bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of MEL genes in the genus Zygosaccharomyces
Authors: Turakainen Hilkka , Hankaanpää Marja , Korhola Matti , Aho Sirpa
Published: May 2005

We cloned and sequenced a Zygosaccharomyces cidri MEL gene with a view to investigating the structure and regulation of yeast MEL genes. The amino acid sequence deduced from the nucleotide sequence showed 78·6% and 78·2% similarity to Saccharomyces cerevisiae and Saccharomyces pastorianus α‐galactosidases, respectively. The expression of the MEL gene in several Zygosaccharomyces strains was induced by galactose.

An electrophoretic karyotype of several Zygosaccharomyces species was obtained using contour‐clamped electric field gel electrophoresis. The minimum number of chromosomes was five for Z. cidri, six for Z. fermentati, three for Z. florentinus, and four for Z. microellipsoides. The sizes of the chromosomes were generally larger than those of S. cerevisiae, the smallest containing approximately 0·4 megabase.

The MEL gene was located, using the Z. cidri MEL gene as a probe, on the largest chromosome of the Z. cidri strains. In addition, a smaller chromosome (600 kb) in Z. cidri strain CBS4575 showed hybridization to the homologous MEL probe. This chromosome was absent in Z. cidri strain CBS5666. The probe hybridized to the largest chromosome of Mel+ Z. fermentati strains but failed to hybridize to any chromosome of Mel+ Z. mrakii or Z. florentinus strains. These results suggest the existence of a polymorphic MEL gene family in the yeast Zygosaccharomyces.

The sequence has been deposited in the EMBL Data Library under Accession Number L24957.
Functional expression of human poly(ADP‐ribose) polymerase in Schizosaccharomyces pombe results in mitotic delay at G1, increased mutation rate, and sensitization to radiation
Authors: Avila Matías A. , Velasco Juan A. , Smulson Mark E. , Dritschilo Anatoly , Castro Rafael , Notario Vicente
Published: May 2005

The activity of poly(ADP‐ribose) polymerase (PADPRP), a chromatin‐associated enzyme present in most eukaryotic cells, is stimulated by DNA strand breaks, suggesting a role for the enzyme in the cellular response to DNA damage. However, the primary function of PADPRP remains unknown. We have selected Schizosaccharomyces pombe as a simple eukaryotic system in which to study PADPRP function because this fission yeast shares with mammalian cells important cellular features possibly associated with poly‐(ADP‐ribos)ylation pathways. We investigated the existence of an endogenous yeast PADPRP by DNA and RNA hybridization to mammalian probes under low‐stringency conditions and by PADPRP activity assays. Our data indicate that fission yeasts are naturally devoid of PADPRP. We therefore isolated S. pombe strains expressing PADPRP by transformation with a human full‐length PADPRP cDNA under the control of the SV40 early promoter. The human PADPRP construct was transcribed and translated in S. pombe, generating a major transcript of the same size (3.7 kb) as that detected in mammalian cells and a 113‐kDa polypeptide, identical in size to the native human PADPRP protein. Yeast recombinant PADPRP was enzymatically active and was recognized by antibodies to human PADPRP. S. pombe cells expressing PADPRP (SPT strains) showed a stable phenotype that was characterized by: (i) cell cycle retardation as a result of a specific delay at the G1 phase, (ii) decreased cell viability in stationary cultures, (iii) enhanced rates of spontaneous and radiation‐induced ade6‐ade7 mutations, and (iv) increased sensitivity to radiation. SPT strains may prove efficient tools with which to investigate PADPRP functions in eukaryotic cells.
Sequence analysis of the right end of chromosome XV in Saccharomyces cerevisiae: An insight into the structural and functional significance of sub‐telomeric repeat sequences
Authors: Pryde Fiona E. , Huckle Tonie C. , Louis Edward J.
Published: May 2005

Approximately 3·9 kb of DNA, centromere proximal to the previously sequenced Y′ element at the right end of chromosome XV in Saccharomyces cerevisiae strain YP1, has been sequenced. A number of the known sub‐telomeric repeat sequences were identified, including Y′, core X and STRs A, B. C and D. Several of these repeat elements contain potentially functional sequences. In addition, two other members of repeated gene families were identified. The first of these shows 61% and 60% DNA sequence identity to Enolases 1 and 2 respectively. The Enolase‐like sequence appears to be species specific, with three copies being found in all strains of S. cerevisiae studied. The location of the three copies is the same for all strains. The second repeated sequence has homology with known open reading frames on chromosomes III, V and XI. There are five or six copies of this sequence in all S. cerevisiae and S. paradoxus strains studied and three in S. bayanus strains. The analysis of this region and comparison to sub‐telomeric regions on other chromosomes gives some indication as to the potential functional and structural significance of sub‐telomeric repeat sequences. In addition, these findings are consistent with the idea that sub‐telomeric regions may be targets for unusual recombination events. The updated sequence has been deposited in the EMBL and GenBank databases under Accession Number M58718.
Genetic mapping of the α‐galactosidase MEL gene family on right and left telomeres of Saccharomyces cerevisiae
Authors: Naumov Gennadi I. , Naumova Elena S. , Louis Edward J.
Published: May 2005

The α‐galactosidase MEL2–MEL10 genes have been genetically mapped to right and left telomere regions of the following chromosomes of Saccharomyces cerevisiae: MEL2 at VII L, MEL3 at XVI L, MEL4 at XI L, MEL5 at IV L, MEL6 at XIII R, MEL7 at VI R, MEL8 at XV R, MEL9 at X R and MEL10 at XII R. A set of tester strains with URA3 inserted into individual telomeres and no MEL genes was used for mapping.
Localization of the dominant flocculation genes FLO5 and FLO8 of Saccharomyces cerevisiae
Authors: Teunissen Aloys W. R. H. , Van Den Berg Johan A. , Steensma H. Yde
Published: May 2005

In the yeast Saccharomyces cerevisiae three dominant flocculation genes, FLO1, FLO5 and FLO8 have been described. Until now only the FLO1 gene, which is located at chromosome I, has been cloned and sequenced. FLO5 and FLO8 were previously localized at chromosomes I and VIII respectively (Vezinhet, F., Blondin, B. and Barre, P. (1991). Mapping of the FLO5 gene of Saccharomyces cerevisiae by transfer of a chromosome during cytoduction. Biotechnol. Lett. 13, 47–52; Yamashita, I. and Fukui, S. (1983). Mating signals control expression of both starch fermentation genes and a novel flocculation gene FLO8 in the yeast Saccharomyces. Agric. Biol. Chem. 47, 2889–2896). This was not in agreement with our results. Here, we report the location of FLO5 and FLO8 on chromosomes VIII and I respectively.

