bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kupfer(I)-chlorid-Addukte von Phosphoraniminen Die Kristallstrukturen von Ph 3 PNPh * CuCl und von 2,3-Bis(triphenylphosphoranylidenamino)maIeinsäure-N-methylimid- Kupfer(I)-chlorid / Copper(I) Chloride Adducts of Phosphoranimines The Crystal Structures of Ph3 PNPh·CuCl and of 2,3-Bis(triphenylphosphoranylideneamino)maleic Acid N-Methylimide Copper(I) Chloride
Authors: Maurer Andrea , Fenske Dieter , Beck Johannes , Strähle Joachim , Böhm Eberhard , Dehnicke Kurt 
Published: March 2015

Abstract
The title compounds Ph3PNPh · CuCl (1) and (Ph3P)2 N2 C4O2 (NMe) CuCl (2) have been prepared by the reactions of CuCl with the corresponding phosphoranimines Ph3PNPh and 2.3-bis(triphenylphosphoranylideneamino)maleic acid N-methylimide, respectively. Both com-plexes were characterized by their IR spectra as well as by crystal structure determinations.
Ph3PNPh · CuCl (1): space group P1, Z = 4, 3639 independent observed reflexions, R = 0.038. Lattice dimensions (18 °C): a = 1047.6; b = 1251.5; c = 1755 pm; α = 103.43°; β = 97.24°; γ = 101.30°. The compound forms monomeric molecules; the asymmetric unit contains two crystallo-graphically independent molecules. The CuCl molecule is bonded via the N atom of the phos-phoranimine. Bond lengths: Cu-N = 189 pm; Cu-CI = 209 pm; bond angle N - Cu - CI = 177°.
(Ph3P)2N2C4O2(NMe) · CuCl (2): space group Pbca, Z = 8, 5611 independent, observed reflexions, R = 0.069. Lattice dimensions (25 °C): a = 1224.3; b = 1962.5: c = 2994.0 pm. The compound forms monomeric molecules with the CuCl molecule bonded via one of the N atoms of the phosphoranimine groups. Bond lengths: Cu - N = 194 pm; Cu-CI = 212 pm; bond angle N-Cu -CI -175°.
Elektronenreiche Olefine, 1 / Electron Rich Olefins, 1
Authors: Hausen Hans-Dieter , Kaim Wolfgang 
Published: March 2015

Abstract
Crystal and molecular structure analysis of the electron rich title compound exhibits an undistorted, yet sterically shielded tetra(primary alkyl)-substituted double bond system with alternating anti-periplanar CH2SiMe3 substituents. The diastereotopic methylene protons have been located and their position correlated to the 1HNMR data and to the ESR hyperfine coupling constants of the corresponding radical cation. In contrast to the highly inert all-carbon derivative, tetraneopentylethene, the more electron-rich and more flexible organosilicon title compound reacts with bromine. Close to orthogonal arrangement between the C-C(H2)-Si planes and the ethene plane ensures effective, fourfold σ/π-hyperconjugation.
DarsteIlung und Schwingungsspektren des 13C- und 18O-Hiarkierten trans-Dioxotetracyanoosmats(VI), [OsO2(CN)4]2- / Preparation and Vibrational Spectra of 13C and 18O Labelled trans-Dioxotetracyanoosmate(VI), [OsO2(CN)4]2-
Authors: Preetz W. , Sartori C. 
Published: March 2015

Abstract
Through careful acidification of the aqueous solution of [OsO2(OH)4]2- in the presence of CN- or 13CN- with acetic acid, [OsO2(CN)4]2- or [OsO2(12CN)4]2- are formed, respectively. The reaction of Os18O4 and tetrabutylammonium cyanide with glacial acetic acid in anhydrous methanol yields [Os18O2(CN)4]2- . The shifts of the infrared and Raman bands of the isotopically labelled complexes are in good agreement with Teller-Redlich calculations. The degenerate E modes, expected for tetragonal symmetry, are split by approx. 15 cm-1, indicating an orthorhombic distortion of the complex ion in the solid state. Therefore, all the observed IR- and Raman frequencies are assigned according to point group D2h. For the complex containing an 18O=Os=18O axis, the symmetry is lowered to C2v, and the rule of mutual exclusion is restricted. This results in a weak absorption in the infrared spectrum of the Raman active symmetric OsO stretching vibration and vice versa a weak band in the Raman spectrum for the antisymmetric infrared active mode.
Erdalkaliquadratate, VI [1] SrC4 O4 · 3H2O, Typ III / Alkaline-earth Squarates, VI [1] SrC4O4 ·3H2O, Type III
Authors: Robl Christian 
Published: March 2015

