bluuebunny/crossref_metadata_2025 huggingface dataset:
Inverse Perovskites (RE3N)Sn with RE = La, Ce, Pr, Nd, Sm: Preparation, Crystal Structures and Physical Properties
Authors: Kirchner Martin , Schnelle Walter , Niewa Rainer
Published: February 2015

The ternary compounds (RE3N)Sn with RE = La, Ce, Pr, Nd, Sm were prepared starting from the elements. The compounds with RE = La, Ce, Pr were obtained as single phase materials according to X-ray powder diffraction patterns, which also indicate the cubic inverse perovskite crystal structure (space group Pm3̄m, La: a = 509.48(2) pm, Ce: a = 501.59(2) pm, Pr: a = 497.53(2) pm, Nd: a = 494.70(5) pm, Sm: a =488.35(9) pm). Chemical analyses proof the correct composition and particularly the absence of nonmetallic constituents next to nitrogen. All studied compounds show metallic characteristics in the electrical resistivity. Magnetic susceptibility measurements indicate (La3N)Sn to be a Pauli-paramagnet. Initially observed superconductivity was traced down to be due to thin La films on the surface of the grains. The Ce and Pr containing compounds show the behavior of 4f1 ions and 4f2 ions, and order antiferromagnetically at 6.8(2) K and 48(1) K, respectively.
Structural, Magnetic and Electrical Properties of the Ternary Silicide Gd6Co1.67Si3 Derived from the Hexagonal Ho4Co3.07 (or Ho6Co4.61) Type Structure
Authors: Gaudin Etienne , Weill François , Chevalier Bernard
Published: February 2015

The title compound was discovered as an impurity phase in many GdCoSi samples. It crystallizes in the hexagonal space group P63/m with a = 11.7787(5) and c = 4.1640(2) Å . Using X-ray powder diffraction, an ordered distribution between Co and Si was found but one site is not fully occupied by Co for steric reasons. Magnetization measurements reveal that Gd6Co1.67Si3 exhibits a ferromagnetic transition at TC = 294(2) K, a Curie temperature similar to that reported for pure gadolinium. This magnetic ordering has been confirmed by electrical resistivity investigations.
Ba5(Al/Ga)5(Sn/Pb): Neue Verbindungen an der Zintl-Grenze / Ba5(Al/Ga)5(Sn/Pb): New Compounds at the Zintl Border
Authors: Guttsche Kristin , Rosin Angela , Wendorff Marco , Röhr Caroline
Published: February 2015

The new isotypic intermetallic phases Ba5MIII
5MIV (MIII = Al, Ga; MIV = Sn, Pb) have been synthesized from stoichiometric amounts of the elements at maximum temperatures of 900 to 1000 ◦C. They crystallize in the hexagonal space group P6̄m2 (Ba5Al5Sn: a = 605.05(8), c = 1109.0(2) pm, R1 = 0.0137; Ba5Ga5Sn: a = 599.45(5), c = 1086.00(7) pm, R1 = 0.0485; Ba5Al5Pb: a = 606.9(2), c = 1112.0(4) pm, R1 = 0.0409 and Ba5Ga5Pb: a = 601.76(7), c = 1091.51(13) pm, R1 = 0.0295), forming a new structure type. Similar to the Zintl phases Ba2MIV (Co2Si structure type, orthorhombic, space group Pnma; Ba2Sn: a = 861.52(14), b = 569.85(9), c = 1056.9(2) pm, R1 = 0.0217 and Ba2Pb: a = 865.12(13), b = 569.1(2), c = 1061.8(2) pm, R1 = 0.0470), these new ternary phases contain isolated MIV atoms (coordinated by 11 Ba atoms). In addition, sheets of 3- and 4-bonded Al/Ga atoms similar to those in Ba3Al5 are present. In accordance with this, a formal subdivision of Ba5MIII
5MIV into Ba3MIII
5 ・ Ba2MIV can be performed to describe the observed intergrowth or chemical twinning of two different binary intermetallics to give the new ternary compounds. Beyond structural aspects, also the nature of the chemical bonding (as studied by FP-LAPW calculations) in these new, non-electron precise compounds in the vicinity of the Zintl border can be interpreted in this vein.
Synthese und Kristallstruktur von Pt2Sn2Zn3, der ersten ternären Verbindung im System Pt/Sn/Zn / Synthesis and Crystal Structure of Pt2Sn2Zn3, the First Ternary Compound of the Pt/Sn/Zn System
Authors: Lux Rainer , Hillebrecht Harald
Published: February 2015

Single crystals of Pt2Sn2Zn3, the first ternary compound in the system Pt/Sn/Zn, have been synthesised from the elements. Pt2Sn2Zn3 exhibits a new structure type (hP14, P63/mmc, Z = 2, a = 4.3367(5), c = 15.532(3) Å , 402 reflections, 14 variables, R1(F) = 0.025, wR2(I) = 0.059) with motifs of the binary compounds. One Pt atom has a cubic environment (PtSn6Zn2), the second one forms an Edshammer polyhedron (PtSn2Zn9). Pt2Sn2Zn3 is one of the few examples of a ternary Sn/Zn compound of a transition metal.
Au3SnCuP10 and Au3SnP7: Preparation and Crystal Structures of Au3Sn Heterocluster Polyphosphides
Authors: Lange Stefan , Nilges Tom
Published: February 2015

The formation of Au3Sn heteroclusters completes the homologous series of M3Sn clusters observed for transition metal main-group polyphosphides. Au3SnCuP10 is cubic, space group F4̅3̅m (No. 216) with lattice parameter a = 10.3953(5) Å . The structure refinement yielded R1 = 0.0353 and wR2 = 0.0726 for 154 F2 values and 13 variables. Disordered Au3Sn heteroclusters occupy all octahedral, and adamantane like P10 cages one half of the tetrahedral voids of a face-centred cubic ( fcc) arrangement of copper. Ordered and orientationally disordered Au3Sn heteroclusters have been observed for Au3SnP7, embedded in a 1
∞ [P7] polyphosphide unit formed by six-membered phosphorus rings in chair conformation which are linked by a P-bridge. Au3SnP7 is monoclinic, space group P21/m (No. 11) with lattice parameters of a = 6.219(2), b = 10.836(2), c = 6.318(2) Å , β = 108.65(2)°, V = 403.4(2) Å3, R1 = 0.0412 and wR2 = 0.0745, 1261 F2 values and 56 variables. Au3SnP7 with disordered Au3Sn clusters has slightly larger lattice parameters of a = 6.343(3), b = 10.955(3), c = 6.372(3) Å , β = 108.63(2)°, V = 419.6(2) Å3, R1 = 0.0324 and wR2 = 0.0691, 1131 F2 values and 58 variables.
Alternativ-Liganden, XXXVII. Phosphanliganden mit Bor als Lewis-acidem Zentrum: Synthese und Koordinationseigenschaften / Alternative Ligands, XXXVII. Phosphane Ligands with Boron as Lewis-acidic Centre: Synthesis and Coordinating Properties
Authors: Grobe Joseph , Lütke-Brochtrup Kai , Krebs Bernt , Läge Mechtild , Niemeyer Hans-Hermann , Würthwein Ernst-Ulrich
Published: February 2015