By induced chromosome loss and genetic mapping, the FLO5 gene was localized at the right end of chromosome VIII approximately 34 cM centromere distal of PET3. This is part of the region that is present both at chromosome I and chromosome VIII. The location of FLO5 in this area of chromosome VIII made it necessary to re‐evaluate the localization of FLO8, which was previously thought to occur in this region. Both genetic and physical mapping showed that FLO8 is allelic to FLO1. Hence, there are only two known dominant flocculation genes, FLO1 and FLO5.

Analysis of the nucleotide sequence of chromosome VIII of a non‐flocculent strain revealed an open reading frame encoding a putative protein that is approximately 96% identical to the Flo1 protein.

This suggests that both dominant flocculation genes encode similar, cell wall‐associated, proteins with the same function in the flocculation mechanism.
Genetically‐modified brewing yeasts for the 21st century. Progress to date
Authors: Hammond John R. M.
Published: May 2005

Academic studies and traditional breeding of yeasts depend upon their sporulation lifestyle. The strains used have been specially selected to sporulate readily and to mate producing new yeast types. Unfortunately brewing yeast strains do not behave in this way. They sporulate poorly, any spores which are formed are usually non‐viable and any haploid strains produced are invariably non‐maters. Only in recent years, with the development of recombinant‐DNA techniques, has the specific breeding of new brewing yeast strains become widespread. Strains have been produced with the ability to ferment a wider range of carbohydrates, with altered flocculation properties and which produce beers with modified flavours. Many have been tested on the pilot scale and one, an amylolytic brewing yeast, has received approval for commercial use.
A Bicapped α‐Keggin Unit‐Supported Transition Metal Complex: Hydrothermal Synthesis and Characterization of [Cu(en)2(H2O)]2[Cu(en)2]0.5[Mo8V7O42{Cu(en)2}]
Authors: Zeng Qing‐Xin , Xu Ji‐Qing , Song Yu‐Jiang , Cui Xiao‐Bing , Shi Zhan
Published: May 2005

A new metal‐oxo cluster supported transition metal complex, [Cu(en)2(H2O)]2[Cu(en)2]0.5[MoVI8VIV6VVO42{Cu(en)2}], has been synthesized under hydrothermal conditions. Its structure was determined by single‐crystal X‐ray diffraction. The compound crystallizes in the triclinic system, space group $P{\bar 1}$ (No. 2), a = 12.245(5), b = 12.669(5), c = 20.949(8) Å, α = 77.120(13), β = 78.107(17), γ = 65.560(14)°, V = 2860(2) Å3, Z = 2. The metal‐oxo cluster contains a novel bicapped a‐Keggin structure unit and a [Cu(en)2]2+ unit covalently bonded to the [Mo8V7O42]7− cluster.
{[Zn2(Bim)3(OH)(H2O)]·(DMF)(H2O)3}∞: A Two Dimensional Coordination Polymer with Layer Silicate‐like Structure
Authors: Xu Hai‐Jun , Liu You‐Xun , Shen Zhen , Tian Yun‐Qi , You Xiao‐Zeng
Published: May 2005

A layer silicate‐like zinc(II) benzimidazolate polymer {[Zn2(Bim)3(OH)(H2O)]·(DMF)(H2O)3}∞ (1) was synthesized at room temperature and characterized with X‐ray single‐crystallography: Monoclinic, space group C2/m (No.12), a = 10.423(3) Å, b = 17.416(6) Å, c = 16.583(5) Å, β = 92.698(4), V = 3006.8(17) Å3.
Complexes of 1,3‐Bis(diphenylphosphano)propane (dppp) with Dichloroplatinum(II) and Bis(chlorogold(I)): Intramolecular versus Intermolecular AuI–AuI Association of [(μ‐dppp)(AuCl)2] in catena and cyclo Forms
Authors: Kaim Wolfgang , Dogan Akbey , Klein Axel , Záliš Stanislav
Published: May 2005

The compound [(μ‐dppp)(AuCl)2], previously reported to associate intermolecularly in a chain (catena) structure through AuI–AuI interactions (3.316Å), was obtained from gold(III) precursors in a cyclo form with shortened intramolecular AuI—AuI contacts at 3.237Å and a puckered AuPCCCPAu seven‐membered ring. DFT calculations using a large relativistic basis to account for the d10–d10 interaction reproduce the observed molecular structure in the crystal of this “linkage isomer”, including the conspicuous distortion at one of the gold atoms. The chelate complex [(dppp)PtCl2] was crystallized and structurally characterized as the dichloromethane solvate.
Crystal Structure of Octaethyloxyphthalocyaninato Copper, the Overlap Affect on the Ring Skeleton Distortion
Authors: Lin Mei‐Jin , Wang Jun‐Dong , Chen Nai‐Sheng
Published: May 2005

The crystal structure of 1,4,8,11,15,18,22,25‐octaethyloxyphthalocyaninatocopper was determined by X‐ray diffraction. The ring skeleton distortion is shown, which not only attributed to inter‐molecular steric congestion of substituents but also to the less overlap of the skeletons.
Synthesis, Crystal Structure and Luminescence of [Ag(PPh3)2(H2TMT)]
Authors: Wei Yong‐Qin , Wu Ke‐Chen , Zhuang Bo‐Tao , Zhou Zhang‐Feng , Zhang Ming‐Xin , Liu Cai‐Ping
Published: May 2005

The silver complex Ag(PPh3)2(H2TMT) (1)(H3TMT = 2,4,6‐trimercapto‐1,3,5‐triazine) has been synthesized and characterized. The ligand trimercaptotriazine exhibits a novel coordination mode and the complex shows a special hydrogen bonding linkage in the crystal packing. The colorless crystals of 1 exhibit broad emission in the visible region at room temperature. TDDFT calculation indicated that the π–π attraction is crucial for fluorescence of the title complex.
Kristallstruktur und Schwingungsspektrum von (H2NPPh3)2[SnCl6]·2CH3CN
Authors: Neumüller Bernhard , Weller Frank , Dehnicke Kurt
Published: May 2005

