bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proximity Effect in Arene Pi-Complex Formation
Authors: Tsutsui Minoru , Levy Morris N. 
Published: February 2015

A proximity effect in arene π-complex formation from the reaction system of an aryl Grignard reagent and anhydrous chromic chloride was investigated. The yields of arene π-complexes and any accompanying reaction products were compared by the systematic variation of the aryl Grignard reagent employed. Phenyl Grignard gave the best yield of π-complex followed by the benzyl, mesityl and β-ethyl phenyl analogues. The styryl and phenylacetylenyl analogues did not form any π-complexes.
The coupling reaction of benzyl groups gave a new π-complex, π-bibenzyl-π-toluene chromium, along with toluene, bibenzyl and trans-stilbene.
Trans-stilbene was found without forming a trace amount of cis-stilbene. A mechanism for this stereospecific and α-hydrogen elimination coupling reaction is proposed.
Über ein eigentümliches Extraktionsverhalten von Sephadexkörnern der Sorten G 10 und LH 20 gegen wäßrige Suspensionen einiger carcinogener und nichtcarcinogener Kohlenwasserstoffe
Authors: Wilk Manfred , Rochlitz Jürgen 
Published: February 2015

Wäßrige Sephadex-Gele nehmen Vielfache der in Wasser gelösten Anteile polycyclischer, aromatischer Kohlenwasserstoffe auf, wenn diese als Suspension vorliegen. Beobachtbar ist dieser Effekt an der Erhöhung der Fluoreszenzintensität des gelösten Anteils der Aromaten bei Zugabe von Sephadex-Körnern und anschließender kräftiger Rührung. Verwertbar ist dieses Phänomen zumindest für die Ermittlung der Lage der Emissionsbanden der Kohlenwasserstoffe in Wasser, denn es bestehen nur geringe Unterschiede zwischen den Fluoreszenzsprektren in Sephadex und Wasser. Weiterhin ist beachtlich, daß die carcinogenen Kohlenwasserstoffe nach diesen ersten orientierenden Versuchen, zu einer Gruppe gehören, die eine geringe Diffusionsgeschwindigkeit in das Sephadex-Gel, bei gleichzeitigem Erreichen relativ hoher Endkonzentrationen, besitzen. Der Quotient aus beiden Größen wird daher für die Carcinogene maximal. Nach Desoxycholsäure, Detergentien 4, 11, 14; 15, Purinen 3, 5, 12, 18, 10, 22, Desoxynucleinsäuren 2, 6, 7, 9, 17, Adenosintriphosphat 24 und Proteinen 12, 11, 14; 15 wurde damit gefunden, daß auch Polysaccharid-artige Systeme in der Lage sind, Lösungs-vermittelnd auf Kohlenwasserstoffe in wäßriger Phase zu wirken (vgl. auch 8).
Es verspricht daher, interessant zu werden, an Sephadex, als primitivem Modell von Zellbestandteilen, in der Zukunft standartisierte Kohlenwasserstoff-Suspensionen in dieser Weise zu untersuchen und gleiche Experimente mit stärker hydrophobiertem Gel durchzuführen.
Cyclische Diazastannylene, III1 Die Kristall-und Molekülstruktur der monoklinen Phase von 1.3-Di-tert-butyl-2.2-dimethyl-1.3.2.4λ2 -diazasilastannetidin / The Crystal and Molecular Structure of the Monoclinic Phase of 1,3-Di-feri-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine
Authors: Veith M. 
Published: February 2015

