bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comprehensive metabolic profiling of mono‐ and polyglutamated folates and their precursors in plant and animal tissue using liquid chromatography/negative ion electrospray ionisation tandem mass spectrometry
Authors: Garratt Lee C. , Ortori Catharine A. , Tucker Gregory A. , Sablitzky Fred , Bennett Malcolm J. , Barrett David A. 
Published: July 2005

AbstractThis work reports the use of reversed‐phase ion‐pair chromatography coupled to electrospray ionisation mass spectrometry for the simultaneous profiling of folate‐based metabolites including natural folates, their polyglutamatyl derivatives and their biosynthetic precursors in plant and animal tissue. A simple sample preparation method, using 0.1% citric acid and ascorbic acid in ice‐cold methanol, was used to extract and stabilise the folates, and three internal standards were used. Chromatography was on a C18 column using slow gradient elution with a mobile phase consisting of methanol/water with 5 mM dimethylhexylamine. Mass spectrometric detection was performed by multiple reaction monitoring in seven separate time windows in negative ion mode over the 25 min run time. Full, quantitative analysis was obtained for 16 folates and a ‘semi‐quantitative’ analysis was possible for all other folates with up to eight conjugated glutamate residues by reference to structurally related calibration standards. The precision, accuracy and recovery of the method were generally within the accepted guidelines for a quantitative bioanalytical method and the method was linear over the range 0.2 to 10 ng of individual folate per sample. The method was applied to profile mono‐ and polyglutamated tetrahydrofolates (including subcellular analysis) in a range of plant species, including Arabidopsis, spinach, Brassica and wheat; the technique was also successfully applied to the profiling of folates in mouse tissue. Copyright © 2005 John Wiley & Sons, Ltd.
Perceived stress, health status, and the activity of neutrophils in undergraduates over one academic year
Authors: Ellard D.R. , Barlow J.H. , Mian R. 
Published: July 2005

AbstractTwenty‐eight undergraduates participated in a 12‐month (one academic year) study and were tested on six occasions to examine the effects of perceived stress on the activity of neutrophils. The six testing periods were selected to encompass variation in academic typical experiences over 1 year. At each time point, participants gave a small finger‐stick sample of blood before completing standard measure of perceived stress and health. Activity of neutrophils was determined from the whole bloods' capacity to reduce nitro‐blue tetrazolium (NBT) and was presented as percentage of NBT positive cells. Results showed that there were significant correlations between perceived stress levels and NBT positive cells (p < 0.05) at all six testing periods, with surprisingly large effects size. Further analysis (Fisher's Z averaging analysis) revealed the robust nature of this association. In addition, there were significant correlations between NBT positive cells and participants' current state of health on three of the six occasions: generally, as perceived stress increased the percentage of NBT positive neutrophils increased and health status decreased. The results support the hypothesis that stress may affect the activity of neutrophils, which in turn may influence health. Copyright © 2005 John Wiley & Sons, Ltd.
Changes in in vivo [3H]‐Ro15‐4513 binding induced by forced swimming in mice
Authors: Amitani Misato , Umetani Yukiko , Hosoi Rie , Kobayashi Kaoru , Abe Kohji , Inoue Osamu 
Published: July 2005