Crystal Structure and Vibrational Spectrum of (H2NPPh3)2[SnCl6]·2CH3CN

Single crystals of (H2NPPh3)2[SnCl6]·2CH3CN (1) were obtained by oxidative addition of tin(II) chloride with N‐chloro‐triphenylphosphanimine in acetonitrile in the presence of water. 1 is characterized by IR and Raman spectroscopy as well as by a single crystal structure determination: Space group ${\rm P}{\bar 1}$, Z = 2, lattice dimensions at 193 K: a = 1029.6(1), b = 1441.0(2), c = 1446.1(2) pm, α = 90.91(1)°, β = 92.21(1)°, γ = 92.98(1)°, R1 = 0.0332. 1 forms an ionic structure with two different site positions of the [SnCl6]2− ions. One of them is surrounded by four N‐hydrogen atoms of four (H2NPPh3)+ ions, four CH3CN molecules form N–H···N≡C–CH3 contacts with the other four N‐hydrogen atoms of the cations. Thus, 1 can be written as [(H2NPPh3)4(CH3CN)4(SnCl6)]2+[SnCl6]2−.
Synthese, Kristallstruktur und Eigenschaften von Chrom(III)‐trimetaphosphimat‐Heptahydrat, Cr(PO2NH)3·7H2O
Authors: Correll Sascha , Sedlmaier Stefan , Schnick Wolfgang
Published: May 2005

Synthesis, Crystal Structure, and Properties of Chromium(III) Trimetaphosphimate Heptahydrate, Cr(PO2NH)3·7H2O

Chromium(III) trimetaphosphimate heptahydrate, Cr(PO2NH)3·7H2O, was synthesized by combining equimolar aqueous solutions of Na3(PO2NH)3·4H2O and Cr(NO3)3·9H2O. Suitable single crystals for X‐ray crystal structure determination were obtained by the reaction of an aqueous solution of Na3(PO2NH)3·4H2O with Cr(NO3)3·9H2O (molar ratio 2 : 1) using gel crystallization in gelatine gels. The structure of Cr(PO2NH)3·7H2O was solved by single‐crystal X‐ray methods (P21/n; a = 946.1(2), b = 1076.0(2), c = 1295.4(3) pm, β = 92.68(3)°; Z = 4). The P3N3 rings of the trimetaphosphimate ions exhibit a composition of the boat and the twist conformation in the ratio 1 : 1. The conformation of the anions has been analysed using torsion angles, displacement asymmetry parameters, and puckering parameters. Cr3+ is coordinated nearly octahedrally by six crystal water molecules. The trimetaphosphimate ions do not take part in that coordination. In the crystal these complex ions are interconnected by N–H···O und O–H···O hydrogen bonds. Thus, a three‐dimensional network is formed. The arrangement of the [Cr(OH2)6]3+ octahedra and the (PO2NH)33− ions can be described as a distorted variant of the CsCl structure type.
Cycloadditions of Diarylgermylenes to a Diazabutadiene [1]
Authors: Arndt Annika , Schäfer Helmut , Saak Wolfgang , Weidenbruch Manfred
Published: May 2005

The reaction of tetrakis(2‐tert‐butyl‐4,5,6‐trimethylphenyl)digermene, which dissociates into the germylene molecules 2 in solution, with 1,4‐diisopropyl‐1,4‐diazabuta‐1,3‐diene (3) furnishes the [4+1] cycloaddition product of 2 to the nitrogen atoms of 3. Under drastic conditions tetrakis(2,4,6‐triisopropylphenyl)digermene also forms the germylene molecules 6 which react with 3 in a similar fashion to afford the corresponding [4+1] cycloadduct.
Thiosilicate der Selten‐Erd‐Elemente: III. KLa[SiS4] und RbLa[SiS4] – Ein struktureller Vergleich
Authors: Hartenbach Ingo , Schleid Thomas
Published: May 2005

Thiosilicates of the Rare‐Earth Elements: III. KLa[SiS4] and RbLa[SiS4] – A Structural Comparison

Pale yellow, platelet shaped, air‐ and water resistant single crystals of KLa[SiS4] derived from the reaction of lanthanum (La) and sulfur (S) with silicon disulfide (SiS2) in a molar ratio of 2 : 3 : 1 with an excess of potassium chloride (KCl) as flux and source of potassium ions in evacuated silica ampoules at 850 °C within seven days. The analogous reaction utilizing a melt of rubidium chloride (RbCl) instead also leads to yellow comparable single crystals of RbLa[SiS4]. The potassium lanthanum thiosilicate crystallizes monoclinically with the space group P21/m (a = 653.34(6), b = 657.23(6), c = 867.02(8) pm, β = 107.496(9)°) and two formula units per unit cell, while the rubidium lanthanum thiosilicate has to be assigned orthorhombically with the space group Pnma (a = 1728.4(2), b = 667.23(6), c = 652.89(6) pm) and four formula units in its unit cell. In both compounds the La3+ cations are surrounded by 8+1 sulfide anions in the shape of tricapped trigonal prisms. The Rb+ cations in RbLa[SiS4] show a coordination number of 9+2 relative to the S2− anions, which form pentacapped trigonal prisms about Rb+. This coordination number, however, is apparently too high for the K+ cations in KLa[SiS4], so that they only exhibit a bicapped trigonal prismatic environment built up by eight S2− anions. The isolated thiosilicate tetrahedra [SiS4]4− of the rubidium compound are surrounded by La3+ both edge‐ and face‐capping, but terminal as well as edge‐ and face‐spanning by Rb+. In the potassium compound there is no change for the La3+ environment about the [SiS4]4− tetrahedra, but the K+ cations are only able to attach terminal and via edges. The whole structure is built up by anionic {La[SiS4]}− layers that are separated by the alkali metal cations. In direct comparison the two thiosilicate structures can be regarded as stacking variants.
Syntheses and Structures of RE4Pt10In21 (RE = La–Nd)
Authors: Zaremba Vasyl I. , Hlukhyy Viktor , Rodewald Ute Ch. , Pöttgen Rainer
Published: May 2005

The isotypic indides RE4Pt10In21 (RE = La, Ce, Pr, Nd) were prepared by melting mixtures of the elements in an arc‐furnace under an argon atmosphere. Single crystals were synthesized in tantalum ampoules using special temperature modes. The four samples were studied by powder and single crystal X‐ray diffraction: Ho4Ni10Ga21 type, C2/m, a = 2305.8(2), b = 451.27(4), c = 1944.9(2) pm, β = 133.18(7)°, wR2 = 0.045, 2817 F2 values, 107 variables for La4Pt10In21, a = 2301.0(2), b = 448.76(4), c = 1941.6(2) pm, β = 133.050(8)°, wR2 = 0.056, 3099 F2 values, 107 variables for Ce4Pt10In21, a = 2297.4(2), b = 447.4(4), c = 1939.7(2) pm, β = 132.95(1)°, wR2 = 0.059, 3107 F2 values, 107 variables for Pr4Pt10In21, and a = 2294.7(4), b = 446.1(1), c = 1938.7(3) pm, β = 132.883(9)°, wR2 = 0.067, 2775 F2 values, 107 variables for Nd4Pt10In21. The 8j In2 positions of all structures have been refined with a split model. The In1 sites of the lanthanum and the cerium compound show small defects, leading to the refined composition La4Pt10In20.966(6) and Ce4Pt10In20.909(6) for the investigated crystals. The same position shows Pt/In mixing in the praseodymium and neodymium compound leading to the refined compositions Pr4Pt10.084(9)In20.916(9) and Nd4Pt10.050(9)In20.950(9). All platinum atoms have a tricapped trigonal prismatic coordination by rare‐earth metal and indium atoms. The shortest interatomic distances occur for Pt–In followed by In–In. Together, the platinum and indium atoms build up three‐dimensional [Pt10In21] networks in which the rare earth atoms fill distorted pentagonal tubes. The crystal chemistry of RE4Pt10In21 is discussed and compared with the RE4Pd10In21 indides and isotypic gallides.
1,4‐Di(isopropyl)‐1,4‐diazabutadien als Abfangreagenz für monomere Bruchstücke des Tetragalliumclusters Ga4[C(SiMe3)3]4 – Bildung eines ungesättigten GaN2C2‐Heterocyclus und eines Oxidationsprodukts mit Ga‐O‐O‐Ga‐Gruppe
Authors: Uhl Werner , Melle Sandra , Prött Malte
Published: May 2005