Abstract
The crystal and molecular structure of the monoclinic phase of 1,3-di-tert-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine has been determined from three-dimensional X-ray data collected on a two-circle diffractometer at -120 °C (MoKa radiation, 2623 reflexions, R - 0,050). The crystals are monoclinic, space group C2/c, with cell dimensions a = 10.655(5), b = 25.75(1), c = 17.33(1) Å, β = 106.8(1)° and Z = 12. Four monomeric (crystal site symmetry 2 (C2)) and four dimeric units (crystal site symmetry 1̄ (Ci)) are present in the structure interacting over tin-tin (3.68 Å). Remarkable are the very short Sn-N bond (2.09 Å) in the monomer and the donation bond Sn-N (2.39 Å) in the dimer. The coordination of the tin atoms in the different units is discussed in detail.
Koordinationschemie ambivalenter Liganden, VIII1 Synthese und Reaktivität ionischer und kovalenter Sulfinato-Komplexe von Tetraorganyl-VB-Elementen des Typs R4'EO2SR / Coordination Chemistry of Ambivalent Ligands, VIII1 Synthesis and Reactivity of Ionic and Covalent Sulfinato Complexes of Tetraorganyl-VB-Elements of the Type R4'EO2SR
Authors: Lorenz Ingo-Peter , Thekumparampil John Koshy 
Published: February 2015

Abstract
The synthesis of the sulfinato derivatives 1-7 of pentavalent VB-elements follows equation (2). These compounds differ significantly in their physical and chemical properties and in their structures. In between the extremes of the purely ionic tetramethylam-monium sulfinates la-c and the typically covalent and pentacoordinated tetraorganyl-sulfinato-O-stiboranes 6-7, there are the hexa-or pentavalent compounds of phosphorus and arsenic 2 and 4 or 3 and 5 with sulfinato-O,O' or sulftnato-O linkage, which dissociate readily into their ionic components. 1 a-c are suitable for the synthesis of sulfones according to equation (3). All of the methylsulfinato derivatives can be easily transformed (equation (4)) into the corresponding sulfonates by air oxidation. Only the tetraphenylsulfinato-O-stiboranes 7 a-c show SO2-elimination forming pentaorganylstiboranes (equation (5)). IR, mass and in some cases NMR spectra are reported.
Derivatives of 5H-Cyclopenta[2,1-b : 3,4-b']dipyridin-5-one (4,5-Diazafhioren-9-one)
Authors: Eckhard Ian F. , Keats Neil G. , Summers Lindsay A. 
Published: February 2015

Abstract
Derivatives of 5H-cyclopenta[2,1-b:3,4-b']-dipyridin-5-one including representatives of the new heterocyclic diquaternary system 4H-7a,9a-diazoniacyclopenta[def ]phenanthrene have been synthesised and the herbicidal and redox properties of the salts studied. The mass spectrum of 5-hydroxy-5-methyl-5H-cyclopenta-[2,1-b: 3,4-b'Jdipyridine is also reported.
Untersuchungen an quartären Pyridinium-Salzen, VII1 Pyridinium-Salze mit Harnstoff-und Carbamidester-Gruppe. Darstellung einiger Betaine / Investigations of Quaternary Pyridinium Salts, VII1 Quaternary Pyridinium Salts with Urea or Carbamate Group. Preparation of Inner Salts
Authors: Gündel Wolf-Hellmut 
Published: February 2015

Abstract
Ten new quaternary pyridinium salts with urea or carbamate group were prepared and the acidity constants determined. On addition of base to the salts ot pyridyl-urea, stable inner salts could be isolated.
6 H-Dipyrido [2,1-b: 1',2'-e] -1,3,5-selenadiaarinium Dibromide: A Dipyrido Analogue of Selenaxanthene
Authors: Grant Hamish G. , Summers Lindsay A. 
Published: February 2015

Abstract
2,2'-Selenodipyridine on reaction with dibromomethane affords the new polycyclic system, 6H-dipyrido[2,1-b :1',2'-e]-1,3,5-selenadiazinium dibromide.
Indole [3,2 gjindolizidines via Sodium Borohydride Reduction of Indolic Imides
Authors: Speckamp W. N. , Dijkink J. , Pasman P. , Hubert J. C. 
Published: February 2015

Abstract
Acid-controlled sodium borohydride reduc-tion of imides followed by cyclisation of the carbinol lactams formed affords the title compounds in good yields.
Kristall- und Molekül-Struktur von 4-Phenyl-1.2.3–thiadiazol-3-oxid / Crystal and Molecular Structure of 4-Phenyl-1,2,3-thiadiazol-3-oxide
Authors: Winter Werner , Plücken Udo , Meier Herbert 
Published: February 2015

