn A (3) and B (4) were isolated from the better fraction as well. The structure and the stereochemistry of Teuchamaedryn A, B and Teucrin E were established on the basis of spectral evidence, chemical transformation and correlation.
Notizen: Die Kristallstruktur von BaTiS3/Crystal Structure of BaTiS3
Authors: Huster Jürgen
Published: February 2015

BaTiS3, black single crystals, (a = 675.6(1), c = 579.8(1) pm, Z = 2, space group P63/mmc, 4-circle-diffractometer 1° ≤ θ ≤ 24°, AgKa, R=3.1%) is isotypic with BaNiO3, BaVS3, BaTaS3.
Darstellung und Charakterisierung der Tetrabutylammoniumsalze von [Tc2Cl8]2-, [Tc2Cl8]3- und [Tc2Br8]2- Preparation and Characterization of the Tetrabutylammonium Salts of [Tc2Cl8]2-, [Tc2Cl8]3- und [Tc2Br8]2-
Authors: Preetz W. , Peters G.
Published: February 2015

The reduction of [TcCl6]2- with Zn in conc. HCl after evaporation and extraction of ZnCl2 by diethylether yields a red-brown product from which after dissolving in dilute HCl by a solution of (TBA)Cl in CH2Cl2 (TBA)2[Tc2Cl8] and (TBA)3[Tc2Cl8] can be extracted. The separation is achieved by the much better solubility of the green (TBA)2[Tc2Cl8] in acetone compared with that of the grey-blue (TBA)3[Tc2Cl8]. On treatment of (TBA)2[Tc2Cl8] dissolved in acetone with bromine-free conc. HBr carmine red (TBA)2[Tc2Br8] is obtained for the first time. The vibrational spectra are similar and can be assigned according to the assumed D4h-symmetry. In the Raman spectra of both octachloroditechnetates the intensive Tc-Tc-vibration (A1g) is observed at 307 cm-1, for (TBA)2[Tc2Br8] it is found at 323 cm-1 . The electronic spectrum of (TBA)2[Tc2Cl8] agrees to a high extent with that of the corresponding Re compound
(η-Cyclooctatetraen)(η-cyclooctatrienyl)rhodium(I) und einige verwandte Rhodiumkomplexe / (η-Cyclooctatetraene)(η-cyclooctatrienyl)rhodium(I) and Some Related Rhodium Complexes
Authors: Stühler Hans-Otto
Published: February 2015

Reactions of [(COD)RhCl]2 (COD = 1,5-cyclooctadiene) with n-butyllithium in THF and isoprene or 4-vinylcyclohexene lead to formation of the known complexes [(COD)Rh-(1,2-dimethylallyl)] (2) and [(COD)Rh(5-ethylcyclohexenyl)] (3), respectively. With cyclo-octatetraene three complexes are formed:

[(COD)Rh(cyclooctatrienyl)] (4), [(COD)2Rh2-μ-(cyclooctatetraene)] (6), and the title compound (cyclooctatetraene)(cyclooctatrienyl)rhodium(I) (5). It follows from 1H NMR investigations that 5 contains a 1,2,5,6-tetrahapto cyclooctatetraene whilst the cycloocta-trienyl ligand is bound in the symmetrical 3-5-trihapto form, the Rh-atom thus achieving a 16-electron configuration. In solution at -30 °C 5 is converted to a dinuclear complex 7 which apparently can be formulated as (1,2,5,6-η-cyclooctatetraene)-μ-(3-5-η: 1-2:6-7-η]-cyclooctatrienyl) (3-5-η-cyclooctatrienyl)dirhodium(Rh-Rh)
Oberflächenverbindungen von Übergangsmetallen, XXIII [1]. Die Umsetzung cyclischer Olefine mit Oberflächen-Chrom(II) auf Silicagel bei höherer Temperatur / Surface Compounds of Transition Metals, XXIII [1]. The Reaction of Cycloolefines with Surface Chromium (II) on Silicagel at Higher Temperature
Authors: Krauss Hans-Ludwig , Hums Erich
Published: February 2015

By reaction with surface chromium(II) on silicagel at T > 150 °C, cycloolefins can undergo ring contraction, methylation/demethylation, hydrogenation/dehydrogenation, and isomerization. Furthermore, n-alkanes (C1...C4) are formed incorporating support hydrogen. - As in the case of the corresponding acyclic olefins, a common intermediate MC3 (metalla-cyclobutane ⇌ HM-allyl complex) for all these reactions is postulated; the transfer of C1 units is claimed to proceed via a carbene M = CH2 derived from the MC3 precursor
Synthese von Isocumarinen aus Phenylmalonylheterocyclen /Synthesis of Isocoumarines from Phenylmalonyl Heterocyclic Compounds
Authors: Stadlbauer Wolfgang , Ghobrial Nadia , Kappe Thomas
Published: February 2015