The complex [Rh(CO)Cl{Me2PC(Me)=C(Me)BMe2}2] (5) has been prepared again in order to prove its structure with weak bonding interactions between the basic rhodium centre and the Lewisacidic Me2B group of the donor/acceptor ligand Me2PC(Me)=C(Me)BMe2 (1). For further investigations additional ligands with P-donor and B-acceptor centres, e. g. Ph2PC(Ph)=C(Ph)BPh2 (2), B(OCH2PMe2)3 (3), and B(CH2CH2PMe2)3 (4), have been prepared and the coordinating properties have been studied by reactions of 1 and 4 with [(π-C5Me5)Rh(CO)2] and Pd(PPh3)4, respectively. Because single crystals of the products [(π-C5Me5)Rh(CO)Me2PC(Me)=C(Me)BMe2] (6), [(π-C5Me5)Rh(CO){Me2PC(Me)=C(Me)BMe2}2] (7) as well as [Pd{B(CH2CH2PMe2)3}] (8) or [(Ph3P)Pd{B(CH2CH2PMe2)3}] (9) could not be generated, quantum chemical calculations have been used to elucidate the coordination geometry expected for 5, 8 and 9. The calculations support the structure of 5 within the expected limitations of the experimental and theoretical methods and - in spite of the extremely soft coordination sphere of 8 and 9 - are in accord with spectroscopic results for the cage structures.
Cs2K2[Pt12O8(SO4)12]: A New Oxide-Sulfate with the Cluster Anion [Pt12O8(SO4)12]4–
Authors: Pley Martin , Wickleder Mathias S.
Published: February 2015

Single crystals of Cs2K2[Pt12O8(SO4)12] (R3̄, Z = 3, a = 1198.9(3), c = 2768.9(9) pm, Rall = 0.1154) were obtained by the reaction of Cs2[Pt(NO2)4], K2[Pt(NO2)4] and conc. sulfuric acid at 400 °C in a sealed glass ampoule. The compound contains the cluster anion [Pt12O8(SO4)12]4−. It consists of six Pt2
6+ dumbbell shaped cations that are linked by eight oxide ions and twelve sulfate anions to form a distorted Pt12 icosahedron. The arrangement of the cluster anions in the crystal structure provides two voids for the cations. The larger one is occupied by the Cs+ ions while the K+ ions reside in the smaller one. For the Cs+ ions the coordination number is 15 while the K+ ions have a coordination number of 13.
Tetrakis(Triphenylphosphine Oxide)Lithium Di(Iodo)Aurate(I)
Authors: Schuster Oliver , Schmidbaur Hubert
Published: February 2015

The title compound, [(Ph3PO)4Li]+ AuI2
−, crystallized from a reaction mixture obtained from Ph3PAuC≡CPh, LiMe and MeI (molar ratio 1 : 1 : 2) in diethylether upon subsequent oxidation in air. The triclinic crystals, space group P1̅, are isomorphous with those of the corresponding di(bromo)cuprate(I). The gold atoms of the two independent [AuI2]− anions reside on centers of inversion and have no close interanionic contacts. The structure of the complete [(Ph3PO)4Li]+ cation does not approach any standard symmetry (e. g., S4 or D2d). Its conformation is similar to that reported for the isomorphous reference compound with the anion CuBr2 −, but different from that in the bromide・ acetonitrile, Li-phthalocyaninate or iodide ・ triphenylphosphine oxide salts, suggesting that the relative orientation of the four Ph3PO molecules at the Li+ center is flexible and co-determined by the packing in the crystals. Even the O4Li core units are affected by the variations in the mode of attachment of the Ph3PO ligands, and their distortions are significant as shown by the ranges of Li-O distances and O-Li-O angles, which are small in the title compound, but spread from 1.886(5) to 1.953(9) Å and from 105.1(4) to 111.8(4)◦, respectively, when taking into account all known salts with the [(Ph3PO)4Li]+ cation
(Phenylethynyl)Trimethylphosphonium Bromide And Bromoaurates(I)
Authors: Schuster Oliver , Schmidbaur Hubert
Published: February 2015

(Phenylethynyl)trimethylphosphonium bromide (1) has been reinvestigated by NMR spectroscopy and its crystal structure determined. In the monoclinic crystals, the cations are arranged in layers in the a-c planes, with their P-C≡C-Ph axes parallel within one layer, but alternating in consecutive layers. The bromide anions are accommodated in channels between the cations. The spectroscopic and structural results are in agreement with the special reactivity pattern documented for ethynylphosphonium salts, in particular with the sensitivity to nucleophiles which e. g. prevents standard ylide formation. A slurry of polymeric phenylethynylgold [PhC≡CAu]n in dichloromethane reacts with [Me3PC≡CPh]Br to give a clear solution of [Me3PC≡CPh]+ [PhC≡CAuBr]− (2). In a similar reaction, with soluble pentafluorophenylgold(tetrahydrothiophene), C6F5Au(tht), the salt [Me3PC≡CPh]+ [C6F5AuBr]− (3) is produced. All attempts to generate gold(I) complexes of the corresponding phosphonium ylide [Me2(PhC≡C)P=CH2] by treatment of the two phosphonium salts (2, 3) with strong base were not successful owing to side reactions induced by base
Characterization Of Structure Types By Lattice Complexes With Increased Self-Coordination Numbers
Authors: Hauck Jürgen , Mika Klaus
Published: February 2015

Most of the 402 characteristic Wyckoff positions were analyzed for the numbers 1, 2, 3, etc. of lattice complexes with increased self-coordination numbers Ti of the i = 1 - 3 shells. The Wyckoff letters of standardized inorganic structures with the proper space group number get an additional number 1, 2, 3, etc., if the x, y, z, c/a, cos γ , etc. parameters are close to the parameters of these lattice complexes. The lattice complexes 1, 2, 3, etc. or combinations of several of these complexes are sphere, layer or rod packings. The plate- or needle-like habit of single crystals can frequently be correlated with layered or rod-like packings. Combinations of lattice complexes can be analyzed for attractive or repulsive interactions by structure maps
Thermal Evolution Of The “Mouse Fur” Of Fibrous Aluminium Oxide/Hydroxide Formed On Amalgamated Aluminium Upon Reaction With Moist Air
Authors: García-García F. Javier , Kienle Lorenz
Published: February 2015