Abstract
A final decision between the 2-and 3-oxide structure of the thermally or photo-chemically accessible monoxides of 1,2,3-thiadiazoles is given with the aid of an X-ray analysis of 4-phenyl-1,2,3-thiadiazole-3-oxide. The compound crystallizes in the ortho-rhombic space group Pbca, Z = 8, with a = 7.598(6), b= 18.865(5) and c= 11.225(6) Å.
The structure was solved by the heavy atom method and refined to R = 0.042 for 1643 independent reflections. The heterocyclic ring is planar within experimental error and the bond distances S-C and S-N are rather short. In the crystal the molecules are linked by an unusual short contact distance between sulphur and oxygen (2.75 Å).
Radiolysis of Cytosine, 5-Methyl Cytosine and 2'-Deoxycytidine in Deoxygenated Aqueous Solution A Pulse Spectroscopic and Pulse Conductometric Study of the OH Adduct
Authors: Hissung Alfred , Sonntag Clemens von 
Published: February 2015

Abstract
Using the pulse radiolysis technique the OH adducts of cytosine, 5-methyl cytosine and 2'-deoxycytidine were investigated in alkaline N2O saturated aqueous solutions. Ab-sorption spectra were recorded and their change with time was correlated with the change in conductivity. An OH -induced reaction (1.4·108)·mol-1·s-1) was observed with OH adducts of cytosine and 5-methyl cytosine leading to radicals (pK=10.3), the G-values of which were 3.2 and 1.6 respectively (conductivity measurements). These intermediates were assigned to the C-5 OH radical adducts.
After completion of the free radical reactions (2k = 6 · 108)·mol-1·s-1) the resulting product mixture showed pK-values of 8.3 (cytosine, G=0.6), 10.5 (5-methyl cytosine, G=0.8), 10.7 (cytosine, G=1.5; 2′-deoxycytidine, G=1.5) and 12.4 (cytosine, no G-value, determinable with optical detection). Ammonia, which is a product measured after γ-radiolysis of all the three compounds investigated (G(NH3) = 0.6 ± 0.1), is not released within 15 ms after the pulse.
Free Radical Induced Oxidation of Neutral Aqueous Solutions of D-Glucose in the Presence of Oxygen - a Non-Chain Process
Authors: Schuchmann Man Nien , Sonntag Clemens von 
Published: February 2015

Abstract
Oxygenated 1M aqueous solutions of 2-methyltetrahydrofuran (MTHF) or D-glucose were γ-irradiated, and G(total peroxide) was determined as a function of dose rate and temperature. Whereas MTHF was oxidized by a chain process, D-glucose was not. The peroxyl radicals derived from D-glucose rapidly eliminate HO2·. At natural pH HO2·(pK=4.75) is largely deprotonated. O2- does not propagate a chain.
Synthesis of Some 7,8-Disubstituted 2-Trifluoromethyl Phenothiazines and their Sulphoxides
Authors: Mittal M. , Mital R. L. 
Published: February 2015

Abstract
2-Chloro-5-methoxy-p-benzoquinone [1] reacts with zinc mercaptide [2] to give 2-tri-fluoromethyl-8-methoxy phenothiazin-7-one (1), which on reduction with sodium di-thionite provided 2-trifluoromethyl-8-methoxy phenothiazin-7-ol. Synthesis of various acylated and alkylated derivatives (3 to 6) and their sulphoxides (7 to 8) have been described (Scheme 1).
Tri- und Tetraseleninato-Komplexe von Zinn / Tri- and Tetraseleninato Complexes of Tin
Authors: Lindner Ekkehard , Ansorge Ulrich 
Published: February 2015