1,4‐Di(isopropyl)‐1,4‐diazabutadiene as a Reagent for the Trapping of Monomeric Fragments of the Tetragalliumcluster Ga4[C(SiMe3)3]4 – Formation of an Unsaturated GaN2C2 Heterocycle and an Oxidation Product Containing a Ga‐O‐O‐Ga Group

The tetrahedral tetragallium cluster Ga4[C(SiMe3)3]4 (1) dissociates upon dissolution to yield the monomeric fragments Ga‐R [R = C(SiMe3)3]. These monomers could be trapped now by the treatment of their solutions with 1,4‐di(isopropyl)‐1,4‐diazabutadiene. The product of the cycloaddition reaction (2) possesses a five‐membered GaN2C2 heterocycle with a coordinatively unsaturated gallium atom and an endocyclic C=C double bond. 2 is rather sensitive towards oxidation by traces of air. The contact with oxygen yielded a digallium peroxide [(C2N2iPr2)RGa‐O‐O‐GaR(C2N2iPr2)] (3) which was isolated in a very low yield only and which has a gallium atom attached to each oxygen atom of the inner peroxo group. Both chelating ligands of 3 possess an unpaired electron.
N‐Heterocyclic Phosphenium, Arsenium, and Stibenium Ions as Ligands in Transition Metal Complexes: A Comparative Experimental and Computational Study
Authors: Burck Sebastian , Daniels Jörg , Gans‐Eichler Timo , Gudat Dietrich , Nättinen Kalle , Nieger Martin
Published: May 2005

Reaction of 2‐chloro‐1,3,2‐diazaarsolenes and ‐diazaphospholenes with Tl[Co(CO)4] gives instable complexes of type [Co(ER2)(CO)4] which decarbonylated to yield [Co(ER2)(CO)3]. Spectroscopic and X‐ray diffraction studies revealed that the tetracarbonyl complexes can be formulated as ion pair for E = P and as covalent metalla‐arsine for E = As, and the tricarbonyl complexes as carbene‐like species with a formal E=Co double bond. A similar reactivity towards Tl[Co(CO)4] was also inferred for 1,3,2‐diazastibolenes although the products were not isolable and their constitution remained uncertain. Evaluation of structural and computational data suggests that the weak and polarized Co–As bond in [Co(AsR2)(CO)4] can be characterized as an “inverse” M→L donor‐acceptor bond. The computational studies disclosed further η2(EN)‐coordination of the EN2C2 heterocycle as an alternative to the formation of a carbene‐like structure for [Co(ER2)(CO)3]. The η2‐complex is less stable for E = P but close in energy for E = As and more stable than the carbene‐like complex for E = Sb.
Synthesis of Nanocrystalline Zr3N4 and Hf3N4 Powders from Metal Dialkylamides
Authors: Li Jinwang , Dzivenko Dmytro , Zerr Andreas , Fasel Claudia , Zhou Yanping , Riedel Ralf
Published: May 2005

A simple process to synthesize Zr3N4 and nitrogen‐rich Hf3N4 powders via ammonolysis of metal dialkylamides, i.e. Zr(NEt2)4 and Hf(NEt2)4, at temperatures below 700 °C is presented. The obtained nitrides have a rhombohedrally distorted NaCl‐type structure, which has previously been reported only for nitrogen‐rich films of these nitrides. Regardless of the atmosphere (N2 and He), the Zr3N4 starts to decompose above about ∼ 650 °C and achieves the highest decomposition rate at about 900 °C, finally yielding the mononitride ZrN. Both Zr3N4 and Hf3N4 powders are nanocrystalline with the crystal size of about 2 nm.
Organometallic Diaza‐dimetalla‐Norbornanes and ‐Cyclohexanes of Aluminium, Gallium and Indium
Authors: Tian Xin , Fröhlich Roland , Mitzel Norbert W.
Published: May 2005

Selective formation of 1,3,3,4,6,6‐hexamethyl‐1,4‐diaza‐3,6‐diinda‐norborane was achieved by the reaction of bis(lithiomethyl‐methylamino)methane with dimethylindium chloride by simultaneous formation of two dative metal‐carbon and two metal‐nitrogen bonds accompanied by two ring closures. The synthesis of heterometallic compounds of this type, namely 1,3,3,4,6,6‐hexamethyl‐3‐alumina‐1,4‐diaza‐6‐galla‐norborane [Me2AlCH2N(Me)]CH2[N(Me)CH2GaMe2], was also attempted by the reaction of bis(lithiomethyl‐methylamino)methane with dimethylaluminium and ‐gallium chloride. This compound is formed, but cannot be separated from the simultaneously formed homometallic compounds [Me2MCH2N(Me)]2CH2(M = Al, Ga). The compounds were identified by elemental analyses, mass spectra, NMR spectroscopy (1H, 13C), and by determination of their crystal structures in which they are present as monomers. The norbornane‐like structure is favoured over potential isomers containing three‐membered rings and over polymeric aggregation in both compounds. In addition, the crystal structure of dimethyl(dimethylaminomethyl)indium was determined by single crystal X‐ray diffraction, which shows an intermolecular aggregation into a six‐membered ring dimer.
Anionic Diversity in Iodobismuthate Chemistry
Authors: Lindsjö Martin , Fischer Andreas , Kloo Lars
Published: May 2005