AbstractMice were forced to swim for 5 min in water at a temperature of 12°C (cold water swim stress) or 32°C (warm water swim stress), and stress‐induced analgesia (SIA) was measured using the tail‐flick test. The cold water swim stress induced non‐opioid SIA as well as hypothermia, whereas the warm water swim stress caused opioid SIA. The in vivo binding of [3H]‐Ro15‐4513 was measured in the stressed mice and compared with that in control mice. The specific binding of [3H]‐Ro15‐4513 in the cerebral cortex, hippocampus, and cerebellum was significantly altered by forced swimming in cold water. Apparent association and dissociation rate of [3H]‐Ro15‐4513 binding were decreased, and the change in the dissociation rate was most pronounced in the hippocampus. In contrast, no significant alterations were observed in in vitro binding. The hypothermia induced by the cold water swim stress seems to be the main reason for alterations in the specific binding of [3H]‐Ro15‐4513. The kinetics of a saturable amount of [3H]‐Ro15‐4513 in the blood and brain were also measured. The relative ratio of the radioactivity concentration in the brain to that in the blood was significantly decreased by forced swimming in cold water, indicating that the cold water swim stress induced changes in the nonspecific binding of [3H]‐Ro15‐4513 in the brain. These results together with previous reports suggested that non‐opioid SIA induced by the cold water swim stress might be related to alterations in the rates of general ligand–receptor interactions including GABAA/benzodiazepine system. Changes in the nonspecific binding might be also involved in non‐opioid SIA. Synapse 58:22–28, 2005. © 2005 Wiley‐Liss, Inc.
Possible role of mitochondria in posttetanic potentiation of GABAergic synaptic transmission in rat neocortical cell cultures
Authors: Storozhuk Maksim V. , Ivanova Svetlana Y. , Balaban Pavel M. , Kostyuk Platon G. 
Published: July 2005

AbstractIt has been previously demonstrated that mitochondria are of crucial importance for posttetanic potentiation (PTP) at neuromuscular junction. The aim of our study was to examine whether this may also be the case at a central synapse. To address this question, we studied possible mitochondrial involvement in PTP of GABAergic synaptic transmission in rat neocortical cultures, a preparation in which PTP has not been previously documented. Synaptic responses were evoked by local extracellular stimulation. Whole‐cell patch‐clamp technique was employed to record inhibitory postsynaptic currents (IPSCs) from postsynaptic neurons. Tetanic stimulation (30 Hz, 4 s) of the presynaptic neuron evoked an increase of IPSC amplitude, lasting for about 1 min. PTP was accompanied by a decrease of coefficient of variation of the IPSC and a decrease of paired‐pulse (IPSC2/IPSC1) ratio, indicating involvement of presynaptic mechanism(s) in PTP. Possible role of mitochondria in PTP was addressed using drugs affecting Ca2+ uptake and subsequent Ca2+ efflux: carbonyl cyanide 3‐chlorophenylhydrazone (CCCP) and tetraphenylphosphonium ions (TPP+). It was found that both CCCP (1–2 μM) and TPP+ (10 μM) either substantially decreased or eliminated PTP. These results further confirm presynaptic origin of PTP in neocortical neurons and suggest an important role of mitochondrial Ca2+ turnover in this form of synaptic plasticity at the central synapse. Synapse 58:45–52, 2005. © 2005 Wiley‐Liss, Inc.
One‐Dimensional Holodirected Lead(II) Coordination Polymer, [Pb(μ2‐TPPZ)(NO3)(ClO4)]n (TPPZ = 2, 3, 5, 6–tetra(2‐pyridyl)pyrazine)
Authors: Morsali Ali , Ramazani Ali 
Published: July 2005

AbstractA lead(II) complex with 2,3,5,6‐tetra(2‐pyridyl)pyrazine (TPPZ), nitrate, and perchlorate ligands has been synthesized and characterized by CHN elemental analysis and IR and 207Pb NMR spectroscopy. The single crystal X‐ray data of the [Pb2(μ‐TPPZ)2(NO3)2(ClO4)2] compound show that the complex is a one‐dimensional coordination polymer and that the Lead atom has a less‐common, ten‐coordinate holodirected geometry.
Novel Barium Beryllates Ba[Be2N2] and Ba3[Be5O8]: Syntheses, Crystal Structures and Bonding Properties
Authors: Leoni Stefano , Niewa Rainer , Akselrud Lev , Prots Yurii , Schnelle Walter , Göksuc Tahsin , Cetinkol Mehmet , Somer Mehmet , Kniep Rüdiger 
Published: July 2005