Abstract
Two tri- and tetraseleninato complexes of tin, RSn(O2SeR)3 (1) and Sn(O2SeR)4 (2) (R =C6H5), are obtained from trichlorophenyltin and tetra-chlorotin ,resp. with sodium benzeneseleninate. On the basis of the IR and Raman spectra 1 and 2 probably are polymeric mixed seleninato-O,O′-seleninato-O complexes (c.n. = 6).
Bentonit – ein Schichtsilikat - als Katalysator bei der elektrophilen aromatischen Substitution / Bentonite, a Layered Silicate in Electrophilic Aromatic Substitution
Authors: Gosselck J. , Lötz W. W. 
Published: February 2015

Abstract
Bentonite is used as an heterogenous catalyst in the liquid-phase alkylation of benzene and toluene.
Optisch aktive Übergangsmetall-Komplexe, LVII [1] (+)- und (-)-C5H5M(CO)(P∅2R*)X mit M = Fe, 57Fe und X = I, COCH3, CH3 / Optically Active Transition Metal Complexes, L VII [1] (+)- and (-)-C5H5M(CO)(P∅2R*)X with M = Fe, 57Fe, and X = I, COCH3, CH3
Authors: Brunner Henri , Muschiol Manfred , Nowak Wilfried 
Published: February 2015

In the reaction of C5H5Fe(CO)2l and C5H5Fe(CO)2CH3, respectively, with S-(+)-(C6H5)2PN(CH3)CH(CH3)(C6H5) (abbreviated P∅2R*) the complexes C5H5Fe(CO)(P∅2R*)I (1), C5H5Fe(CO)(P∅2R*)COCH3 (2), and C5H5Fe(CO)(P∅2R*)CH3 (3) are formed as pairs of diastereoisomers the components of which differ only in the configu­ration at the iron atom. CsH5Fe(CO)(P∅2R*)CH3 (3) can be obtained in higher yield by photochemical decarbonylation of C5H5Fe(CO)(P∅2R*)COCH3 (2). The (+)365- and (-)365-diastereoisomers of each pair exhibit different chemical shifts in the 1H NMR spectra. Diastereoisomer separation can be achieved by fractional crystallization.
Starting with 57Fe metal (-)365-C5H5
57Fe(CO)(P∅2R*)I was prepared via 57Fel2, 57Fe(CO)4l2, C5H557Fe(CO)2l, and C5H557Fe(CO)(P∅2R*)I in order to demonstrate optical activity of a 57Fe compound in the y region by Mössbauer polarimetry in later experiments to be reported elsewhere.
Organische Schwefelverbindungen, XXIX [1] Thiocarbonyl-Derivate von 2-Thioxo-Malonsäureestern / Organic Sulfur Compounds, XXIX [1] Thiocarbonyl Derivatives of 2-Thioxomalonic Acid Esters
Authors: Beelitz Klaus , Höhne Gerhard , Praefcke Klaus 
Published: February 2015

Abstract
The first derivatives of the hitherto unknown 2-thioxo malonic acid ester could be achieved. In dependence of conditions and presence of an enophile (3) substituted dihydro thiopyrans (5) as 4 + 2 addition products of hypothetic 2-thioxo malonic acid esters with 3 or α-oxo-methylene bisxanthates 7 resp. are formed in reactions of dibromo malonic acid esters 1 with potassium O-ethylxanthate (2).
Zur ionischen Leitfähigkeit gemischter Lithiumiodid-Verbindungen / The Ionic Conductivity of Mixed Lithium Iodide Samples
Authors: Eichinger Günter 
Published: February 2015

Abstract
The ionic conductivity of some polycrystalline samples of the general formula Lil · yXI(y = 1/4 or 1/10) X = Rb+, NH4+, N(CH3)4
+, NEt4
+) is measured. These mixtures generally exhibit higher activation energies for ionic movement than pure lithium iodide. At temperatures above 50 °C, the overall conductivity is higher them that of pure lithium iodide.
Über Tetraphenylphosphonium-Isopolymolybdate / Tetraphenylphosphonium-Isopolymolybdates
Authors: Grase Roger , Fuchs Joachim 
Published: February 2015