Abstract
SrC4O4 ·3 H2O, type III. was obtained in an aqueous silica gel besides crystals of SrC4O4-3 H20. type I. X-ray crystal structure analysis showed close relationship to BaC4O4-3H20. but no isotypism. Sr2+ is coord|inated by four water molecules and four oxygen atoms of the squarate dianion. The connection of Sr2+ with C4O4
2- leads to layers. The geometry of C4O4
2- is typical for delocalized π-systems. The Osquarate atoms are not equally bound to Sr2+. One Osquaralc atom (0(4)) is bound to two Sr2+, two (O(1). O(2)) are bound to one Sr2+, respectively, and the fourth Osquaratc atom (0(3)) shows no bonding contact to Sr2+. These differences are compensated for by intermolecular hydrogen bonds which involve O(3) three times, O( I) and O(2) once each, but not O(4).
Ein Chelatligand mit einer -NSSSN-Kette: Bis(oxamido)trisulfan und sein Kupferkomplex / A Chelate Ligand with a -NSSSN-Chain: Bis(oxamido)trisulfane and its Copper(II) Complex
Authors: Brunn Karl , Endres Helmut , Weiss Johannes 
Published: March 2015

Abstract
Bis(oxamido)trisulfane was obtained first as a by-product in the synthesis of 3,4-dihydroxy- 1,2,5-thiadiazole, later in direct syntheses from 3,4-diethoxy-1,2,5-thiadiazole. Reaction with anhydrous CuCl2 gave bis(oxamido)trisulfane copper(II). Bis(oxamido)trisulfane is monoclinic P21/n, a = 8.975(2) A. b = 8.875(1) Å, c = 12.781(2) Å. β = 94.40(2)°, V = 1015.05(4) Å3, Z = 4, Mr = 270.31, Dx = 1.76 g cm-3, MoKα,λ = 0.7107 Å, μ = 7.0 cm-1 , wR = 0.038 for 1371 observed independent reflections.
Bis(oxamido)trisulfane copper(II) is triclinic PI, a = 5.279(1) Å, b = 11.388(3) Å, c = II.943(4) Å, a = 89.08(2)°, β = 82.62(2)°, γ = 86.44(2)°, V = 710.8(3) Å3, Z = 2, Mr = 331.83, Dv = 1.56 gcm-1, MoKα,λ =0.7107 Å, μ = 19.89 cm-1, wR = 0.039 for 1974 observed independent reflections.
Untersuchungen an Polypseudohalogeniden, V[1] Darstellung und Kristallstruktur des Kaliumdicyanoiodats(I), K[I(CN)2] / Studies on the Polypseudohalides, V [1] Preparation and Crystal Structure of K[I(CN)2]
Authors: Tebbe Karl-Friedrich , Krauß Norbert 
Published: March 2015

The new compound K[I(CN)2] can be prepared by addition of one formula unit of iodine to a concentrated aqueous solution of two mole equivalents of potassium cyanide. It crystallizes in the monoclinic space group C2/m with a = 736.4, b = 451.4, c = 908.0 pm, β = 92.56° and Z = 2. The crystal structure has been refined to Rf = 0.020 for 301 observed reflections.
The structure may be described as a layer-like package of cations K+ and trihalide-analogous anions [I(CN)2]-. The anions are strictly linear at the I atoms (symmetry 2/m) and nearly linear at the C atoms with φ (I-C-N) = 178.6° and d(I-C) = 229.8, d(C-N) = 112.9 pm. The cation is surrounded by a slightly distorted octahedron of nitrogen atoms with d(K···N) = 284.8,292.6 pm
Koordination des dreizähnigen makrocyclischen Liganden 1-Thia-4,7-diazacyc!ononan an Palladium(II) und Platin(II) / Coordination of the Tridentate Macrocyclic Ligand 1-Thia-4,7-diazacyclononane to Palladium(II) and Platinum(II)
Authors: Hoffmann Peter , Mattes Rainer 
Published: March 2015