Three salts containing different iodobismuthate anions have been synthesized. [(CH3)2NH2]3[BiI6] was prepared by oxidation of bismuth by iodine in N,N‐dimethylformamide. [(CH3)2NH2]3[BiI6] crystallizes in the space group ${\rm R}{\bar 3}$ with a = 30.760(3) Å and c = 8.8039(5) Å and contains monomeric [BiI6]3− anions. The hydrate Na4[Bi2I10] · 14H2O was prepared by the oxidation of bismuth using iodine in acetonitrile in the presence of NaI. Na4[Bi2I10] · 14H2O crystallizes in the space group C2/m with a = 12.875(2) Å, b = 16.177(2) Å, c = 9.904(2) Å and β = 106.57(6)°. The structure contains dimeric [Bi2I10]4− anions and rows of sodium ions, with bridging water molecules. The hydrate [Na{(CH3)2NCHO}2(H2O)]3[Bi2I9] was prepared by dissolution of Na4[Bi2I10] · 14H2O in N,N‐dimethylformamide and crystallizes in the space group ${\rm P}{\bar 1}$ with a = 13.2309(13) Å, b = 13.3791(14) Å, c = 18.722(2) Å, α = 70.338(9)°, β = 72.651(9)° and γ = 62.183(5). The structure contains dimeric [Bi2I9]3− anions and cationic polymers, [Na{(CH3)2NCHO}2(H2O)]+.
Halbantiperowskite: Zur Struktur der Shandite M3/2AS (M = Co, Ni; A = In, Sn) und ihren Typ‐Antitypbeziehungen
Authors: Weihrich Richard , Anusca Irina , Zabel Manfred
Published: May 2005

Half‐Antiperovskites: Structure and Type‐Antitype Relations of Shandites M3/2AS (M = Co, Ni; A = In, Sn)

The crystallographic and electronic structures of the ternary shandite type sulfides M3A2S2 (M = Co, Ni; A = In, Sn) were investigated by X‐ray diffraction, as well as density functional theory (DFT) band structure calculations with respect to superstructure and type‐antitype relations. The crystal structure of Ni3In2S2 (space group $R{\bar 3}{\rm m}$, a = 5.371Å, c = 13.563Å) was determined from a single crystal. The shandites show type‐antitype relations to oxostannates(II) M2Sn2O3 (M = K, Rb) analogously to perovskite and antiperovskite. With a perovskite superstructure a group‐subgroup relation is given to antiperowskites like Ni3MgC. Because of the ordered occupation of half of the M‐positions the title compounds are described as half‐antiperowskites M3/2AS. The occupation scheme causes the formation of Kagomé‐nets. From bond distances covalent Ni–S bonds (< 2.20Å), ionic Sn–S and In–S‐interactions, as well as metallic In–Ni and Sn–Ni are concluded. The electronic band structures of the shandites show metallic characteristics similar to Ni3MgC. A band filling scheme explains the stability and properties from Co3In2S2 to Ni3Sn2S2. The highest partly occupied bands are formed by a strong mixing of Co(Ni)‐3d, In(Sn)‐5p and S‐3p states. A bonding description [M3S2]n−[A2]n+ accounts for the structural and electronic properties. Band gaps for Ni3In2S2 and Co3Sn2S2 indicate metal– insulator and magnetic phase transitions.
Crystal Structure of the Mixed‐Valent Basic Mercury Nitrate HgI2(NO3)2·HgII(OH)(NO3)·HgII(NO3)2·4HgIIO [= Hg8O4(OH)(NO3)5]
Authors: Weil Matthias
Published: May 2005

Light‐yellow single crystals of the mixed‐valent mercury‐rich basic nitrate Hg8O4(OH)(NO3)5 were obtained as a by‐product at 85 °C from a melt consisting of stoichiometric amounts of (HgI2)(NO3)2·2H2O and HgII(OH)(NO3). The title compound, represented by the more detailed formula HgI2(NO3)2·HgII(OH)(NO3)·HgII(NO3)2·4HgIIO, exhibits a new structure type (monoclinic, C2/c, Z = 4, a = 6.7708(7), b = 11.6692(11), c = 24.492(2) Å, β = 96.851(2)°, 2920 structure factors, 178 parameters, R1[F2 > 2σ(F2)] = 0.0316) and is made up of almost linear [O‐HgII‐O] and [O‐HgI‐HgI‐O] building blocks with typical HgII‐O distances around 2.06Å and a HgI‐O distance of 2.13Å. The Hg22+ dumbbell exhibits a characteristic Hg‐Hg distance of 2.5079(7) Å. The different types of mercury‐oxygen units form a complex three‐dimensional network exhibiting large cavities which are occupied by the nitrate groups. The NO3− anions show only weak interactions between the nitrate oxygen atoms and the mercury atoms which are at distances > 2.6Å from one another. One of the three crystallographically independent nitrate groups is disordered.
Transition Metal Promoted Addition of Methanol to Cyanoguanidine. Molecular Structure and Properties of the Generated Copper(II) and Nickel(II) Complexes
Authors: Williams Patricia A. M. , Ferrer Evelina G. , Baeza Natalia , Piro Oscar E. , Castellano Eduardo E. , Baran Enrique J.
Published: May 2005

The reaction of the CuII and NiII complexes of saccharin with dicyandiamide (cyanoguanidine, cnge) in methanol produces the addition of methanol to the nitrile moiety of this molecule. Furthermore, the product of the reaction coordinates the metal centers generating two new complexes containing saccharinate as the counter anion. The crystal structures of [Cu(cnge‐OCH3)2](sac)2 and of [Ni(cnge‐OCH3)2](sac)2·2H2O (cnge‐OCH3 = 1‐amidino‐O‐methylurea) were solved by single crystal X‐ray diffractometry. Both complexes crystallize in the triclinic space group ${\rm P}{\bar 1}$ and the metallic cations present a quite similar centrosymmetric planar conformation. The complexes were characterized by means of electronic and infrared spectroscopy and also their magnetic and thermal behavior was investigated.
Zur Elektronenstruktur hochsymmetrischer Verbindungen der f‐Elemente. 38 [1] Kristall‐, Molekül‐ und Elektronenstruktur von Tris(hydrotris(1‐pyrazolyl)borato)‐samarium(III)
Authors: Reddmann Hauke , Apostolidis Christos , Walter Olaf , Rebizant Jean , Amberger Hanns‐Dieter
Published: May 2005

Electronic Structures of Highly Symmetrical Compounds of f Elements. 38 [1] Crystal, Molecular and Electronic Structure of Tris(hydrotris(1‐pyrazolyl)borato)samarium(III)