Abstract
From acidified sodium molybdate solutions mixtures of two polymolybdates are precipitated by addition of tetraphenylphosphonium ions. The pure compounds obtainable by separation with selective organic solvents were identified analytically and by their vibrational spectra as octamolybdate, [P(C6H5)4]4Mo8O26, with "Lindqvist structure" and as hexamolybdate, [P(C6H5)4MO6019. They are characterized by their UV-VIS spectra and X-ray powder patterns. The precipitation of the hexamolybdate from strong acidic solution can be used analytically for the determination of molybdenum.
Die Kristallstruktur von Tetramethylstiboniumtetrachlorogallat [(CH3)4Sb]+[GaCl4]- / The Crystal Structure of Tetramethylstibonium Tetrachlorogallate [(CH3)4Sb]+[GaCl4]-
Authors: Hausen Hans-Dieter , Binder Herbert , Schwarz Wolfgang 
Published: February 2015

Abstract
Tetramethylstiboniumtetrachlorogallate crystallizes in the hexagonal space group P63mc with two formula units per cell. The lattice constants are a=b = 768.8 pm and c= 1251.2 pm. The structure shows isolated cationic and anionic tetrahedra, which are only slightly distorted. The averaged bond lengths are: Sb-C 212.6 pm and Ga-Cl 217.2 pm.
In good agreement with the short Ga-Cl distance (the shortest of all compounds ((CH3)nGaCl4-n)-; n = 1-3) are the measured ionization energies of Ga-3d-electrons and the calculated Pauling Qp-values.
Über Derivate des Hydrazins, VIII [1] Bis(trimethylsilyl)amino-isocyanat und -isothiocyanat / On Derivatives of Hydrazine, VIII [1] Bis(trimethylsilyl)amino-isocyanate and -isothiocyanate
Authors: Wiberg Nils , Hübler Gerhard 
Published: February 2015

Abstract
Bis(trimethylsilyl)aminoisocyanate (1) is formed by reaction of the hydrazides LiN2(SiMe3)3 or Li2N2(SiMe3)2 with phosgene. Bis(trimethylsilyl)aminoisothiocyanate (2) is obtained by thermolysis of the hydrazide (Me3Si)3N2CSSLi, which is readily prepared from LiN2(SiMe3)3 and carbon disulfide. (It is generally found that LiN2(SiMe3)3 and Li2N2(SiMe3)2 add to heterocumulenes X = C = Y (X = TosN, O, S; Y = O, S), and that reaction of the addition products with Me3SiCl yields (Me3Si)3N2CXYSiMe3. While 1 is obtained solely as a thermostable dimer, 2 is a thermolabile monomer). Thermolysis of 2 at ambient temperature yields (Me3Si)4NiC2S and (Me3Si)4NiC2S3. Thermolysis of 2 in ether solution at elevated temperatures mainly yields bis(trimethylsilyl)carbodiimide and sulfur
Darstellung und Kristallstruktur von K3Cu3P2 / On the Preparation and Crystal Structure of K3CU3P
Authors: Savelsberg Gerhard , Schäfer Herbert 
Published: February 2015

Abstract
K3CU3P2 was obtained by melting potassium, copper and red phosphorus in an sealed copper vessel. The compound crystallizes trigonally with a = 572 ± 2 pm, c = 1993 ± 3 pm, R3m, Z = 3. The structure analysis revealed nets of puckered 12-membered rings in which the Cu-atoms are linearly coordinated while the P-atoms are located on the apices of trigonal pyramids
Li5NaSn4 - eine Phase mit gewellten Sn-Sechsecknetzen / Li5NaSn4 - a Phase with Puckered Nets of Six-Membered Sn-Rings
Authors: Volk Klaus , Müller Wiking 
Published: February 2015