Nano-fibres of amorphous aluminium oxide/hydroxide have been obtained via reaction of amalgamated aluminium with moist air. Thermal transformation of the as prepared sample was followed by X-ray powder diffraction and electron microscopy techniques. Crystallisation of γ -Al2O3 nanocrystals inside the amorphous fibres starts at 400 °C and the maximum crystal size is achieved at 700 - 800 °C. The fibrous transition alumina matrix transforms into a sponge-like morphology between 800 and 900 °C. Annealing at higher temperature results in the condensation into large globular α-Al2O3 crystals. The entire γ - to α-Al2O3 transformation occurs via two consecutive steps of coalescence and explosive character, respectively. The direct contact between transition alumina crystals governs the transformation. The presence of some other transition alumina is inferred from high resolution electron microscopy studies, and antiphase boundaries in {111} of the spinel type structure for γ -Al2O3 obviously determine the crystallographic path between them
Synthesis, Calorimetric Study, Infrared Spectroscopy And Crystal Structure Investigation Of β-[Tetraethylammonium Tetramethylammonium Tetrachlorozincate(II)] [β]-[(C2h5)4N][(Ch3)4N]Zncl4
Authors: Hlel F. , Rheim A. , Guerfel T. , Guidara K.
Published: February 2015

Synthesis, crystal structure and infrared description are reported for a new phase of tetraethylammonium tetramethylammonium tetrachlorozincate(II) β -[(TEA)(TMA)ZnCl4]. Calorimetry study shows five endothermic picks at 165, 232, 280, 284, and 377 K. The compound crystallizes in the orthorhombic system, space group P21212 (No 18), with Z = 4 and a = 13.099(3), b = 13.119(2) and c = 11.812(3) Å . The crystal structure consists of alternate organic-inorganic [(TMA)+/ZnCl4
2−] layers and organic sheets (TEA)+. Organic and inorganic groups are not disordered. Its main geometrical features are those commonly observed in the atomic arrangements of (TEA)2ZnCl4 and (TMA)2ZnCl4
Synthesis And Antimicrobial Activity Of Some Annelated Quinazoline Derivatives
Authors: Aly A. A.
Published: February 2015

A highly efficient and versatile synthetic approach to the synthesis of annelated quinazoline derivatives viz. 3,4,9,10a-tetraazaphenanthrenes 5 - 7, thiazolidinylquinazoline 9, 2,4,9,10a-tetraazaphenanthrene 11, quinazolino[4,3-b]quinazolin-8-one 12 and imidazoquinazolines 14a,b, 15. Also, a variety of pyrazolylquinazolines 19 - 21, pyrimidinylquinazolines 22a,b were obtained via a sequence of heterocyclization reactions of 4-methyl-N-[4-(4-oxo-3,4-dihydroquinazolin-2-yl)phenyl]benzenesulfonamide (2) with different reagents. The new compounds were synthesized with the objective of study their antimicrobial activity
Reaktionen Von Acetylencarbonsäureestern Mit Piperazinderivaten
Authors: Möhrle Hans , Azodi Katja
Published: February 2015

Hg(II)-EDTA-dehydrogenation of benzylpiperazine (5) in 50% ethanol with addition of diethyl acetylenedicarboxylate (2) to a minor extent gives rise to (piperazine-1,4-diyl)-bis(maleate) (9), which is inert to Hg(II)-EDTA and results in quantitative yield when Hg(II)-EDTA is omitted. 4- Benzylpiperazin-1-yl)-monomaleate (8) reacts with 2 in various solvents by addition of water with dealkylation and formation of 9. CH-acidic compounds may also be used as proton donors. Analogous reactions, although with minor yields, occur with the propiolates 11 and 12. 1-Substituted piperazines with benzyl, methine or allylic groups (5 -5c, 27d - g, and 27h) react readily with acetylenedicarboxylic acid esters to give compounds of type 9, whereas benzhydryl, aromatic and most of the unbranched aliphatic substituents are not replaced. The reactivity of 1,4-disubstituted piperazines corresponds largely to the behaviour of the substituents in the monosubstituted derivatives
Microbial Metabolism Of (+)-Cycloisolongifol-5β-Ol
Authors: Choudhary Muhammad Iqbal , Kausar Waseem , Siddiqui Zafar Ali , Rahman Atta-ur
Published: February 2015

Microbial transformation of a cyclic sesquiterpene, (+)-cycloisolongifol-5β -ol (1), was carried out with the fungus Cunninghamella elegans, resulting in three new metabolites, cycloisolongifol-3β , 5β -diol (2), cycloisolongifol-5β -ol-11-one (3), and cycloisolongifol-3β , 5β , 11α-triol (4). The structures of new compounds were deduced on the basis of spectroscopic evidences
Rb2P2S6 – A New Alkali Thiophosphate: Crystal Structure and Vibrational Spectra of Rubidium Hexathiodiphosphate(V)
Authors: Gjikaj Mimoza , Ehrhardt Claus , Brockner Wolfgang
Published: February 2015

Single crystals of rubidium hexathiodiphosphate(V), Rb2P2S6, have been obtained and investigated by single crystal X-ray diffraction, and IR/FIR and Raman spectroscopy. The title compound crystallizes isotypically to the potassium, caesium and thallium analogues in the orthorhombic space group Immm (no. 71) with a = 8.485(3), b= 6.953(3), c =9.259(3 Å , and Z = 2, final R1= 0.0579 and wR2 = 0.0987. The crystal structure is characterized by discrete [P2S6]2− anions (edge-sharing double-tetrahedra) with D2h symmetry. Rubidium is coordinated by ten sulfur atoms forming a slightly distorted two-capped tetragonal prism with a coordination number CNRb 10. The FT-Raman and FT-IR/FIR spectra have been recorded and a factor group analysis was carried out.
Synthesis, Spectroscopic and X-Ray Structure Characterisation of Bis(tetramethylammonium), Bis(tetraethylammonium) and Bis(tetrapropylammonium) Tetrathiotungstates
Authors: Poisot Martha , Näther Christian , Bensch Wolfgang
Published: February 2015