The reaction of PdAc2 and K2PtCl4 with the ligand 1-thia-4,7-diazacyclononan (C6H14N2S - L) yield crystals of [PdL2](PF6)2 (4) and [PtL2]Br2-H2O (5), respectively. The structures of 4 and 5 have been determined.
Crystal data: 4, monoclinic, space group P21/c, a = 719.2(1), b = 1712.5(3), c = 936.8(2) pm. β = 99.15°, Z = 2; 1708 reflections, R = 0.029.
5, monoclinic, space group P21/c, a = 1682(2). b = 786(1), c = 1573(1) pm. β = 108.1(1)°, Z - 4; 1706 reflections, R = 0.070. 4 contains octahedrally coordinated Pd(II); in addition to the square planar PdN4 group (mean Pd -N bond length 206 pm) the S-donor atoms are weakly coordinated in the axial positions (Pd-S: 303.4(1) pm). In 5, however, Pt(II) is in a square planar ligand environment. The S-donor atoms are bent away from the axial positions of the central atom.
Reaktive E=C(p—p)π-Systeme, XVI [1] Trimethylstannvlphosphane des Typs Me3SnP(R)CF3 (R = Me, Et) als Phosphaalken-Vorstufen / Reactive E=C(p-p)π-Systeme, XVI [1] Trimethylstannylphosphanes of the Type Me3SnP(R)CF3 (R = Me, Et) as Phosphaalkene Precursors
Authors: Grobe Joseph , Szameitat Jürgen 
Published: March 2015

Abstract
Stannylphosphanes of the type Me3SnP(R)CF3 [R = Me (1), Et (2)] have been prepared by a multistep synthesis (Fig. 1) starting either with F3CPI2 or with P(NEt2)3. Due to the alkyl sub­stituents, 1 and 2 show a higher thermal stability than the analogous perfluoroalkyl compounds Me3SnP(RF)2 (RF = CF3, C2F5). Pyrolysis of 1 and 2 at 380 °C/10-3 Torr gives the new phosphaalkenes RP=CF2 (R = Me, Et) as reactive intermediates collected at -196 °C. They polymerize on the attempt to prepare diluted solutions even at very low temperatures. In case of the ethyl derivative the product (EtPCF2)x is a colourless polymer which on heating (500-600 °C) yields a mixture of dimers (EtPCF2)2 (trans-, cis-1,3- and trans-1,2-diphosphetane; ratio 73:13,5:13,5). 1 and 2 have been used as equivalents of the phosphaalkenes RP=CF2 in one-pot reactions with 2,3-dimethylbutadiene and 1,3-cyclohexadiene, respectively. The labile P=C intermediates pro­duced at 120 °C are captured by the dienes affording the [2+4]-cycloadducts 3-6 in good yields. Oxidation with sulfur gives the corresponding phosphane sulfides 7-10 in almost quantitative yields. New compounds were characterized by spectroscopic (NMR, MS, IR) and analytical methods.
Synthese und Struktur von Trichloro(phthalocyaninato)tantal(V) / Synthesis and Structure of Trichloro(phthalocyaninato)tantalum(V)
Authors: Gingl Franz , Strähle Joachim 
Published: March 2015