Abstract
The new compound LisNaSiu has been prepared and its crystal structure determined. It crystallizes trigonal, a = 471.0 ± 0.6 pm, c = 3172 ± 5 pm, space group R3m-C5
3V. Half of the Sn atoms build up a puckered net of connected six-membered rings, the other half is bound to the net atoms, forming a tetrahedral Sn-Sn coordination for these. The structural relations of this Sn sublattice to the diamond lattice are discussed
Mechanism of Hg(II) Oxidation of D-Galactose in Alkaline Medium
Authors: Singh M. P. , Singh A. K. , Kumar Mandhir 
Published: February 2015

Abstract
The present paper deals with the kinetics of oxidation of D-galactose by Nessler's reagent in alkaline medium. The reaction is zero order with respect to Hg(II) and first order with respect to reducing sugar. The direct proportionality of the reaction rate at low hydroxide ion concentrations shows retarding trend at higher concentrations. The reaction rate is inversely proportional to iodide ion concentration. A mechanism has been proposed taking HgI3- as the reacting species
Kurzzeitpyrolyse, VIII [1] Reaktionen bei der CO-Eliminierung aus ehinoiden Verbindungen / Short Time Pyrolysis, VIII [1] Reactions after CO-Elimination from Quinoid Compounds
Authors: Schaden Gerhard 
Published: February 2015

Abstract
Fuchsone (4-diphenylmethylene-2,5-cyclohexadien-l-one) (1) eliminates CO upon gasphase pyrolysis. The resulting biradical (2) either formes by double ring closure and dehydrogenation benzo[c]phenanthrene (6) or recombines to 6,6-diphenylfulvene (3) which gives after dehydrogenative ring closure and rearrangement 1-phenylacenaphthylene (11)
Reaction of Br3
·2- with 2-Deoxy-D-ribose. A Preferred Attack at C-1
Authors: Parsons Barry J. , Schulte-Frohlinde Dietrich , Sonntag Clemens von 
Published: February 2015

Abstract
In the photolysis of 5-bromouracil containing DNA Br atoms are expected inter mediates. In order to evaluate the possible site of attack of the Br atom at the sugar moiety of DNA the reaction of 2-deoxy-D-ribose with the Br atom (complexed with two bromide ions) was investigated. Hydroxyl radicals generated by the radiolysis of N2O saturated aqueous solutions were converted into Br3
·2- radicals by 1 M bromide ions. Br3
·2- reacts with 2-deoxy-D-ribose (k = 3.7 · 104M-1s-1, pulse radiolysis). The major product is 2-deoxy-D-erythro-pentonic acid (G = 2.4, γ-radiolysis). It is formed by hydrogen abstraction from C-l and oxidation of this radical by other radicals. An alternative route via the radical at C-2 is neglible. It follows that Br3
·2- reacts preferentially at C-1 of 2-deoxy-D-ribose
Zur Besetzung von Oktaederund Tetraederpositionen in Bi2Ca2Fe2O9 / About Occupation of Octahedral- and Tetrahedral Positions of Bi2Ga2Fe2O9
Authors: Müller-Buschbaum Hk. , Chales de Beaulieu D. 
Published: February 2015

Abstract
Single crystals of Bi2Ga4O9 and Bi2Ga2Fe2O9 were prepared by CO2-Laser technique and analysed by X-ray single crystal methods. Bi2Ga4O9 is one of the rare examples containing Ga3+ in octahedral as well as tetrahedral surrounding of oxygen. In Bi2Ga2Fe2O9 the coordination of oxygen atoms around Ga3+ is exclusively tetrahedral. Thus this compound represents positive evidence of the preferential occupation of tetrahedral holes by gallium
Die Kristallstruktur von Na3AsS4 • 8 H2O / The Crystal Structure of Na3AsS4 • 8 H2O
Authors: Dittmar Günter , Schäfer Herbert 
Published: February 2015

Abstract
Na3AsS4 • 8 H2O crystallizes in the space group P21/c with the cell parameters a = 865,1(3), b = 1299,5(4), c = 1359,6(5) pm, β = 102,77(7)°. The cell contains 4 formula units. The structure found consists of tetrahedral AsS4-groups and Na-Ions, octahedrally coordinated by water molecules and/or sulfur atoms
The X-ray Structure of N4P4Cl7(NPPh3) - a Novel Conformation of the NPPh3 Group
Authors: Sudhakara Babu Y. , Manohar H. , Stanley Cameron T. , Shaw Robert A. 
Published: February 2015