The three new tetraalkylammonium tetrathiotungstates ((Me)4N)2[WS4] (1), ((Et)4N)2[WS4] (2) and ((nPr)4N)2[WS4] (3) were prepared via a direct salt substitution using (NH4)2[WS4] as starting material. Compound 1 crystallises in the chiral orthorhombic space group P212121 with a = 8.9433(4), b = 15.5658(9) and c = 37.279(2) Å . Compound 2 crystallises in space group P21/n with lattice parameters a = 16.6695(12), b = 9.3415(6), c = 16.9965(13) Å and β = 117.185(15)°. The third compound 3 crystallises in space group C2/c with the lattice parameters a = 32.440(2), b = 13.8453(6), c = 15.0563(10) Å and β = 109.19(7)°. The structures of all compounds consist of slightly distorted [WS4]2− tetrahedra and tetraalkylammonium cations which are packed in different ways. One interesting observation is that the disorder of parts of the alkyl groups decreases with increasing chain length. The IR and Raman spectra show the vibrations of the [WS4]2− tetrahedron with a slight shift with increasing alkyl chain length. The most prominent IR-band of the [WS4]2− tetrahedra is broad but not split, indicating that the distortion of the tetrahedra is small.
Metal Tetrahydroborates and Tetrahydroborato Metallates, 30 [1]. Alkoxo-Substituted Alkali Metal Tetrahydroborates: Studies in Solution and Structures in the Solid State
Authors: Knizek Jörg , Nöth Heinrich , Warchhold Markus
Published: February 2015

Reactions of MBH4 (M = Li, Na, K) with tBuOH, Ph3COH, PhOH, F5C6OH, and 2,4- tBu2C6H3OH in THF in a 1 : 1 ratio were followed by 11B NMR spectroscopy. No M[H2B(OR)2] species could be detected, but minor amounts of M[H3BOR] and larger amounts of M[HB(OR)3]. In the reaction of LiBH4 with 2,4-tBu2C6H3OH also a fair proportion of (RO)2BH was generated. The perfluorophenolato borane (F5C6O)2BH·THF was prepared from the phenol and BH3 ·THF in THF solution. It is unstable to disproportionation. Compound (C6F5O)3B·THF was isolated and its crystal structure determined. Reaction of LiBH4 with F5C6OH in hexane generated a solid that proved to be Li[H2B(OC6F5)2]. It is unstable in THF. On the other hand, 2,2’-dihydroxydiphenyl in the presence of secondary amines reacts to give Li[C12H8O2B(NR2)2] (3 - 5). Li[B(O2C12H8)2], 2, is formed when HN(tBu)Ph is used as a secondary amine. The unstable phthalatoborane H{C6H4[C(O)O]2}BH·THF (7), is stabilized as its pyridine adduct (phth)BH·py (8). 7 reacts with 3 equivalents of LitBu to give [Li(HBtBu)3] (11), isolated as its tris(THF) solvate. Analogously, 7 reacts with LiNMePh to produce compound Li[HB(NMePh)3] (10). Similarly, 7 and NaOtBu (molar ratio 1 : 3) give access to Na[HB(OtBu)3] (9). In attempts to grow single crystals, specimens resulting from a hexane solution showed that partial hydrolysis has occurred to give Na[HB(OtBu)3]·Na[(tBuO)2BO]·Na[tBuOB(O)H], which crystallizes as a centrosymmetric dimer. While catecholborane when treated with LitBu in THF and DME gave access to (dme)2Li[catB- (tBu)2], 12 (dme)2, several compounds were observed when Li piperidide was used as nucleophile. Amongst these, the most interesting one was (dme)(THF)Li2(cat)(catBH), 13 (dme)THF, the crystal structure of which was determined. In all cases where the borate species carried OR groups the O atoms of the RO or PhO group coordinate with the alkali metal cation. DFT calculations for the series of anions H4−nBXn
− showed that HBX3
− is the most stable species for X = F, OH, NH2. This confirms experimental results.
A New Acyclic Diterpene Glycoside from Nicotiana attenuata with a Mild Deterrent Effect on Feeding Manduca sexta Larvae
Authors: Jassbi Amir Reza , Zamanizadehnajari Simin , Kessler Danny , Baldwin Ian T.
Published: February 2015

To investigate the role of secondary metabolites in the feeding behavior of Manduca sexta larvae feeding on Nicotiana attenuata, an aqueous acetone extract of the aerial parts of the plant was subjected to feeding-performance bioassay-guided fractionation. We isolated three 20- hydroxygeranyllinalool glycosides from the leaves of N. attenuata, which acted as mild deterrents to the feeding herbivore M. sexta. One of the diterpenoid glycosides, attenoside (3), is a novel natural product. The structures of the compounds were determined using APCI mass spectrometry and 1- and 2D-NMR spectroscopy.
New Withanolides from Fresh Berries of Withania somnifera
Authors: Lal Payare , Misra Laxminarain , Sangwan Rajender S. , Tuli Rakesh
Published: February 2015

The chloroform extract of the fresh berries of Withania somnifera has been investigated to afford stigmasterol, its glucoside, withanone, 27-hydroxy withanolide A along with two new withanolides, namely, iso-withanone (1) and 6α,7α-epoxy-1α,3β ,5α-trihydroxy-witha-24-enolide (2). Compound 1 possesses an uncommon 17α-oriented side chain whereas compound 2 has 1α,3β - dihydroxy group which is a molecule of biogenetic significance for withasteroids.
Triterpenoid Saponins from Astragalus corniculatus
Authors: Krasteva Ilina , Nikolov Stefan , Kaloga Maki , Mayer Gisela
Published: February 2015

Two new triterpenoid saponins were isolated from the ethanolic extract of the aerial parts of Astragalus corniculatus Bieb. The structures of the saponins were elucidated as 3β -O-[O-4-oxopentopyranosyl-( 1 → 2)-β -D-glucopyranosyl]-21α-hydroxyolean-12-ene-28-oic acid (1) and 21α- hydroxyolean-12-ene-28-oic acid 3β -4-oxo-pentopyranoside (2) by chemical and spectral methods.
A New Pigment from the Fruiting Bodies of the Basidiomycete Lactarius deliciosus
Authors: Yang Xiao-Long , Luo Du-Qiang , Liu Ji-Kai
Published: February 2015

A new purple azulene pigment (1) was isolated from the fruiting bodies of the basidiomycete Lactarius deliciosus together with one known pigment (2). The structures of the pigments were established on the basis of spectral evidence (MS, IR, 1D- and 2D-NMR experiments).
The Synthesis, Characterization and Structural Analysis of a Co(III) Complex of 1,10-Phenanthroline and Perfluorosebacic Acid, [Co(HL)(phen)2(H2O)]L·H2O
Authors: Kani Ibrahim , Büyükgüngör Orhan , Şişman Filiz
Published: February 2015