Tris(hydrotris(1‐pyrazolyl)borato)samarium(III) (SmTp3) crystallizes in the space group P63/m (No. 176) with two molecules in the unit cell. The Sm3+ central ion is coordinated by nine N atoms in the shape of a tricapped trigonal prism, leading to an effective crystal field (CF) of D3h symmetry. The underlying CF splitting pattern was extracted from the absorption and luminescence spectra run at room and low temperatures, and simulated by fitting the free parameters of a phenomenological Hamiltonian achieving an r.m.s. deviation of 9.4 cm−1 for 58 assignments. The parameters used allow the estimation of the global ligand field strength experienced by the Sm3+ central ion, the insertion of SmTp3 into empirical nephelauxetic and relativistic nephelauxetic series, and the set‐up of experimentally based nonrelativistic and relativistic molecular orbital schemes in the f range.
Synthesis of a Stable Biphenyl‐Bis(carbene) and ‐Bis(silylene) [M{(NCH2But)2C6H3‐3,4}]2 (M = C or Si)
Authors: Gehrhus Barbara , Hitchcock Peter B. , Lappert Michael F.
Published: May 2005

Treatment of the biphenyl derivative [S=C{(NCH2But)2C6H3‐3,4}]2 or [Cl2Si{(NCH2But)2C6H3‐3,4}]2 with C8K afforded the new bis(carbene) 1 or the first bis(silylene) 2, respectively. The X‐ray structure of 2 is presented.
Synthesis, Crystal Structure Determination from X‐Ray Powder Diffractometry and Vibrational Spectroscopic Properties of Mg[N(CN)2]2 · 4 H2O
Authors: Irran Elisabeth , Jürgens Barbara , Schmid Sabine , Schnick Wolfgang
Published: May 2005

Magnesium dicyanamide tetrahydrate Mg[N(CN)2]2 · 4 H2O was synthesized by aqueous ion exchange starting from Na[N(CN)2] and Mg(NO3)2 · 6 H2O. The crystal structure was solved and refined on the basis of powder X‐ray diffraction data (P21/c, Z = 2, a = 737.50(2), b = 732.17(1), c = 971.67(2) pm, β = 98.074(1)°, wRp = 0.059, Rp = 0.046, RF = 0.075). In the crystal there are neutral complexes [Mg[N(CN)2]2(H2O)4] which are only connected via hydrogen bonds. Above 40 °C the tetrahydrate decomposes into anhydrous Mg[N(CN)2]2.
Trichloropalladate(II) Complexes with Pyridine Ligands – Molecular Structure and Conformational Analysis of [K(18C6)][PdCl3(py)]
Authors: Konkol Marcin , Wagner Christoph , Schwieger Sebastian , Lindner Ronald , Steinborn Dirk
Published: May 2005

[K(18C6)]2[Pd2Cl6] (1) (18C6 = 18‐crown‐6) was found to react with pyridines in a strictly stoichiometric ratio 1 : 2 in methylene chloride or nitromethane to yield trichloropalladate(II) complexes [K(18C6)][PdCl3(py*)] (py* = py, 2a; 4‐Bnpy, 2b; 4‐tBupy, 2c; Bn = benzyl; tBu = tert‐butyl). The reaction of 1 with pyrimidine (pyrm) in a 1 : 1 ratio led to the formation of the pyrimidine‐bridged bis(trichloropalladate) complex [K(18C6)]2[(PdCl3)2(μ‐pyrm)] (3). The identities of the complexes were confirmed by means of NMR spectroscopy (1H, 13C) and microanalysis. The X‐ray structure analysis of 2a reveals square‐planar coordination of the Pd atom in the [PdCl3(py)]− anion. The pyridine plane forms with the complex plane an angle of 55.8(2)°. In the [K(18C6)]+ cation the K+ lies outside the mean plane of the crown ether (defined by the 6 O atoms) by 0.816(1) Å. There are tight K···Cl contacts between the cation and the anion (K···Cl1 3.340(2) Å, K···Cl2 3.166(2) Å). To gain an insight into the conformation of the [PdCl3(py)]− anion, DFT calculations were performed showing that the equilibrium structure (6eq) has an angle between the pyridine ligand and the complex plane of 35.3°. Rotation of the pyridine ligand around the Pd–N vector exhibited two transition states where the pyridine ligand lies either in the complex plane (6TSpla, 0.87 kcal/mol above 6eq) or is perpendicular to it (6TSper, 3.76 kcal/mol above 6eq). Based on an energy decomposition analysis the conformation of the anion is discussed in terms of repulsive steric interactions and of stabilizing σ and π orbital interactions between the PdCl3− moiety and the pyridine ligand.
Dinuclear and Mononuclear Platinum(II) and Palladium(II) Complexes with Modified 2,2′‐Dipyridylamine Ligands Featuring a Cisplatin Analogous Structure Motif
Authors: Fakih Sarah , Tung Wing Chau , Eierhoff Dirk , Mock Christian , Krebs Bernt
Published: May 2005

In modern cancer therapy the clinical application of platinum‐based drugs is more and more limited by the occurrence of intrinsic or acquired resistances. In this context the potential use of dinuclear platinum complexes in chemotherapy is increasingly relevant. The novel complexes Pd(Bzdpa)Cl2, Pd2(C4H8(dpa)2)Cl4, and Pt2(C4H8(dpa)2)Cl4 allow a direct comparison of mono‐ and dinuclear palladium and platinum complexes respectively deriving from a 2,2′‐dipyridylamine (Hdpa) ligand system. They were characterized by single crystal X‐ray analysis as well as infrared spectroscopy and elemental analysis. The cisplatin analogous mononuclear palladium complex Pd(Bzdpa)Cl2 (1) (Bzdpa: (2,2′‐dipyridylbenzyl)amine) belongs to a range of 2,2′‐dipyridylamine‐based compounds which were extensively studied in our laboratories. 1 crystallizes in the orthorhombic space group Pna21 with a = 13.722(3), b = 13.457(3), c = 9.483(2), V = 1751.1(6) Å3, and Z = 4. The metal binding motif of 1 was expanded by a flexible butyl‐linker to form the tetradentate C4H8(dpa)2 ligand. The resulting isotypic dinuclear complexes Pd2(C4H8(dpa)2)Cl4·2CH3CN (2) and Pt2(C4H8(dpa)2)Cl4·2CH3CN (3) crystallize in the triclinic space group $P{\bar 1}$ with a = 7.8427(2), b = 8.7940(2), c = 11.7645 (3), α = 79.219(2)°, β = 84.033(2)°, γ = 87.744(2)°, V = 792.58(3) Å3 (2) and a = 7.831(5), b = 8.814(5), c = 11.817(5), α = 79.271(5)°, β = 83.571(5)°, γ = 88.063(5)°, V = 796.3(8) Å3 (3), both with one centrosymmetrical molecule in the unit cell.
Plasmachemistry. Formation of Chlorosilazanes, Chlorogermazanes and Related Compounds
Authors: Schiefenhövel Nils , Himmel Hans‐Jörg , Binnewies Michael
Published: May 2005