Abstract
The X-ray crystal structure of heptachloro- (triphenylphosphazenyl)cyclotetraphosphazatetraene N4P4Cl7(NPPh3) reveals a novel conformation (tending to Type III) of the triphenylphosphazenyl group with respect to the adjacent ring segment. This observation is contrasted with the structure of N3P3Cl5(NPPh3) where a Type I conformation is observed
A NMR Study of the Exchange Kinetics of the Nonamethylimidodiphosphoramide with its Complexes of Diamagnetic Cations
Authors: Rubini P. R. , Rodehüser L. , Delpuech J.-J. 
Published: February 2015

Abstract
The ligand exchange on nonamethylimidodiphosphoramide (NIPA) complexes is found to be very slow comparatively to analogous monodentate ligands; the rates determined by 1H or 31P NMR spectroscopy are: k(25°C)=4.3 × 10-2 s-1; 31.6 s-1 • M-1; 3.7 × 104 S-1 • M-1 and 1.35 × 104 s-1 · M-1 for Mg2+, Ca2+, Sr2+ and Li+ cations respectively. For the Al3+, Ga3+, In3+ and Be2+ ions no exchange could be detected by 1H NMR spectroscopy up to 120 °C, indicating rates lower than about 10-3 s-1
Langlebige Radikalkationen und anodische Substitution einfacher Aromaten / Long-lived Radical Cations and Anodic Substitution of Simple Arenes
Authors: Fritz Heinz P. , Gebauer Helmut 
Published: February 2015

Abstract
In media of low nucleophilicity solutions of coloured radical cations of simple arenes can be obtained by anodic oxidation. A straightforward mechanism for the nucleophilic substitution of these species is suggested by the experimental results.
Cation-Ordering in Synthetic Mg2-xFexSiO4-Olivines
Authors: Riekel Ch. , Weiss Armin 
Published: February 2015

Abstract
In annealed, synthetic samples of Mg2-xFexSiO4 the Mg2+ and Fe2+ ions are not randomly distributed. With 0.1 ≦ x ≦ 0.6 the larger Fe2+ ions replace preferentially Mg2+ in octahedral sites of symmetry m and the lattice dimensions do not change in this range. Quenching tends to yield samples with more randomly distributed cations and the lattice dimensions approach those of natural olivines.
The Stereochemistry of P-N Bond Cleavage in the Staudinger -Wittig-type Reaction of 2-Anilido-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine-2-thiones
Authors: Lesiak Krystyna , Stec Wojciech J. 
Published: February 2015

Abstract
Both isomers of 2-anilido-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine-2-thiones (2 a and 2 b) derived from (-)ephedrine were obtained and converted to corresponding 2-thiomethyl derivatives (3 a and 3 b). The Staudinger-Wittig-type reaction of P-N bond cleavage was found to proceed with full retention of configuration at P-atom involved into five-membered ring system.
Untersuchung yon Dipeptiden durch Elektronenstoß-und Felddesorptions-Massenspektrometrie / Investigation of Dipeptides by Electron Impact and Field Desorption Mass Spectrometry
Authors: Lüderwald I. , Przybylski M. , Ringsdorf H. , Silberhorn D. 
Published: February 2015

Abstract
The combined application of field desorption and electron impact ionization techniques in the mass spectrometry of free dipeptides can be used to obtaine informations about primary structure and molecular weight. Characteristic fragmentation pathways of dipeptides are discribed and the mechanism of diketopiperazine formation is discussed.
Deblocking of 2-Bromoethyl Esters via Thiazolium Salts
Authors: Ho Tse-Lok 
Published: February 2015

Abstract
Carboxylic acids are recovered from 2-bromo-ethyl esters by successive treatment with 4-methyl-5-thiazoleethanol, sodium bicarbonate followed by pyrolysis and quenching with dilute acid.