The hexacoordinated mononuclear Co(III) complex 1, [Co(HL)(phen)2(H2O)]L·H2O, with the mixed ligands (H2L = HO2C(CF2)8CO2H and 1,10-phenantroline) has been synthesized and characterized by elemental analysis, IR and UV/vis spectroscopy, magnetic susceptibility, TG analysis and X-ray diffraction techniques. The Co(III) atom is coordinated asymmetrically by two bidentate 1,10 phenanthroline ligands, one hydrogencarboxylate ligand, (O2C(CF2)8CO2H)−, and one water molecule. In the crystal structure, there are also dicarboxylate anions and one water molecule attached through hydrogen bonds. Intermolecular π-π interactions between the adjacent phenanthroline ligands also support the packing of the components.
Synthesis, Spectral and Thermal Studies, and Crystal Structure of cis-Bis(4-methylimidazole)bis(picolinato)copper(II) [Cu(pic)2(4-MeIm)2]
Authors: Heren Zerrin , Keser Cem , Ersanli C. Cüneyt , Yeşilel O. Zafer , Ocak Nazan
Published: February 2015

The mixed-ligand picolinato (pic) complex of Cu(II) with 4-methylimidazole (4-MeIm), [Cu(pic)2(4-MeIm)2], was synthesized and characterized by elemental analysis, magnetic susceptibility, spectroscopic methods (UV/vis and FT-IR) and X-ray diffraction. In the slightly distorted octahedral cis-bis(4-methylimidazole)bis(picolinato)copper(II) complex, the pic ligands are coordinated to the Cu(II) ion as bidentate N,O-donors forming chelate rings. The 4-MeIm ligands are N-coordinated in cis positions. The complex crystallizes in the triclinic space group p̅1 with unit cell parameters a = 9.204(5), b = 9.498(5), c = 13.095(5) Å , α = 90.395(5), β = 101.687(5), γ = 112.291(5)° and Z = 2. Hydrogen bondings and C-H ··· π interactions occur between picolinato and methylimidazole ligands of neighboring complex molecules. The thermal decomposition of the complex is described.
Atom Transfer Rearrangement Radical Polymerization of Diamminebis( 2,4,6-trihalophenolato)copper(II) Complexes in the Solid State
Authors: Gökaǧaç Gülsün , Sonsuz Muammer , Şen Fatih , Kısakürek Duygu
Published: February 2015

The synthesis of the poly(dichloro- or dibromophenylene oxide)s was achieved by the thermal decomposition of diammine-bis(2,4,6-trihalophenolato)copper(II) complexes in the solid state by atom transfer rearrangement radical polymerization. The thermal decomposition was performed either at different temperature ranges, 110 - 250 °C, for 3 h, or at the maximum conversion temperature for different time intervals, 3 - 48 h. Maximum yields of polymers were obtained at 190 °C and 3 h. The polymers were characterized by FTIR, 1H and 13C NMR spectroscopy, SEM, TGA and molecular weight determination by viscometrical methods. All the polymers were rigid, having high Tg values between 178 and 189 °C. Only small amounts of Cu were detected by AAS.
Synthesis, Crystal Structure, Spectral and Thermal Studies of a New Organic-Inorganic Hybrid Cobalt(II) Complex of 2,2’-Bipyridine and Nitrate with Squarate
Authors: Yeşilel Okan Zafer , Pasaoglu Hümeyra , Kaştaş Gökhan , Ölmez Halis , Büyükgüngör Orhan
Published: February 2015

The [Co(NO3)(bipy)2](sq)1/2 ・4H2O complex (I) (bipy: 2,2’-bipyridine, sq2−: squarate) has been prepared and characterized by elemental analysis, IR, UV/vis spectra, thermal analysis, and single crystal X-ray diffraction. The title compound crystallizes in the triclinic system, space group p̅1, with a = 7.6302(9), b = 12.0426(15), c = 14.2271(14) Å , α = 107.252(9)◦, β = 98.755(9), γ = 103.363(9)° and Z = 2. The Co(II) ion in its octahedral complex is chelated by the nitrogen atoms of the two 2,2’-bipyridine, and by two oxygen atoms of the nitrato group. The anionic squarate behaves as a counter ion. Thermal analysis has shown that the title compound decomposes in three stages over the range 20 − 1000 °C on heating in a static air atmosphere. The final decomposition product is CoO.
Echinolactones C and D: Two Illudalane Sesquiterpenoids Isolated from the Cultured Mycelia of the Fungus Echinodontium japonicum
Authors: Suzuki Shinsuke , Murayama Tetsuya , Shiono Yoshihito
Published: February 2015

Echinolactones C and D, two compounds with an illudalane sesquiterpenoid skeleton, were isolated from the cultured mycelia of the basidiomycetous fungus Echinodontium japonicum (Echinodontiaceae). The structures of echinolactones C and D were determined by 1D and 2D NMR spectroscopy. Their biological activities were determined using antimicrobial activity and lettuce seedling assays.
Secondary Metabolites from Asphodelus aestivus
Authors: Çalış Ihsan , Birincioǧlu S. Serap , Kırmızıbekmez Hasan , Pfeiffer Bernhard , Heilmann Jörg
Published: February 2015

Together with ten well known compounds, the quinic acid derivative chlorogenic acid, the nucleoside adenosine, two amino acids, tryptophan and phenylalanine, the anthraquinone derivatives, aloemodin, aloemodin acetate and chyrosphanol 1-O-gentiobioside, the flavon C-glycosides, isovitexin, isoorientin and isoorientin 4’-O-β -glucopyranoside, as well as two new acylated isoorientin derivatives, 6”-O-(malonyl)-isoorientin and 6”-O-[(S)-3-hydroxy-3-methylglutaroyl]-isoorientin, were isolated from the water soluble part of the methanolic extract of the fresh leaves of Asphodelus aestivus. All compounds were structurally identified by spectroscopic methods, including UV, MS, and NMR (1D and 2D) spectroscopy. Among the compounds isolated, chlorogenic acid and isoorientin were found to be the main compounds of the methanolic extract.
New Silica Supported Titanium Dioxide Catalysts: Characteristics and Photocatalytic Efficiency in Waste Water Depollution
Authors: Kamil Noureddine , Amrani Mohamed Khalid El , Benjelloun Najiba
Published: February 2015

Silica gel supported titanium dioxide photocatalysts were prepared by sintering TiO2/SiO2 mixtures under variations of TiO2 content, calcination temperature and calcination time. The method allowed to obtain catalyst samples, which can be used in aqueous suspension and which were found to be easily separated by decantation after the photocatalytic treatment. The photocatalytic efficiency of the catalysts was tested by carrying out the photooxidation of the textile dye Acid Red 88 (AR88) in aqueous solution, used as “model” water pollutant. The obtained photoefficiency results were correlated to catalyst physicochemical characteristics, as determined by Inductively Coupled Plasma (ICP) analysis, X-ray diffraction, specific surface area (BET) and scanning electron microscopy (SEM). No positive correlation has been observed between titanium dioxide content and photocatalytic efficiency. The decrease of photocatalytic activity at high calcination temperature (1000 °C) is attributed to the phase transition anatase/rutile as well as to the decreasing specific surface area. According to SEM analysis, no significant fixation of TiO2 on silica is observed for catalysts prepared at low temperature (400 °C). The observed photocatalytic activity is consequently due to free TiO2 particles. The best efficiency is observed for photocatalyst prepared at 800 °C and containing around fifty percent titanium dioxide.
Synthesis and Structure of a Novel Tetranuclear Copper(II) Resorcin[4]arene-based Complex
Authors: Wu Fang-Hui , Liu Yu-Jie , Liu Shu-Qun , Zhang Qian-Feng
Published: February 2015