The plasmachemically activated reaction between N2 and SiCl4 leads via nitrogen atoms to numerous chlorosilazanes: NSi3Cl9, N2Si4Cl10, NSi4Cl11, N2Si4Cl12, N2Si5Cl14, N3Si6Cl15 (3 isomers), N2Si6Cl16 and some related compounds (NOSi4Cl11, N2O2Si6Cl14, N2OSi5Cl12). GeCl4 shows an similar behaviour. This could be shown by GC/MS‐investigations. The structures of
N2Si5Cl14, N2Si6Cl16 and N3Si6Cl15 have been determined by quantum chemical methods. The angle sums around the N atoms are close to 360°.
Ein ungewöhnliches biphenylsubstituiertes Lithiumchlorotriarylsamarat
Authors: Niemeyer Mark
Published: May 2005

An Unusual Biphenylsubstituted Lithiumchlorotriarylsamarate

The reaction of the lithium biphenyl LiPmph (Pmph = 2′,3′,4′,5′,6′‐pentamethylbiphenyl) with samarium trichloride in a molar ratio of 3 to 1 affords under elimination of only 2 equivalents lithium chloride the lithium samarate [(thf)3Li][ClSm(Pmph)3(thf)] in a yield of 45°. In the obtained contact ion pair the samarium atom shows an only slightly distorted trigonal bipyramid coordination. Equatorial and axial positions are occupied by three propeller like arranged biphenyl substituents, the Cl{···Li(thf)3} ligand, and a THF molecule, respectively. A rather unusual folding of the aryl ligands leads to comparably short distances of the Sm atom to the ortho‐C–H‐bonds and therefore to the formation of strong agostic interactions.
Steering of Configuration by (2‐Phosphanyl)phenolato Ligands in Trimethylphosphane Iron Complexes
Authors: Klein Hans‐Friedrich , Frey Markus , Mao Shizhen
Published: May 2005

(Diphenylphosphanyl)phenols C6H3(1‐OH)(2‐PPh2)(4‐R1)(6‐R2), abbreviated as (P∧OH), oxidatively add to Fe(PMe3)4 affording hydridoiron(II) compounds fac‐FeH(P∧O)(PMe3)3 (1: R1=R2=H; 2: R1=Me, R2=H; 3: R1=OMe, R2=H; 4: R1=Me, R2=CMe3; 5: R1=R2=CMe3) with high stereoselectivity. (2‐diphenylphosphanyl)thiophenol (P∧SH) reacts accordingly forming fac‐FeH(P∧S)(PMe3)3 (9). Complete assignment of 1H, 13C, and 31P signals is achieved by 2D heteronuclear shift correlations. 4,6‐Di‐tert‐butyl‐(2‐diphenylphosphanyl)phenol reacts with FeI(Me)(PMe3)4 to form FeI(P∧O)(PMe3)2 (6). 4, 5 and 9 under 1 bar of CO are converted to monocarbonyl derivatives FeH(P∧X)(CO)(PMe3)2 (7, 8: X = O; 10: X = S) which in solution form mixtures of two isomers A and B. 4 and 5 react with their parent phosphanylphenols, respectively, to give diamagnetic complexes Fe(P∧O)2(PMe3) (11, 12) which dissociate trimethylphosphane to give paramagnetic compounds Fe(P∧O)2. The same phosphanylphenols react with FeCl3 to afford racemic mixtures of complexes Fe(P∧O)3 (13, 14). Structural data were also obtained from single crystals of compounds 1, 5, and 11.
Drei neue Ethanidiodide des Lanthans: La5I9(C2), La6I10(C2) und La10I15(C2)2
Authors: Mattausch Hansjürgen , Hoch Constantin , Simon Arndt
Published: May 2005

Three New Ethanide Iodides of La: La5I9(C2), La6I10(C2) and La10I15(C2)2

The reaction of La, LaI3 und C (4 : 5 : 3) yields the unknown compounds La5I9(C2) at 800 °C, La6I10(C2) at 850 °C, and La10I15(C2)2 at 900 °C. They crystallize in the triclinic space group $P{\bar 1}$ with a = 8.006(2) Å, b = 10.088(2) Å, c = 14.383(3) Å, α = 79.34(3)°, β = 80.75(2)° and γ = 85.07(3)° for La5I9(C2), a = 9.687(1) Å, b = 9.728(1) Å, c = 7.955(1) Å, α = 97.34(1)°, β = 105.56(1)° and γ = 107.81(1)° for La6I10(C2) and a = 9.747(1) Å, b = 10.655(1) Å, c = 11.736(1) Å, α = 93.68(1)°, β = 114.44(1)° and γ = 109.28(1)° for La10I15(C2)2. As characteristic building units the crystal structure of La5I9(C2) contains trigonal bipyramids of La atoms, La6I10(C2) La octahedra, and La10I15(C2)2 La double octahedra. These La building units are centered by C2 dumbbells with d(C‐C) ranging from 1.41(1) Å to 1.47(1) Å. The black compounds are sensitive to moisture.
Bis–(5,5′–diethylbarbiturato) Copper(II) and Cadmium(II) Complexes with Ethylenediamine. Synthesis, Crystal Structures, Spectroscopic and Thermal Characterization of cis–[Cu(barb)2(en)] and {[Cd(barb)2(μ–en)]·2H2O}n
Authors: Yilmaz Fatih , Yilmaz Veysel T. , Kazak Canan
Published: May 2005

Two new bis(5,5′–diethylbarbiturato) (barb) complexes of copper(II) and cadmium(II) with ethylenediamine (en) were synthesized and characterized by elemental analysis, FT–IR spectroscopy and thermal analysis. In addition, their solid–state structures were determined by single crystal X–ray diffraction studies. cis–[Cu(barb)2(en)] (1) crystallizes in the monoclinic space group of C2/c and consists of neutral monomeric units, in which the copper(II) ion exhibit a highly distorted octahedral coordination by two barb anions and a neutral chelating en ligand. The individual molecules of 1 are held together by N–H···O hydrogen bonds, forming a three–dimensional network. {[Cd(barb)2(μ–en)]·2H2O}n (2) is a one–dimensional coordination polymer and also crystallizes in the monoclinic crystal system (P21/c). In 2, [Cd(barb)2(en)] building blocks are connected into a chain by bridging NH2 groups of en, and the individual chains are further stacked by O–H···O and N–H···O hydrogen bonds to form a three–dimensional supramolecular framework. The barb ligands in both complexes act as a bidentate ligands via the negatively charged imino N atom and one of the carbonyl O atoms adjacent to the imino N atom. The M–O bond distances in both complexes are much longer than M–N bond distances, indicating a weak interaction of the carbonyl group of barb.
Coordination Chemistry of Acrylamide: 1. Cobalt(II) Chloride Complexes with Acrylamide – Synthesis and Crystal Structures
Authors: Girma K. B. , Lorenz Volker , Blaurock Steffen , Edelmann Frank T.
Published: May 2005