AbstractBa[Be2N2] was prepared as a yellow‐green microcrystalline powder by reaction of Ba2N with Be3N2 under nitrogen atmosphere. The crystal structure Rietfeld refinements (space group I4/mcm, a = 566.46(5) pm, c = 839.42(9) pm, Rint = 4.73 %, Rprof = 9.16 %) reveal the compound to crystallize as an isotype of the nitridoberyllates A[Be2N2] (A = Ca, Sr) consisting of planar 4.82 nets $^{2}_{\infty}\rm [(Be_{2}N_{2})^{2-}]$ of mutually trigonal planar coordinated Be and N species. Averaged magnetic susceptibility values for the anion [(Be2N2)2−] determined from measurements on A[Be2N2] with A = Mg, Ca, Ba allow to derive a diamagnetic increment for N3− χdia = (−13±1stat.) · 10−6emu mol−1.Colorless Ba3[Be5O8] was first obtained as an oxidation product of Ba[Be2N2] in air. The crystal structure was solved and refined from single crystal X‐ray diffaction data (space group Pnma, a = 942.9(1) pm, b = 1163.47(7) pm, c = 742.1(1) pm, R1 = 2.99 %, wR2 = 7.15 %) and contains infinite rods of Be in trigonal planar, tetrahedral and 3 + 1 coordination by O. The crystal structure is discussed in context with other known oxoberyllates. Electronic structure calculations and electron localization function diagrams for both compounds support the classification as nitrido‐ and oxoberyllate, respectively.
Crystal Structure and Magnetic Exchange in the Single Chloride‐Bridged Copper(II) Chain Compound [CuCl2(TzHy)] [TzHy = (4,5‐dihydro‐1,3‐thiazol‐2‐yl)hydrazine]
Authors: Barros‐García F. J. , Bernalte‐García Alvaro , Higes‐Rolando F. J. , Luna‐Giles F. , Pizarro‐Galán A. M. , Viñuelas‐Zahínos E. 
Published: July 2005

AbstractThe copper complex [CuCl2(TzHy)] has been synthesized and its crystal structure determined. The coordination complex contains polymeric [CuCl2(TzHy)]n chains in which the units are linked by μ‐chloro bridges. The chains run along the crystallographic c axis. The geometry around the copper(II) is best described as distorted square pyramidal. The equatorial positions are occupied by Cl(1) and Cl(2) ligands and one thiazolinic nitrogen atom and another hydrazinic nitrogen atom, from TzHy ligand. The axial position is occupied by the Cl(2b) ligand. The magnetic susceptibility measurements in the temperature range 4 – 290 K show a weak antiferromagnetic intrachain interactions (J = −8.6 cm−1).
Synthesis and Characterization of 1,3,2‐Bis (arylamino) phospholidine, 2‐oxide Derivatives: Crystal Structures of $\rm Cl(O)\overline{PN(p-Me-C_{6}H_{4})CH_{2}CH_{2}N}(p-Me-C_{6}H_{4})$ and $\rm ((CH_{2}C_{6}H_{5})(O)\overline{PN(p-Me-C_{6}H_{4})CH_{2}CH_{2}N}(p-Me-C_{6}H_{4})$
Authors: Gholivand Khodayar , Mojahed Fresia 
Published: July 2005

AbstractUsing phosphoryl chloride as a substrate, a family of 1,3,2‐bis(arylamino) phospholidine, 2‐oxide of the general formula $\rm (X)(O)\overline{PN(Ar)CH_{2}CH_{2}N}(Ar)$; (X=Cl, 6a; X=NMe2, 1b; X=N(CH2C6H5)(CH3), 2b; X=NHC(O)C6H5, 3b; X=4Me‐C6H4O, 4b; X=C6H5O, 5b; X=NHC6H11, 6b; X=OC4H8N, 7b; X=C5H10N, 8b; X=NH2, 9b; X=F, 10b and Ar=4Me‐C6H4) was prepared and characterized by 1H, 19F, 31P and 13C NMR and IR spectroscopy, and elemental analysis. A general and practical method for the synthesis of these compounds was selected. The structures of 6a and 2b were determined by single‐crystal X‐ray diffraction techniques. The low temperature NMR spectra of 2b revealed the restricted rotation of P‐N bond according to two independent molecules in crystalline lattice.
Methanolothermal Synthesis and Structures of the Quaternary Group 14 – Group 15 Cesium Selenidometalates Cs3AsGeSe5 and Cs4Ge2Se6
Authors: van Almsick Tobias , Sheldrick William S. 
Published: July 2005