Abstract
The reaction of TaCl5 with phthalodinitrile at 240 °C yields TaCl3(pc). It crystallizes in the triclinic space group P1̄ with the lattice constants a = 836.0(2), b = 1207.7(4), c = 1368.8(4) pm, α = 79.86(3)°, β = 93.34(2)°, γ = 100.97(2)°, Z = 2. The structure is closely related to that of triclinic TiCl2(pc). In TaCl3(pc) the Ta atom has the coordination number seven. The plane of the three Cl atoms is parallel to the plane of the phthalocyaninato ligand forming a coordination polyhedron of the type square base - trigonal cap with the symmetry Cs. The distances Ta-Cl range from 237.4 to 246.6 pm and the distances Ta-N from 216.7 to 218.8 pm.
Zur strukturellen Verzerrung von Fe4S4I4
2- -Clustern durch Iod-Iod-Kon Die Kristallstrukturen von (Ph4P)2Fe4S4I4 und (Me3NCH2Ph)2Fe4S4I4 / Structural Distortion of Fe4S4I2
2- Clusters through Iodine-Iodine Contacts: Crystal Structures of (Ph4P)2Fe4S4I4 and (Me3NCH2Ph)2Fe4S4I4
Authors: Pohl Siegfried , Saak Wolfgang 
Published: March 2015

Abstract
The structures of (Ph4P)2Fe4S4I4 (1) and (Me3NCH2Ph)2Fe4S4I4 (2) were determined from single crystal X-ray diffraction data.
1 crystallizes in the tetragonal space group I41/a with a = 1088.3(1) and c = 4540.3(2) pm. Z = 4.
2: Monoclinic, space group Cc. a = 1332.0(2), b = 1513.8(3), c = 1755.1(3) pm, β = 96.69(1)°, Z = 4.
In 1 the anion Fe4S4I4
2- has imposed S4 symmetry with four short (226.2 pm) and eight long (228.1 and 228.4 pm) Fe-S distances parallel and perpendicular, respectively, to the crystallo­graphic 4̃ axis. The Fe-Fe distances were found to be 274.3 and 275.5 pm (Fe-I 254.1 p0m).
In (Me3NCH2Ph)2Fe4S4I4 the [Fe4S4]2+ cluster also exhibits a slightly compressed tetragonal core structure but the core distortions are larger and less regular than in 1 (Fe-S distances from 224.6 to 232.9 pm, Fe-Fe distances from 269.6 to 275.9 pm, Fe-I distances from 249.5 to 255.7 pm).
In addition there are in 2 iodine-iodine interactions between the anions with an I-I distance of 391.7 pm. These weak attractive forces seem to be the reason for the rather large and hitherto in [Fe4S4] clusters with four identical ligands unobserved distortion of the Fe4S4 core.
Crystal Structure and Magnetic Property of the Binuclear Manganese(III) Complex with μ-Acetate and Di-μ-Alkoxo Bridges
Authors: Nishida Yuzo , Oshino Naoko , Tokii Tadashi 
Published: March 2015

Abstract
Binuclear manganese(III) complex, [Mn2L(μ-OCH3)(μ-CH3COO)(OHCH3)]ClO4 was pre­pared and characterized in terms of crystal structure determination, magnetic measurement, and ESR spectroscopy, where H3L represents the Schiff base derived from salicylaldehyde and 1,5- diamino-3-pentanol.
Mercuric Oxide-Iodine Oxidation of 6β-Hydroxypregnanes. Influence of the C-5 Functionality
Authors: Brachet-Cota Adriana L. , Burton Gerardo 
Published: March 2015

Abstract
Oxidation of 6β-hydroxyprogesterone and 3β-acetoxy-5 α,6 β-dihydroxypregnan-20-one with mercuric oxide-iodine under photolytic conditions rendered 4α-iodo-5β,6β-oxidopregnan-3,20-dione and 3β-acetoxy-7-iodo-19-formyloxy-5,7-seco-6-norpregnan-5,20-dione respectively.
Detection of Reactive Sulfur Molecules (S6, S7, S9, S∞) in Commercial Sulfur, in Sulfur Minerals, and in Sulfur Melts Slowly Cooled to 20 °C [1].
Authors: Steudel Ralf , Holz Birger 
Published: March 2015