The preparation, spectroscopic properties and crystal structure of a tetranuclear copper(II) resorcin[4]arene-based complex with the cap-bpa ligand [cap = resorcin[4]arene-based cavitand, bpa = bis(pyridyl)methylamine] are reported. The orientation of each (bpa)Cu fragment in the complex is perpendicular to the cap bowl. All four copper centers are only coordinated to the tridentate bpa moiety.
Protonen on Tour – DFT-Studie zur H+-Wanderung in [1.1.1]- und [2.2.2]-Cryptanden / Protons on Tour – DFT-study of H+-Migration in [1.1.1]- and [2.2.2]-Cryptands
Authors: Puchta Ralph , Galle Michael , Eikema Hommes Nico J. R. van
Published: February 2015

DFT-calculations (RB3LYP/LANL2DZp) show that the migration of a proton inside [1.1.1]- and [2.2.2]-cryptand from one nitrogen atom to the other follows different paths. While the proton in [H⊂1.1.1]-cryptand moves via an ether oxygen atom (activation energy: 19.2 kcal/mol), the proton in [H⊂2.2.2]-cryptand moves directly from one nitrogenatom to the other (activation energy: 16.1 kcal/mol). Our calculations rule out the application of doubly protonated [2.2.2]-cryptands as anion hosts.
Transformation of a Pyrazolidene into a Tetrahydropyrimidinylidene Ligand by Deprotonation/Reprotonation
Authors: Szesni Normen , Weibert Bernhard , Fischer Helmut
Published: February 2015

In an unusual ring enlargement reaction the heterocyclic ligand in a pentacarbonyl(pyrazolidene) chromium complex is transformed in high yield into the corresponding tetrahydropyrimidinylidene ligands by a deprotonation/protonation (or deprotonation/alkylation) sequence.
Third-order Nonlinear Optical Properties of Copper(II)bis{2-[(4-iodophenyl)iminomethyl]-6-methoxy-phenolate}
Authors: Yaglioglu Halime G. , Karakaş Asli , Ünver Hseyin , Elmali Ayhan
Published: February 2015

Copper(II)bis{2-[(4-iodophenyl)iminomethyl]-6-methoxy-phenolate} has been synthesized, characterized by UV-visible spectroscopy, and its crystal structure determined by X-ray diffraction. The Cu atom is situated on a twofold axis and the geometry around the metal centre can be described as distorted square planar with a trans configuration. The absorption maxima are shorter than 450 nm, giving rise to good optical transparency in the visible and near IR. To reveal the microscopic thirdorder NLO properties, the static second hyperpolarizabilities have been evaluated by using the ab initio time-dependent Hartree-Fock (TDHF) method. According to the results, the title complex exhibits non-zero γ values, implying microscopic third-order NLO behavior.
Photolytisch induzierte Reaktionen von CpCo(CO)2(Cp = C5H5, C5H4Me, C5Me5 und C5Ph5) mit Thiiran zu dinuklearen 1,2-Ethandithiolato-S-S-Komplexen / Photolytically Induced Reactions of CpCo(CO)2 (Cp = C5H5, C5H4Me, C5Me5 and C5Ph5) with Thiirane Yielding Dinuclear 1,2-Ethanedithiolato-S,S Complexes
Authors: Drobnik Stefan , Stoll Carola , Nöth Heinrich , Polborn Kurt , Hiller Wolfgang , Lorenza Ingo-Peter
Published: February 2015

The complexes CpCo(CO)2 (Cp = C5H5, C5H4Me, C5Me5 and C5Ph5) (1a - d) react with thiirane C2H4S under UV-irridiation in THF to form the dinuclear μ2-1,2-ethanedithiolate-S,S complexes [(CpCo)2(μ2-S2C2H4)] (2a - d) as main products. Using column chromatography, in case of Cp = C5H5Me also the dimeric complex [C5H4MeCo(μ2-S2C2H4)]2 (3b), in case of Cp = C5Ph5 the mixed disulfido-sulfido complex [(C5Ph5Co)2(μ2-S2)(μ2-S)] (4d) were isolated in small yields. Only 2a reversibly adds SO2 gas to form the μ2-SO2 complex [(C5H5CoSCH2)2(μ2-SO2)] (5a). A bromo ligand bridging the Co atoms can be introduced by the reaction of [(C5Me5CoBr2)]2 (6c) with 1,2-ethanedithiol which gives the cationic complex [(C5Me5CoSCH2)2(μ2-Br)]2CoBr4 (7c). All compounds have been characterized by their IR, 1H and 13C NMR and MS spectra and compounds 2b - d, 3b and 7c by X-ray structure analyses, which prove the pseudo tetrahedral skeleton (CpCoS)2 and the ethane bridge between both sulfur atoms. 3b shows, however, a new unsymmetrical bonding mode of both dithiolato bridges with η1-S und μ2-S ligand functions.
Structure of Bis(isobutylammonium) Selenite and its Sesquihydrate
Authors: Wiechoczek Maren , Jones Peter G.
Published: February 2015

Isobutylammonium selenite and its sesquihydrate were obtained in low yields by reaction of selenium dioxide with the neat amine in the presence of small amounts of water. Both structures were determined by X-ray methods and proved to contain two independent formula units. In both cases, layer structures [(CH3)2CHCH2NH3]2[SeO3] are formed in which all NH hydrogen atoms act as single hydrogen bond donors, and all selenite oxygen atoms accept two hydrogen bonds. The layers contain six independent rings; the anhydrous substance has all rings of graph set R3
4 (10), whereas the sesquihydrate has two each of R4
4 (12), R2
4 (8) and R3
4 (10). The three independent water molecules of the sesquihydrate attach themselves to the layer structure by further classical hydrogen bonds to the selenite oxygen atoms.
Thermolysis of Some Spirobenzopyran-3’,2-[1,3,4]oxadithiino- [5,6-c]benzopyran-4’-ones in the Presence of Some Homodienes and Crystallographic Studies of Some Adducts
Authors: Hegab Mohamed I. , Moustafa A. M.
Published: February 2015