Reaction of diphenylcarbonate (2) with enolized phenylmalonyl heterocyclic compounds as the quinolones 1 a-c, the quinolizinones 4 or the phenalenones 6 a, b yields the condensed isocoumarines 3 a-c, 5 or 7 a, b, respectively. Contrary to these results 3-hydroxy-2-phenyl-chinchonic acid (8) or its decarboxylated product 10 do not form the expected isocoumarin 9 but afford the diquinolino-γ-pyrone 11
Untersuchungen an quartären Pyridinium-Salzen, XI [1]. Reaktionen von Cyanpyridinium-Salzen mit Hydroxylamin / Investigations of Quaternary Pyridinium Salts, XI [1]. Reactions of Cyanopyridinium Salts with Hydroxylamine
Authors: Gündel Wolf-H.
Published: February 2015

The preparation of quaternary pyridinium salts with amidoxime group in 2-, 3-and 4-position is described. The isomer with the substituent in 3-position rearranges on addition of base to a 1-hydroxy-2-imino-3-pyridinecarbaldimine. The reaction of 3-cyano-pyridinium salts with hydroxylamine and potassium tert-butoxide gives derivatives of dipyrido[1,2-a: 3′,4′-c]pyrrole
Nitrodiphenylether, ihre Herstellung und herbizide Wirkung / Nitrodiphenylethers, their Preparation and Herbicidal Activity
Authors: Schönowsky Hubert , Bieringer Hermann
Published: February 2015

Nitrodiphenylethers are new herbicides with high activity. Methods for the synthesis of these compounds are reviewed
Dialkylresorcine aus Pseudomonas aureofaciens [1] / Dialkyl Resorcinols from Pseudomonas aureofaciens [1]
Authors: Budzikiewicz H. , Scholl H. , Neuenhaus W. , Pulverer G. , Korth H.
Published: February 2015

2-n-Hexyl-5-n-pentyl and 2-n-hexyl-5-n-heptyl resorcinol have been isolated from Pseudomonas aureofaciens
Ternary Molybdenum Sulfides of the Heavy Alkali Metals
Authors: Kümpers Monika , Schöllhorn Robert
Published: February 2015

Two series of ternary molybdenum sulfides, AxMO4S6 (A = K, Rb, Cs) and A2MO15S20 (A = K, Rb), were prepared by reduction of molybdenum disulfide with alkali metals in alkali halide melts at 1100-1300 K. All compounds are hexagonal and show electronic conductivity; structural characteristics suggest isolated [Mo/S]x-
∞chains as lattice elements for AxMo4S6
Darstellung und Struktur von Phosphazenylcyclophosphazenen / Synthesis and Structure of Phosphazenylcyclophosphazenes
Authors: Dahmann Dirk , Rose Hans , Walz Wolfgang
Published: February 2015

Various phosphazenylcyclophosphazenes N3P3Xn(N = PA3)6-n with X = Cl, F, A = Me, Ph, NMe2, OEt, OPri, OButn and n = 1-3 were obtained by desilylation methods. Chemical and spectroscopical properties dependent on the substituents are discussed. Isomers of di-and tri-substituted compounds were isolated and their structures elucidated by NMR spectroscopy.
Reactions of Ferrocenyldiphenylphosphine. Effects of the Ferrocenyl Group at Phosphorus on the Course of Decomposition of Phosphonium Betaines and Vinylphosphonium Salts
Authors: Allen David W.
Published: February 2015

The reaction of ferrocenyldiphenylphosphine with styrene oxide in ethanol gives, as the major product, ferrocenyl(phenyl)(1,2-diphenylethyl)phosphine oxide (5, R = Ph), the result of a rearrangement involving phenyl migration from phosphorus to adjacent carbon in the decomposition of a vinylphosphonium ion arising from protonation and subsequent elimination of water from the initially-formed phosphonium betaine. A related phenyl migration occurs in the reaction of the phosphine with ethyl propiolate in wet THF. The presence of a ferrocenyl group at phosphorus in Wittig reactions of semistabilised ylides causes the expected decrease in the cis-trans ratio of the resulting alkenes, consistent with its behaviour as an electron-donating substituent.
Starke metallorganische Lewis-Säuren, III [1] Reaktionen von Tricarbonyl-η5-cyclopentadienylmolybdäntetrafluoroborat mit cyclischen Ethern (CH2)nO (n = 2,3,4) und Dioxan / Strong Organometallic Lewis Acids, III [1] Reactions of Tricarbonyl-η5-cyclopentadienyl Molybdenum Tetrafluoroborate with Cyclic Ethers (CH2)nO (n = 2, 3, 4) and Dioxane
Authors: Schloter Klaus , Beck Wolfgang
Published: February 2015