Abstract
Quantitative analysis by high-pressure liquid chromatography shows that all commercial samples of elemental sulfur besides S8 contain traces of S7 (up to 0.56%) and in some cases also S6, S9 , and polymeric sulfur (S∞). Pure S8 can be obtained by recrystallization from CS2 . Elemental sulfur minerals also quite often contain traces of S7 (up to 0.3%). Since neither irradiation by daylight at 20 °C nor heating to 90 °C for 41 days did convert α-S8 into S7 , the reactive sulfur molecules Sn (n≠8) are believed to origin from liquid or gaseous sulfur which are known to be complex equilibrium mixtures of many Sn species. Sulfur melts slowly cooled (within 0.6 to 145 h) from 122 to 20 °C in fact contain S7 (minimum 0.2%) and at cooling rates of <24 h also other non-S8 molecules. Solid solutions of S7 in α-S8 have also been prepared by cocrystallization of the compounds from CS2. In contrast to pure α-S8, these solid solutions are pale-yellow at 77 K, and the implications of these findings for the surface composition of Jupiter’s satellite Io and for the mechanical properties of “formed sulfur” (Prills, Rotoform, Slates, etc.) are discussed.
Nachweis von Corticosteroiden im Fett von Dachs und Murmeltier / Detection of Corticosteroids in Fat of Badger and of Alp-Marmot
Authors: Wagner H. , Nusser D. 
Published: March 2015

Abstract
In our search for the antiinflammatory activ principles of fat of badger and alp-marmot, used in folk-medicine as remedies against rheumatism and arthritis, eight known corticosteroids have been detected and identified in the lipophilic fraction of body fats of both animals. Enrichment and detection succeeded by using TLC, straight phase HPLC with diode array equipment, HR-GC on OV-1 capillary columns and GC/MS of the methyloxime-trimethylsilylated steroids. The amount of the detected steroids ranges from 30-40 mg/kg. The whole antiinflammatory activity of the fat, as measured in the rat paw edema test, results from these and further hitherto unidentified cortico-steroids.
1,3-Digermapropan und 1,3,5-Trigermacyclohexan / 1,3-Digermapropane and 1,3,5-Trigermacyclohexane
Authors: Schmidbaur Hubert , Rott Johann , Reber Gabriele , Müller Gerhard 
Published: March 2015

Abstract
From the copper-catalyzed reaction of germanium powder with dichloromethane at 350 °C a mixture of alkylchlorogermanes is obtained, in which CH3GeCl3, CH2(GeCl3)2 (1) and (Cl2GeCH2)3 (2) are the major products. Treatment of 1 and 2 with LiAlH4 in di-n-butyl or diethylether, resp., affords the hydrides CH2(GeH3)2 (3) and cyclic (H2GeCH2)3 (4), the latter along with the heterocycle H2Ge(CH2GeH2)2 (5). Compounds 3-5 have been identified by analytical and spectroscopic data, and the crystal structure of 4 has been determined by single crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group Pmn21, with two molecules in the unit cell (a = 8.663(1), b = 7.783(1), c = 6.124(1) Å). The molecules, which are in a chair conformation, have crystallographic mirror symmetry with bond angles slightly larger than tetrahedral and Ge-C distances of 1.944(6), 1.953(3) and 1.955(4) Å. The compounds show potential as substrates for plasma-enhanced chemical vapour deposition (PE-CVD) of amorphous germanium carbon alloys (a-Ge, C:H).
Tetrakis-pentamethylcyclopentadienyl-cyclotetrastiban (PcpSb)4 : Synthese, Molekül-und Kristallstruktur / Tetrakis-pentamethylcyclopentadienyl-cyclotetrastibane (PcpSb)4 : Synthesis, Molecular and Crystal Structure
Authors: Berlitz Theo F. , Sinning Heike , Lorberth Jörg , Müller Ulrich 
Published: March 2015