AbstractCs3AsGeSe5 and Cs4Ge2Se6 can be prepared by methanolothermal reaction of elemental As, Ge and Se with Cs2CO3 at 190 °C. The former quaternary phase contains zweier $^{1}_{\infty}$[{AsGeSe5}3−] chains consisting of corner‐bridged GeSe4 tetrahedra and AsSe3 pyramids and represents the first GeIV‐AsIII chalcogenidometalate. Cs4Ge2Se6 exhibits discrete [Ge2Se6]4− anions formed by two edge‐sharing GeSe4 tetrahedra.
Darstellung und Kristallstrukturen von tBu‐substituierten Disiloxanen des Typus tBu2SiX‐O‐SiYtBu2 (X = Y = OH, Br; X = OH, Y = H) und den Addukten tBu3SiOH·(HO3SCF3)0.5·H2O und tBu3SiOLi·(LiO3SCF3)2·(H2O)2
Authors: Lerner H.‐W. , Scholz S. , Wiberg N. , Polborn K. , Bolte M. , Wagner M. 
Published: July 2005

AbstractSyntheses and Crystal Structures of tBu‐substituted Disiloxanes tBu2SiX‐O‐SiYtBu2 (X = Y = OH, Br; X = OH, Y = H) and of the Adducts tBu3SiOH·(HO3SCF3)0.5·H2O and tBu3SiOLi·(LiO3SCF3)2·(H2O)2The disiloxanes tBu2SiX‐O‐SiYtBu2 (X = Y = H, OH) are accessible from the reaction of CF3SO2Cl with tBu2SiHOH or tBu2Si(OH)2. By this reaction the disiloxane tBu2SiH‐O‐SiHtBu2 is formed together with tBu2SiH‐O‐SiOHtBu2. The disiloxanes tBu2SiX‐O‐SiYtBu2 (X = Y = Cl, Br) can be synthesized almost quantitatively from tBu2SiH‐O‐SiHtBu2 with Cl2 and Br2 in CH2Cl2. The structures of the disiloxanes tBu2SiX‐O‐SiYtBu2 (X = H, Y = OH; X = Y = OH, Br) show almost linear Si‐O‐Si units with short Si‐O bonds. Single crystals of the adducts tBu3SiOH·(HO3SCF3)0.5·H2O and tBu3SiOLi·(LiO3SCF3)2·(H2O)2 have been obtained from the reaction of tBu3SiOH with CF3SO3H and of tBu3SiO3SCF3 with LiOH. According to the result of the X‐ray structural analysis (hexagonal, P‐62c), tBu3SiOLi · (LiO3SCF3)2·(H2O)2 features the ion pair [(tBu3SiOLi)2(LiO3SCF3)3(H2O)3Li]+ [CF3SO3]−. The central framework of the cation forms a trigonal Li6 prism.
Synthesis, Characterization, and Crystal Structure of Thallium(I) Complex containing Monodeprotonated 2,6‐Pyridinedicarboxylic Acid
Authors: Rafizadeh Masoud , Amani Vahid , Neumüller Bernhard 
Published: July 2005

AbstractThe reaction of an ethanolic solution 2,6‐pyridinedicarboxylic acid (1, LH2) with TlNO3 in the presence of triethylamine led to the coordination polymer [Tl(LH)]n (2). The complex was characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. Crystal data for 2 at –80 °C: monoclinic, space group I2/a, a = 696.1(1), b = 1190.6(2), c = 931.0(2) pm, β = 103.28(1)°, Z = 4, R1 = 0.0256.
Synthesis, Characterization and Crystal Structures of new 1,2,4‐Triazole based Schiff‐bases and their Copper(I) Complexes
Authors: Ghassemzadeh Mitra , Tabatabaee Masoomeh , Soleimani Samaneh , Neumüller Bernhard 
Published: July 2005