The molecular structures of blue dichloro‐tetrakis(acrylamide) cobalt(II), [Co{O‐OC(NH2)CH=CH2}4Cl2] (1) and pink hexakis(acrylamide)cobalt(II) tetrachlorocobaltate(II), [Co{O‐OC‐(NH2)CH=CH2}6][CoCl4] (2), characterized by single X‐ray diffraction, IR spectroscopy and elemental analyses, are described. The coordination of CoII in 1 involves a tetragonally distorted octahedral structure with four O‐donor atoms of acrylamide in the equatorial positions and two chloride ions in the apical positions. The second complex 2 in ionic form contains CoII cations surrounded by an octahedral array of O‐coordinated acrylamide ligands, accompanied by a [CoCl4]2− anion.
Reaktive E=C(p‐p)π‐Systeme. 54 [1] Reaktionen des Perfluor‐2‐arsapropens, F3CAs=CF2 (1), mit H‐aciden Verbindungen Me2EH (E = N, P, As) und MeE′H (E′ = O, S, Se)
Authors: Albers Thomas , Grobe Joseph , Maulitz Andreas H. , Würthwein Ernst‐Ulrich
Published: May 2005

Reactive E=C(p‐p)π‐Systems. 54 [1] Reactions of perfluoro‐2‐arsapropene, F3CAs=CF2 (1), with H‐acidic compounds Me2EH (E = N, P, As) and MeE′H (E′ = O, S, Se)

The reactions of the perfluoro‐2‐arsapropene (1) with H‐acidic compounds Me2EH (E = N, P, As) and MeE′H (E′ = O, S, Se), respectively, proceed via addition to the As=C double bond yielding either secondary arsanes F3C(H)AsCF2X (X = NMe2, PMe2, OMe, SMe) or AsX derivatives (X = AsMe2, SeMe). Me2‐AsH is obviously a border case nucleophile because, besides the AsX derivative as main product, small amounts of the arsane are formed indicative for the reverse addition pathway. With the strong base Me2NH, the addition is followed immediately by HF elimination producing the fairly stable arsaalkene F3CAs=C(F)NMe2 (4) which had already been obtained by reaction of HAs(CF3)2 with three equivalents of Me2NH. The novel rather labile compounds were identified by spectroscopic (NMR, GC/MS) investigations. – Quantum chemical DFT calculations [B3LYP/6‐311+G(d,p)] were carried out to determine the relative energy of the isomeric products and the thermodynamics of the addition reactions.
(A19N7)[In4]2 (A = Ca, Sr) and (Ca4N)[In2]: Synthesis, Crystal Structures, Physical Properties, and Chemical Bonding
Authors: Kirchner Martin , Schnelle Walter , Wagner Frank R. , Kniep Rüdiger , Niewa Rainer
Published: May 2005

Single phase powders of (A19N7)[In4]2 (A = Ca, Sr) and (Ca4N)[In2] were prepared by reaction of melt beads of the metallic components with nitrogen. The crystal structure of (Ca19N7)[In4]2 was refined based on neutron and X‐ray powder diffraction data. The crystal structure of (Sr19N7)[In4]2 was solved from the X‐ray powder pattern. The structure refinements in combination with results from chemical analyses ascertain the compositions. The compounds (A19N7)[In4]2 (A = Ca, Sr) are isotypes of (Ca19N7)[Ag4]2; (Ca19N7)[In4]2 is probably identical to the earlier reported (Ca18.5N7)[In4]2. The crystal structure of the isotypes (A19N7)[In4]2 (A = Ca, Sr; cubic, $Fm{\bar 3}m$, Ca: a = 1471.65(3) pm; Sr: a = 1561.0(1) pm) contains isolated [In4] tetrahedra embedded in a framework of edge‐ and vertex‐sharing (A6N) octahedra. Six of these octahedra are condensed by edge‐sharing around one central A2+ ion to form “superoctahedra” (A19N6) which are connected three‐dimensionally via further octahedra by corner‐sharing. The crystal structure of (Ca4N)[In2] (tetragonal, I41/amd, a = 491.14(4) pm, c = 2907.7(3) pm) consists of alternating layers of perovskite type slabs of vertex‐sharing octahedra (Ca2Ca4/2N) and parallel arranged infinite zigzag chains [In2]. In the sense of Zintl‐type counting the compounds (A2+)19(N3−)7[(In2.125−)4]2 present an electron excess, (Ca2+)4(N3−)[(In2.5−)2] is electron deficient. Metallic properties are supported by electrical resistivity and magnetic susceptibility measurements. The analysis of the electronic structures gives evidence for the existence of homoatomic interactions In–In and significant heteroatomic metal–metal interactions Ca–In which favor the deviations of the title compounds from the (8 – N) rule.
Supramolecular Assembling through Anionic Iodine Secondary Bonds: Synthesis and X‐ray Characterization of (Et4N)[PhTeI4] and (Et4N)[(β‐Naphthyl)TeI4]
Authors: Schulz Lang Ernesto , Manzoni de Oliveira Gelson , Nanci Ledesma Gabriela
Published: May 2005

[PhTe]2 and [(β‐naphthyl)Te]2 react with iodine and tetraethylammonium iodide in toluene/methanol to give (Et4N)[PhTeI4] and (Et4N)[(β‐Naphthyl)TeI4]. The complexes were analysed by single crystal X‐ray diffraction affording the centrosymmetric monoclinic space group P21/c. In the novel compounds only anionic interactions of the types Te···I and I···I take place, cation‐anion effective contacts do not occur. Both anions [PhTeI4] and [(β‐naphthyl)TeI4] exhibit square pyramidal coordination at tellurium, with the iodine atoms in the basal positions and the organic groups apical. The tellurium centers achieve an octahedral coordination in the whole lattices through Te···I secondary bonds with the adjacent ionic species. Only the Te–I‐ and I–I‐secondary bonds behave as structure‐forming interactions in the self‐organization of the supramolecular anionic gatherings. New evidences show that for organyltellurates (Q)[PhTeX4] (Q = protonated amines, amides or amino acids; X = Cl, Br, I), NH···X hydrogen bondings are able to hinder the anionic halogen‐halogen secondary interactions. In case of the more frequent I···I interactions, they have been observed only in the absence of NH···I hydrogen bonds.