Abstract
Reaction of SbCl3 with KPcp (Pep = pentamethylcyclopentadienyl) in etheral solution at -78 °C affords dimeric pentamethylcyclopentadiene and orange-red (PcpSb)4 in high yield. 1H, 13 C NMR, IR, UV and mass spectra are reported. The tetrameric structure was found by a crystal structure determination carried out with X-ray diffraction data collected at -50 °C (928 independent observed reflexions. R = 0.055). Crystal data: tetragonal, space group I41/amd, a = 2400.0(5), c = 781.7(5) pm, Z = 4. The (PcpSb)4 molecules have a non-planar Sb4 ring with Sb -Sb bond lengths of 285.6(1) pm, one η1-Pcp ring is attached to each Sb atom. Contrary to the solid state structure, monomeric molecules are found in benzene and hexane solutions.
Tricyclische β-Lactame, VI. Synthese und Struktur von 5,6,6-Trimethyl-2,3-benzo-4-thia-1-azabicyclo- [3.2.0]heptan-7-on, einem neuen β-Lactamgrundgerüst / Tricyclic β-Lactames, VI. Synthesis and Structure of 5,6,6-Trimethyl-2,3-benzo-4-thia-1-aza-bicyclo[3.2.0]heptane-7-one, a New Basicskeleton of β-Lactames
Authors: Santer Gerhard , Ongania Karl-Hans , Hofer Klaus , Gieren Alfred 
Published: March 2015

Abstract
The title compound 1 was prepared by cyclization of the dihydrobenzthiazole-acetic acid 6 and characterized by X-ray structure analysis.
Synthesis of Quaternary Salts from 4,7-Phenanthroline and Dibromoalkanes
Authors: Singh Shyam K. , Summers Lindsay A. , Hick Larry A. 
Published: March 2015

Abstract
4,7-Phenanthroline, Quaternary Salts, Dibromoalkanes 4,7-Phenanthroline reacts with dibromoalkanes to afford 4-bromoalkyl-4,7-phenanthrolinium bromides. 4-(3-Bromo-propyl)-and 4-(4-bromobutyl)-4,7-phenanthrolinium bromides on heat-ing afford the corresponding 4,4'-(alkanediyl)-bis-4,7-phenanthrolinium diquaternary salts whereas 4-(5-bromopentyl)-and 4-(6-bromohexyl)-4,7-phenanthrolinium bromides give the corresponding bridged diquaternary salts which are the first representatives of new heterocyclic ring systems.
Zur Koordination unterschiedlicher Hauptgruppenmetalle mit einem speziellen, chelatisierenden Silazan / On the Coordination of Different Main Group Metals with a Special, Chelating Silazane
Authors: Veith M. , Goffing F. , Huch V. 
Published: March 2015

Abstract
The cis-isomer of the silazane H2L (1) (L = [NtBu][Me]Si(NtBu)2Si[Me][NtBu]) has been used as a ligand to main group metals. By displacing the hydrogen atoms of 1 the compounds L(MgMe)2 (4), L(MgCl)2 (5) and L(Li)(InMe2) (6) have been obtained. According to the 1H NMR spectra the structures of 4-6 are very similar: a polycyclic, cubane-like Si2N4M2 framework results from the special atomic arrangements and from intramolecular Lewis acid-base interactions between the metals M and the nitrogen atoms. Divalent metals and metal-centered groups can also be incorporated into 1. In the latter case a seco norcubane-like polycycle Si2N4M is produced as confirmed by X-ray structure determinations of LGaMe (8) and LSb+ InCl4
- (11). LInMe (7) and LSn (9) seem to adopt the same tricyclic structure as 8, although the 1H NMR spectra are not consistent with a rigid molecule (low symmetry), but rather with a fluxional behaviour (high symmetry). When 5 is allowed to react with sodium/naphthalene in THF part of the magnesium is reduced and LMg(THF)2 (12) is formed. An X-ray structure determination of 12 reveals the compound to be only bicyclic with the magnesium atom coordinated by two nitrogen and two THF oxygen atoms.
Ein weiteres Silicat-Anion: [Si(NCSe)6]2– / A Further Silicate Anion: [Si(NCSe)6]2–
Authors: Heininger Wolfgang , Polborn Kurt , Nagorsen Günter 
Published: March 2015