Tetrafluoroborate in (η5-C5H5)(OC)3MoFBF3 is easily substituted by cyclic ethers (CH2)nO (n = 2,3,4)at -30°C in CH2Cl2 to give cationic complexes[(η5-C5H5)(OC)3MoO(CH2)n]+BF4-. With dioxane mononuclear and dinuclear dioxane bridged cationic complexes have been obtained. Ring opening of oxirane in [(η5-C5H5)(OC)3MoO(CH2)2]+ occurs at low tem-peratures; in the presence of oxirane or acetone formation of dioxane or 2,2-dimethyl-1,3-dioxolane, respectively, has been observed. The dioxolane has been obtained also in high yield by direct cyclisation of oxirane and acetone using [(η5-C5H5)(OC)3Mo(acetone)]+ as catalyst.
Ein spiro-bicyclisehes Phosphor-ylid und sein korrespondierendes Phosphoniumkation / A Spiro-bicyclic Phosphorus Yhde and its Corresponding Phosphonium Cation
Authors: Schmidbaur H. , Mörtl A.
Published: February 2015

The spiro-bicyclic ylide

(4) has been synthesized from 1-methyl - phosphorinane (5) via a phosphonium salt precursor [(CH2)5P⊕(CH3)-(CH2)4Br⊖Bre (6) which is cyclized with KH. Two other isomeric ylides (4 a , b) are detected in the reaction mixture by NMR spectroscopy. 4 is characterized by IR, MS, 1H, 13C and 31P NMR spectroscopy, and through conversion into the corresponding phosphonium cation [(CH2)5P(CH2)5]+ (7). A lithiated derivative (8) is obtained in the metalation reaction with LiCH3.
Geometrische Isomerie bei bindungsisomeren Hexakis(thiocyanatoisothiocyanato)osmaten(III) / Geometrie Isomerism of Bond Isomerie Hexakis(thiocyanatoisothiocyanato)osmates (III)
Authors: Peters G. , Preetz W.
Published: February 2015

From the system of isomeric complex ions [Os(NCS)n(SCN)6-n]3-, 9 of 10 possible species, n = 1-6, are isolated, including for n = 2, 3, 4 the first representatives of pure geometric bond isomers. By reaction of K2[OsCl6] with aqueous KSCN solution at reflux temperature, trans(mer)-complexes, and on treatment at 60 °C exclusively cis(fac)- complexes are formed. By ion exchange chromatography on diethylaminoethyl-cellulose columns, from mixtures of pairs of geometric isomers the pure trans(mer)-compounds are enriched in front, the cis(fac)-species at the end of the zones. Characterization and assignment of the configuration of the geometric isomers is based upon the reproducible differences in the IR and Raman spectra.
Reaktion von Triphenylbismutan mit aliphatischen / Dicarbonsäuren Reactions of Triphenylbismuthan with Aliphatic Dicarbonic Acids
Authors: Georgiades Adonis , Latscha H. P.
Published: February 2015

By the reaction of Bi(C6H5)3 with oxalic, malonic, succinic and maleic acids, five-, six-and seven-membered heterocycles with Bi-and O-atoms are formed. During the reaction two phenyl groups are cleaved off.
Nonenzymatie Formation of Energy Rich Phosphates in the Course of Imidazole Oxidation with Fenton's Reagent
Authors: Saygin Ömer
Published: February 2015

Oxidation of substituted imidazoles with modified Fenton's reagent (Fe(II), ascorbic acid, EDTA and H2O2) in aqueous solution at pH 5-7 in the presence of inorganic ortho-phosphate gives high yields of an unknown bound phosphate, in the case of 2-methyl-imidazole up to 35% based on inorganic phosphate. The dependence of the yields on reaction parameters and the hydrolytic behaviour of the compound was studied. The products are unstable in alkaline medium and fairly stable in acid solution (half-life period ca. 1 h at 25 °C in 1 N perchloric acid). Similar bound phosphate was also observed using autoxidation with O2 instead of H2O2.
MNDO-Rechnungen zur unimolekularen CO-Abspaltung aus Isomeren C3H5CO+ -Ionen / MNDO Calculations on the Unimolecular CO Loss from Isomerie C3H5CO+-Ions
Authors: Frenking Gernot , Schmidt Jochen , Schwarz Helmut
Published: February 2015

In agreement with experimental results MNDO calculations indicate that unimolecular CO loss from the isomeric ions CH2 = CHCH2-CO+ (1), c-C3H5-CO+ (2), and CH3CH = CH-CO+ (3), gives exclusively allyl cation (4). It is shown that, whereas CO loss from 1 is a continuously endothermic process, the analogous reaction from 2 and 3 follows relatively complicated pathways. For 2, the energetically most feasible reaction involves an isomerization of 2 to 1 via the intermediate α-oxo-and β-oxocyclobutyl cations (8) and (9). This reaction sequence is 10 kcal • mol-1 lower in energy than direct CO loss from 2 coupled with isomerization of the incipient cyclopropyl cation (7) to allyl cation (4). For 3 it is shown that this ion undergoes isomerization to 2 prior to CO loss. The alternative reaction, i.e. direct CO elimination giving rise to 1-propenyl cation (11) or isomerization to 1 were 35 and 43 kcal • mol-1 higher in energy than the process 3 → 2.