AbstractThe reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, 1) with 4‐methoxy benzaldehyde and 3‐methoxybenzaldehyde in methanol led to the iminic derivatives 4‐(4‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)thione (2, L1) and 4‐(3‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (3, L2). The reaction of the latter with [(PPh3)2CuCl] in methanol solution gave the first CuI complex of 3, [(PPh3)2CuCl(L2)] (4) and in chloroform solution the complex [(PPh3)2CuCl(L2)]·2CHCl3 (5). All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for 2 at −80 °C: space group P21/c with a = 1351.3(3), b = 399.4(1), c = 2225.2(5) pm, β = 96.50(2)°, Z = 4, R1 = 0.0667, for 3 at −80 °C: space group R3c with a = b = 3020.4(2), c = 708.2(1) pm, Z = 18, R1 = 0.0435, for 4 at −80 °C: space group P21/c with a = 1427.8(1), b = 1129.0(1), c = 2622.8(2) pm, β = 97.19(1)°, Z = 4, R1 = 0.0517 and for 5 at −80 °C: space group ${\rm P}{\bar 1}$ with a = 1280.5(1), b = 1316.1(1), c = 1731.4(1) pm, α = 78.14(1)°, β = 86.06(1)°, γ = 64.69(1)°, Z = 2, R1 = 0.0525.
Über die Schichtstruktur von Cu2(H2O)4[C4H4N2][C6H2(COO)4]·2H2O
Authors: Köferstein Roberto , Robl Christian 
Published: July 2005

AbstractThe Layered Structure of Cu2(H2O)4[C4H4N2][C6H2(COO)4]·2H2OTriclinic single crystals of Cu2(H2O)4[C4H4N2][C6H2(COO)4]·2H2O have been grown in an aqueous silica gel. Space group ${\rm P}{\bar 1}$ (Nr. 2), a = 723.94(7) pm, b = 813.38(14) pm, c = 931.0(2) pm, α = 74.24(2)°, β = 79.24(2)°, γ = 65.451(10)°, V = 0.47819(14) nm3, Z = 1. Cu2+ is coordinated in a distorted, octahedral manner by two water molecules, three oxygen atoms of the pyromellitate anions and one nitrogen atom of pyrazine (Cu—O 194.1(2)–229.3(3) pm; Cu–N 202.0(2) pm). The connection of Cu2+ and [C6H2(COO)4)]4− yields infinite strands, which are linked by pyrazine molecules to form a two‐dimensional coordination polymer. Thermogravimetric analysis in air showed that the dehydrated compound was stable between 175 and 248 °C. Further heating yielded CuO.
Chemischer Transport ternärer Indiummolybdate
Authors: Steiner Udo , Reichelt Werner 
Published: July 2005

AbstractChemical Vapor Transport of Ternary Indium MolybdatesAn isothermal section of the phase diagram of the system In/Mo/O at 1273 K was established by isothermal equilibration and XRD analyses of quenched samples. The chemical vapor transport of In2Mo3O12 was investigated in dependence on mean transport temperature (823 K to 1123 K) and amount of transport agent (Cl2 or Br2). The observed transport behaviour is compared with results of thermodynamical calculations and the influence of mean temperature, transport agent and moisture contents is described in detail. Single crystals of the metal rich compound InMo4O6 were grown by chemical vapor transport in a temperature gradient 1273 K to 1173 K using H2O as transport agent. The gaseous compound In2MoO4(g) accounts for the chemical vapor transport of molybdenium compounds in the metal rich part of the ternary phase diagram In/Mo/O.
The First Titanium Molybdenum Antimonide: Ti5.42Mo2.58Sb9, a Substitution Variant of Zr2V6Sb9
Authors: Assoud Abdeljalil , Kleinke Katja M. , Kleinke Holger 
Published: July 2005