The very reactive α-oxo-thioketone derivatives 2a - d, generated via thermolysis of spirobenzopyran- 3’,2-[1,3,4]oxadithiino[5,6-c]benzopyran-4’-ones 1a - d, reacted with 2,3-dimethyl-1,3-butadiene and 1,3-cyclohexadiene under [4+2]-cycloaddition to afford spirobenzopyran-3’,6-thiapyran-4’-one adducts 3a - d and spirobenzopyran-3’,3-thiabicyclo[2.2.2]oct-5-en-4’-one adducts 4a - d, respectively. On the other hand, the reaction of α-oxo-thioketones 2a - d with isoprene afforded regioselectively only 3-methyl-thiapyran derivatives 5a - d. Single crystal X-ray diffraction studies of 4b, 4c, and 5a give a good support for the established structure.
Synthesis and Crystal Structure of Schiff Bases Based on AMTTO (AMTTO = 4-Amino-6-methyl-3-thio-3,4-dihydro-1,2,4-triazin- 5(2H)-one)
Authors: Tabatabaee Maasoomeh , Ghassemzadeh Mitra , Zarabi Behnaz , Neumüllerc Bernhard
Published: February 2015

Reaction of 4-amino-6-methyl-3-thio-3,4-dihydro-1,2,4-triazin-5(2H)-one (1) with 2-methoxybenzaldehyde, 4-methoxybenzaldehyde, 2-pyridinecarbaldehyde, and 2,4-dichlorobenzaldehyde under classical heating and microwave irradiation in a solventfree system led to the corresponding imines (Schiff bases) 2-5. All synthesized compounds have been characterized by IR and NMR spectroscopy, mass spectrometry and by X-ray diffraction studies.
Amanicadol, a Pimarane-type Diterpene from Phlomis amanica Vierch.
Authors: Yalçın Funda N. , Ersöz Tayfun , Bedir Erdal , Dönmez Ali A. , Stavri Michael , Zloh Mire , Gibbons Simon , Çaliş İhsan
Published: February 2015

Fractionation of the methanol extract of Phlomis amanica resulted in the isolation of a new pimarane type diterpene, amanicadol (1), together with the known glycosides lamiide, verbascoside (= acteoside), syringaresinol-4-O-β -glucoside, liriodendrin, syringin, and a caffeic acid ester, chlorogenic acid. The structure of the new compound was established on the basis of extensive 1D and 2D NMR spectroscopic data interpretation. Molecular modeling studies on 1 were conducted and showed that it exhibited low conformational flexibility. Additionally, NMR chemical shifts were calculated for 1 in vacuo, and calculated values were in very close agreement with those found experimentally.
Further Guaianolides from Amphoricarpos neumayeri ssp. murbeckii from Montenegro
Authors: Djordjević Iris , Jadranin Milka , Vajs Vlatka , Menković Nebojša , Tešević Vele , Macura Slobodan , Milosavljević Slobodan
Published: February 2015

The aerial parts of Amphoricarpos neumayeri ssp. murbeckii afforded eleven guaianolides with the same relative (1αH,4β H,5αH,7αH) configuration of the basic skeleton. All of them contained a CH2OX (X = H, acetyl or isovaleroyl) group in 4α-position, typical for amphoricarpolides. Four compounds (1 - 4) were isolated before from the same species, originating from different localities. Guaianolides 5 - 11 are new compounds. Compounds 7 and 8 were epoxidized at the 10α(14)-position. Instead of the Δ11(13)-double bond, observed in all previously isolated guaianolides from the same species, the four lactones contained 11α,13-diol (8 - 10) or 11α-OH,13-chloro (11) moieties respectively.
An Anhydrous High-pressure Synthesis Route to Rutile Type RhO2
Authors: Demazeau Gérard , Baranov Alexis , Pöttgen Rainer , Kienle Lorenz , Möller Manfred H. , Hoffmann Rolf-Dieter , Valldor Martin
Published: February 2015

A new anhydrous high-pressure synthesis route was developed for rutile type RhO2. Rhodium(III) chloride was reacted with Na2O2 at 600 °C under an oxygen pressure of 200 MPa yielding RhO2 and NaCl. X-ray powder diffractometer data and TEM observations confirmed the rutile structure: P42/mnm, a = 448.7(1), c = 308.9(1) pm, x(O) = 0.3125(8), leading to Rh-O distances of 195.0 (4x) and 198.3 pm (2x) in the slightly elongated octahedra. Structural transformations associated with the production of oxygen vacancies can be initiated by electron-beam heating.
Moderate-pressure Synthesis and Neutron Diffraction Study of New Metastable Oxides
Authors: Alonso Jose Antonio , Sánchez-Benítez Javier , Falcón Horacio , Martínez-Lope Maria Jesus , Muñoz Angel
Published: February 2015

We have synthesized two new series of metastable oxides, namely REMn2O5 and RECu3Mn4O12 (RE = rare earths) under moderate pressure conditions. A novel series of ferrimagnetic oxides has been obtained by replacing Mn3+ by Fe3+ in the parent REMn2O5 compounds (RE = Y, Dy, Ho, Er, Tm, Yb). The crystal structure has been studied by neutron powder diffraction (NPD); it contains chains of edge-linked Mn4+O6 octahedra connected via dimeric groups of Fe3+O5 square pyramids. The magnetic susceptibility and the thermal evolution of the NPD patterns reveal the onset of a ferrimagnetic structure below TC ≈ 165 K, characterized by the propagation vector k = 0. Immediately below TC, the Fe3+ and Mn4+ moments lie in an antiparallel arrangement along the c-axis direction. At lower temperatures, the magnetic moment of the rare-earth cations also participates in the magnetic structure, adopting a parallel arrangement with the Fe3+ spins. Some new derivatives of CaCu3Mn4O12 have been prepared at moderate pressures of 2 GPa by replacing Ca2+ by RE3+ cations in the series RECu3Mn4O12 (RE = Pr, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb); the concomitant electronic injection leads to a substantial contribution to TC. The crystal structures of the new materials were refined in the space group Im3̅ from NPD data for the non-absorbing RE cations. The unit cell parameters are considerably expanded with respect to CaCu3Mn4O12, as a result of the electronic injection. The r. t. magnetic structure displays a ferrimagnetic coupling between Mn3+/4+ and Cu2+ spins; at low temperatures there is an antiferromagnetic coupling of the RE3+ moments with the Mn substructure, which substantially reduces the susceptibility and the saturation magnetization.
High-pressure / High-temperature Synthesis of Transition Metal Oxide Perovskites
Authors: Rodgers Jennifer A. , Williams Anthony J. , Attfield J. Paul
Published: February 2015