Abstract
Reaction of SiCl4 with NMe4NCSe or NEt4NCSe in cold acetonitrile leads to the corresponding crystalline salts of the new hexa-coordinate silicon complex anion [Si(NCSe)6]2- (1 ] ; . Their crystallographic data were determined: [NMe4]2[Si(NCSe)6]: rhombohedral. R3̄. a = 897 pm. a = 84.1°. Z = 1. [NEt4]2[Si(NCSe)6], tetragonal modification (from pure acetonitrile): P42/m, a = 1056 pm. c - 1580 pm. Z = 2. [NEt4]2[Si(NCSe)6]. orthorhombic modification (from acetonitrile containing NEt4Cl): a = 1704 pm. b = 1986 pm. c = 1028 pm. Z = 4. N-bonding of the NCSe groups in [Si(NCSe)6]2 is proved by the X-ray structure analysis of [NMe4]2[Si(NCSe)6] and by IR spectra. The concentration dependence of the molar conductance of an acetonitrile solution of [NMe4]2[Si(NCSe)6] was studied. At low concentrations partial dissociation of the hexa-isoselenocyanatosilicate ion is observed.
Flüssigkristalline Kohlenhydratdithioacetale / Liquid Crystalline Carbohydrate Dithioacetals
Authors: Eckert Andreas , Kohne Bernd , Praefcke Klaus 
Published: March 2015

Abstract
S,S-dialkyl acetals of hexanal and numerous aldoses, tripodal in structure, have been synthesized, characterized and investigated by optical microscopy and D.S.C. Most of these geminal dithioacetals show a complicated melting behaviour and are thermotropic liquid crystal-line, exhibiting only one smectic-like phase of identical type. This mesophase is not miscible with the SAd -Phase of other amphiphilic sugar-based liquid crystals. As shown in a homologues series of D-glucose S,S-dialkylacetal derivatives clearing points are rising as function of growing number n of carbon atoms in their S-alkyl chains. With constant n given a similar trend is observed by varying the length of the polar, hydrophilic sugar units. Regarding stereochemistry the dithioderivatives 5 and 12 of the pentose or hexose series, respectively, with a configuration related to that of D-mannose exhibit relatively the most stable mesophase. However, the most stable mesophase of all investigated sugar dithioderivatives is exhibited by the heptose S,S-dialkylacetal 13. Surprisingly, derivative 10 of L-rhamnose (6-desoxy-L-mannose) - the terminal hydroxyl group in the sugar chain of mannose is missing! -showed to be non-mesomorphic, demonstrating that a terminal hydroxyl group of these sugar derivatives seems to be essential for exhibiting a mesophase. On the other hand, as shown with the dithioderivative 9 of 2-desoxy-D-glucose in comparison to the derivative 8e and 12 of D-glucose or D-mannose, respectively, their clearing points seem to be less, although differently effected if an internal hydroxyl group - for instance here at C-2 - has been stripped off.
Melting behaviour as well as thermomesogenic properties of the presented amphiphilic carbo-hydrate liquid crystals in relationship to their molecular structure are discussed in detail.
Notiz über Mono- und Bisaddukte von Diketen an (–)-Menthon / Note on Mono- and Bisadducts of Diketene to (–)-Menthone
Authors: Dehmlow Eckehard V. , Sleegers Arthur 
Published: March 2015

Abstract
1,3-Dioxin-4-ones from Ketones Onium salt and acid catalyzed addition of di-ketene to (-)-menthone gives improved yields of 2 and 3. Excess of diketene leads to diastereomeric mixtures of compounds 4 and 6 from menthone and menthol, respectively.
Di(μ-phosphido)cobalt-und -nickel-Verbindungen mit Trimethylphosphanliganden/ Di(μ-phosphido)cobalt and Nickel Compounds with Trimethylphosphine Ligands
Authors: Klein Hans-Friedrich , Gaß Michael , Zucha Ulf , Eisenmann Brigitte 
Published: March 2015

Abstract
Several fortuitous preparations and high yield rational syntheses for [(Me3P)2M(PMe2)]: (1: M = Co; 2: M = Ni) are described. 1 crystallizes in the space group P1̄ (no. 2); a = 975.6(5). b = 943.6(5), c - 904.2(5) pm. α= 63.8(1)°, β = 79.1(1)°, γ = 72.8(1)°. Mixed metal complexes L2Co(PR2)2NiL2 (L = PMe3; R = Me, Ph) evaded detection giving symmetric products exclusively. An improved synthesis of LiP(C6H5)2·dioxane is also described.