AbstractThe new ternary antimonide Ti5.42(2)Mo2.58Sb9 was uncovered by a reaction of the elements under exclusion of air at 1150 °C. It crystallizes in a ternary substitution variant of the V7.5Sb9 type, a structure not known to exist in either the Ti/Sb or the Mo/Sb system. The crystal structure of Ti5.42Mo2.58Sb9 was determined from single crystal X‐ray data: space group P4/nmm, with a = 9.8178(8) Å, c = 7.1857(8) Å, V = 692.6(1) Å3, Z = 2, R1 = 0.025, wR2 = 0.052 (all data). The structure contains four metal atom sites, two thereof occupied solely by Ti atoms, and two by different Ti/Mo mixtures. The former two correspond to the Zr sites, and the latter two to the V sites of the isostructural antimonide Zr2V6Sb9. The crystal structure is comprised of chains of face‐sharing TiSb8 square antiprisms, Ti/Mo tetrahedra and Sb atom pairs and squares. The electronic structure, computed with the LMTO approximation, is indicative of metallic properties. In addition to the dominating metal–Sb bonds, strong metal–metal and Sb–Sb bonds exist as well in Ti5.42Mo2.58Sb9. The Mo content per metal site increases with increasing metal–metal interactions.
Diorganomorpholinometallane von Gallium und Indium – Monomer‐Dimer‐Gleichgewichte in Lösung
Authors: Iravani Effat , Neumüller Bernhard 
Published: July 2005

AbstractDiorganomorpholinometalates of Gallium and Indium – Monomer‐Dimer‐Equilibrium in SolutionThe reaction of Li[N(CH2CH2)2O] (LiMorpholinate; Li(Morph)) with Me2GaCl and Me2InCl gives by salt‐elimination the diorganoamidometalates Me2M(Morph) ( M = Ga: 1; M = In: 2), respectively. 1 and 2 were characterized by NMR and vibrational spectroscopy as well as by X‐ray structure determinations. According to this, centrosymmetrical dimers are present in the solid state while a monomer‐dimer equilibrium was assumed for the THF‐solution. Cryoscopic molecular weight determinations confirmed our assumptions.
The Reactivity of Bis(para‐methoxyphenyl)telluroxide towards Triflic Acid and Diphenylphosphinic Acid. Theoretical Considerations of the Protonation and Hydration Process of Diorganotelluroxanes
Authors: Beckmann Jens , Dakternieks Dainis , Duthie Andrew , Lewcenko Naomi A. , Mitchell Cassandra , Schürmann Markus 
Published: July 2005

AbstractThe reaction of (p‐MeOC6H4)2TeO with two equivalents of HO3SCF3 and HO2PPh2 provided the tetraorganoditelluroxanes (F3CSO3)(p‐MeOC6H4)2TeOTe(p‐MeOC6H4)2(O3SCF3) (1) and (Ph2PO2)(p‐MeOC6H4)2TeOTe(p‐MeOC6H4)2(O2PPh2)·2 Ph2PO2H (2) in good yields. Compounds 1 and 2 were characterized by solution and solid‐state 31P and 125Te NMR spectroscopy, IR spectroscopy, electrospray mass spectrometry, conductivity measurements and single crystal X‐ray diffraction. In solution, compound 1 undergoes an electrolytic dissociation and reversibly reacts with traces of water to give the mononuclear cation [(p‐MeOC6H4)2TeOH]+ and triflate anions. Theoretical aspects of the protonation and hydration of model telluroxanes R2TeO (R = H, Me, Ph) were investigated by preliminary DFT calculations and compared to the corresponding selenoxanes R2SeO. The tellurium dihydroxides R2Te(OH)2 seem to be more stable than the hydrogen‐bonded complexes R2TeO·H2O.
Synthese, Kristallstruktur und Festkörper‐NMR‐spektroskopische Untersuchung des Oxonitridosilicates BaSi6N8O
Authors: Stadler Florian , Kraut Robert , Oeckler Oliver , Schmid Sabine , Schnick Wolfgang 
Published: July 2005