Perovskite and related Ruddlesden-Popper type transition metal oxides synthesised at high pressures and temperatures during the last decade are reviewed. More than 60 such new materials have been reported since 1995. Important developments have included perovskites with complex cation orderings on A and B sites, multiferroic bismuth-based perovskites, and new manganites showing colossal magnetoresistance (CMR) and charge ordering properties.
Synthesis of Superhard and Ultrahard Materials by 3D-polymerization of C60, C70 Fullerenes Under High Pressure (15 GPa) and Temperatures up to 1820 K
Authors: Blank Vladimir D. , Buga Sergei G. , Dubitsky Gennadi A. , Serebryanaya Nadejda R. , Prokhorov Vyatcheslav M. , Mavrin Boris N. , Denisov Victor N. , Chernozatonskii Leonid A. , Berezina Sofia , Levin Vadim M.
Published: February 2015

Solid fullerenes C60 and C70 have been treated at high pressure of 15 GPa and high temperatures of 520 - 1820 K for a time of exposure of 60 s and a quenching rate of 300 K s−1 using a toroid-type apparatus. X-ray diffraction and Raman spectra confirm the realization of 3D-polymerized phases in these solids at 15 GPa. The pressure/temperature maps of synthesis of metastable carbon phases on the basis of C60 and C70 have thus been extended to 15 GPa. The longitudinal and shear sound wave velocities were measured by acoustic microscopy techniques. A maximum sound wave velocity of (21±1)×105 m s−1 was observed in the sample synthesized from C60 at T = 1170 K. The elastic constants were calculated using experimental data. The acoustic microscopy images of experimental samples have been investigated.
Synthesis of Pt Nanoparticles and Nanorods by Microwave-assisted Solvothermal Technique
Authors: Li Dongsheng , Komarneni Sridhar
Published: February 2015

Platinum nanoparticles and nanorods were synthesized by microwave-assisted solvothermal techniques. Changing the reaction conditions controlled particle size and morphology. The effects of the reaction conditions, such as the molar ratio of the polyvinylpyrrolidone (PVP) repeating unit to the metal sources, the concentration of metal sources, the reaction temperature, and the presence of distilled water were investigated. Nanoparticles of Pt were approximately 3 nm in size. Produced nanoparticles and nanorods were characterized by transmission electron microscopy. Image JTM software was used to calculate the particle size and size distribution.
Münzmetall-Lanthanid-Chalkogenide: II. Kupfer(I)-Lanthanid(III)- Sulfide der Zusammensetzung CuMS2 (M = Dy – Lu) im orthorhombischen B-Typ / Coinage Metal Lanthanide Chalcogenides: II. Copper(I) Lanthanide(III) Sulfides of the Composition CuMS2 (M = Dy – Lu) with the Orthorhombic B-Type Structure
Authors: Strobel Sabine , Schleid Thomas
Published: February 2015

Single crystals of the ternary copper(I) lanthanide(III) sulfides with the composition CuMS2 (M = Dy - Lu) are formed within seven days at 750 °C by oxidation of elemental copper and lanthanide metal with sulfur (molar ratio: 1 : 1 : 2, evacuated silica tubes) in equimolar quantities of CsCl, CsBr or CsI as fluxing agents. The CuYS2-type crystal structures (orthorhombic, Pnma, Z = 4; e. g. CuDyS2: a = 1342.51(9), b = 397.96(3), c = 627.43(5) pm and CuLuS2: a = 1315.06(9), b = 391.04(3), c = 624.18(5) pm) exhibit chains of cis edge-linked [CuS4]7− tetrahedra with the composition 1
∞{[Cu(S1)3/3(S2)1/1]3−} which run parallel to [010] and show hexagonal rod packing. Charge compensation and three-dimensional interconnection of these anionic strands occur via octahedrally coordinated M3+ cations surrounded by six S2− anions. These [MS6]9− octahedra share vertices and edges to form a three-dimensional network 3
∞{[M(S1)3/3(S2)3/3]−} with the ramsdellite-type topology of γ-MnO2. The metal sulfur distances within the [MS6] polyhedra are very similar (M-S: 263 - 279 pm), whereas those within the [CuS4] units cover the ranges 227 - 230 (Cu-S2) and 231 - 233 (Cu-S1) as well as 250 - 252 pm (Cu-S1′, 2×). The present work is the first comprehensive X-ray single crystal diffraction study of the complete isotypic B-type series CuMS2 (M = Dy - Lu).
2,5-Diformylbenzene-1,4-diol: A Versatile Building Block for the Synthesis of Ditopic Redox-Active Schiff Base Ligands
Authors: Kretz Tonia , Bats Jan Willem , Lerner Hans-Wolfram , Wagner Matthias
Published: February 2015

2,5-Diformylbenzene-1,4-diol (5) is a well-suited starting compound for the preparation of ditopic hydroquinone-based ligands. Here, we report an optimized synthesis of 5 which improves the overall yield from published 7% to 42 %. Three new ditopic Schiff base ligands, 2,5-[iPr2N(CH2)2N=CH]2 - 1,4-(OH)2-C6H2 (8), 2,5-(pyCH2N=CH)2-1,4-(OH)2-C6H2 (9), and 2,5-[py(CH2)2N=CH]2-1,4- (OH)2-C6H2 (10), have been synthesized from 5 and structurally characterized by X-ray crystal structure analysis (py = 2-pyridyl).
Asymmetric Synthesis of (+)-Hinokinin, (+)-Dihydrocubebin and Cubebin Dimethyl Ether, a New Lignan from Phyllanthus niruri
Authors: Enders Dieter , Milovanović Mile
Published: February 2015

The asymmetric synthesis of the new lignan cubebin dimethyl ether was accomplished in eight steps with an overall yield of 40 %. In addition, the known lignans (+)-hinokinin and (+)-dihydrocubebin were synthesized by this route. Our approach involves the highly diastereoselective and enantioselective (de ≥ 98%, ee ≥ 98%) construction of a trans-substituted 2,3- dibenzylbutyrolactone through an asymmetric Michael addition of an enantiopure lithiated aminonitrile to 5H-furan-2-one.
Two New Hydroxy Chalcone Derivatives from Thymus cilicicus
Authors: Ahmed Bahar , Al-Howiriny Tawfeq A.
Published: February 2015

The aerial part of Thymus cilicicus Linn. (Labiatae) has afforded two new hydroxy chalcone derivatives, characterized as 4, 2′, 4′, 6′, 7, 8-hexahydroxy-7 (8)-dihydro-chalcone (1), and 3, 4, 2′, 4′, 6′, 7, 8-heptahydroxy-7 (8)-dihydro-chalcone (2). The structures of the isolated compounds have been elucidated based on various spectral studies.