AbstractSynthesis, Crystal Structure and Solid‐State NMR Spectroscopic Investigation of the Oxonitridosilicate BaSi6N8OThe phase‐pure oxonitridosilicate BaSi6N8O has been synthesized starting from BaCO3 and silicon diimide Si(NH)2 in a radiofrequency furnace at temperatures below 1630 °C as a coarsely crystalline colorless material. The structure has been determined by single‐crystal X‐ray diffraction analysis (BaSi6N8O, space group Imm2 (no. 44), a = 810.5(2), b = 967.8(2), c = 483.7(1) pm, V = 379.4(2)·106 pm3, Z = 2, R1 = 0.014, 618 independent reflections, 44 parameters). The oxonitridosilicate comprises a three‐dimensional network structure of corner sharing SiN4 and SiON3 tetrahedra with Ba2+ located in the resulting voids. BaSi6N8O is isostructural with the oxonitridoalumosilicate (sialon) Sr2AlxSi12−xN16−xO2+x (x ≈ 2) that previously has been described in the literature. Furthermore, the anionic network of BaSi6N8O derives from that of the homeotypic reduced nitridosilicate SrSi6N8 by a topotactic insertion of oxygen into the Si–Si single bonds. In the 29Si MAS‐NMR spectrum two sharp isotropic signals have been observed at −54.0 and −56.3 ppm, respectively. With respect to their observed intensity ratio of 1 : 2.1(1) these two signals have to be attributed to the central atoms of SiON3 and SiN4 tetrahedra, respectively, which is in accordance with the X‐ray crystal structure determination (Si at Wyckoff positions 4d (SiON3) and 8e (SiN4)).
LiM2(NCN)Br3 (M = Sr, Eu): Synthesis and Crystal Structures of Solid‐State Carbodiimides with Empty Tetrahedral Metal Entities
Authors: Liao Wuping , Dronskowski Richard 
Published: July 2005

AbstractTwo solid‐state carbodiimide compounds, LiM2(NCN)Br3 (M = Sr, Eu), with characteristic empty tetrahedral M4 entities have been synthesized using a flux route, and their structures were determined by single‐crystal X‐ray diffraction. The new phases LiSr2(NCN)Br3 and LiEu2(NCN)Br3 are isotypical with the corresponding iodides and crystallize in the cubic system (($Fd{\bar 3}m$, Z = 16) but with smaller unit cells (a = 14.641(1) Å for LiSr2(NCN)Br3 and 14.572(1) Å for LiEu2(NCN)Br3). The extended structures comprise two interpenetrating three‐dimensional networks: the first one is built from isolated M4 tetrahedra capped by NCN2− anions on their triangular faces while the second is made from vertex‐sharing LiBr6 octahedra. The linear NCN2− anions exhibit the symmetrical carbodiimide shape and serve as linkers between the tetrahedral entities.
Formation and Crystal Structure of Stable Five‐coordinate Diorgano Cobalt(III) Complexes
Authors: Li Xiaoyan , Sun Hongjian , Klein Hans‐Friedrich , Flörke Ulrich 
Published: July 2005

AbstractThe mer‐octahedral complexes(2‐carbonyl)(4‐Me)(6‐tBu)phenolato[C,O]hydridotris(trimethylphosphine)cobalt(III) (1) or ‐(1‐carbonyl)(2‐oxo)(1,2‐diphenylethene)[C,O]hydridotris(trimethylphosphine)cobalt(III) (2) via formal insertion of propynoic acid ethyl ester into Co‐H functions afford pentacoordinate vinylcobalt(III) 3 and 4, respectively, that are diamagnetic and attain a square pyramidal structure as exemplified by an X‐ray diffraction analysis of 3.