Ingo Pantenburg

Syntheses and Properties of Tetrakis(pentafluorophenyl)tellurium, Te(C6F5)4, and Related Compounds — Single Crystal Structures of Tris(pentafluorophenyl)tellurium Bromide, Te(C6F5)3Br, Tris(pentafluorophenyl)tellurium Trifluoromethanesulfonate, [Te(C6F5)3][OSO2CF3], and Bis(pentafluorophenyl)tellurium Oxide, Te(C6F5)2O

Te(C6F5)4 was prepared from the reactions of TeCl4 or Te(C6F5)2Cl2 with Grignard reagents or AgC6F5 in moderate to good yields. Substitution reactions with Me3SiX (X = Cl, Br, OSO2CF3), with equimolar amounts of Br2, with AgNO3 and with H[BF4] or BF3·OEt2 yielded the Te(C6F5)3X derivatives (X = Cl, Br, OSO2CF3, NO3, BF4). Oxidation reactions of Cd, Hg, and Pd0 complexes led to Te(C6F5)2 and the corresponding bis(pentafluorophenyl) derivatives M(C6F5)2 (M = Cd, Hg, Pd) and with InBr to In(C6F5)2Br. From very slow hydrolysis of Te(C6F5)4 the oxide Te(C6F5)2O was prepared. The thermal decomposition, the NMR and mass spectra of the partially new compounds are discussed. The crystal structures of Te(C6F5)3Br (monoclinic, P21/a, Z = 4), [Te(C6F5)3][OSO2CF3] (monoclinic, P21/n, Z = 16) and [Te(C6F5)2O]2 (triclinic, P1¯, Z = 2) were determined. Die Synthesen und Eigenschaften von Tetrakis(pentafluorphenyl)tellur, Te(C6F5)4, und verwandten Verbindungen — Rontgenstrukturanalysen von Tris(pentafluorphenyl)-tellurbromid, Te(C6F5)3Br, Tris(pentafluorphenyl)tellurtrifluormethansulfonat, [Te(C6F5)3][OSO2CF3] und Bis(pentafluorphenyl)telluroxid, Te(C6F5)2O Te(C6F5)4 wurde durch die Umsetzungen von TeCl4 bzw. Te(C6F5)2Cl2 mit Grignardreagenzien oder AgC6F5 in masigen bis guten Ausbeuten dargestellt. Durch Substitutionsreaktionen mit Me3SiX (X = Cl, Br, OSO2CF3), mit aquimolaren Mengen Br2, mit AgNO3 sowie mit H[BF4] bzw. BF3·OEt2 entstanden die Te(C6F5)3X-Verbindungen (X = Cl, Br, OSO2CF3, NO3, BF4). Oxidationsreaktionen von Cd-, Hg- und Pd0-Komplexen ergaben Te(C6F5)2 und die entsprechenden Derivate M(C6F5)2 (M = Cd, Hg, Pd); InBr wurde zu In(C6F5)2Br oxidiert. Durch sehr langsame Hydrolyse von Te(C6F5)4 wurde Te(C6F5)2O dargestellt. Die thermischen Zersetzungen sowie die NMR- und Massenspektren der teilweise neuen Verbindungen werden diskutiert. Die Kristallstrukturen von Te(C6F5)3Br (monoklin, P21/a, Z = 4), [Te(C6F5)3][OSO2CF3] (monoklin, P21/n, Z = 16) und [Te(C6F5)2O]2 (triklin, P1¯, Z = 2) wurden bestimmt.

Formation of novel anionic gold–tin cluster compounds

A straightforward procedure for the formation of mixed metal Au/Sn clusters is presented: reaction of the heteroborate [SnB11H11]2- with phosphine gold electrophiles gave the clusters [Bu3NH]3[{(Et3P)Au(SnB11H11)}3] and [Bu3MeN]4[{(dppm)Au2(SnB11H11)2}2], which were characterised by X-ray diffraction.

Stannaborate Transition Metal Chemistry: Ligand Properties, Reactivity, and Density Functional Theory Calculations of Platinum and Palladium Complexes

Three stannaborate complexes of platinum(II) and a novel stannoborate palladium(II) derivative have been prepared in excellent yield. The tin transition metal bond is formed through nucleophilic substitution and the resulting complexes [Bu3MeN] [trans-[(Et3P)2Pt(SnB11H11)H]] (6), [trans-[(Et3P)2Pt(SnB11H11)(CNtBu)]] (7), [Bu3MeN]2[trans-[(Et3P)2Pt(SnB11H11)2-(CNtBu)]] (8), and [Bu3MeN][(dppe)-Pd(SnB11H11)Me] (12) (dppe = 1,2-bis-(diphenylphosphanyl)ethane) were characterized by NMR spectroscopy and elemental analysis. In the cases of the zwitterion 7, the pentacoordinated complex 9, the palladium salt 12 and [(triphos)Pt(SnB11H11)] (10) (triphos = 1,1,1-tris(diphenylphosphanylmethyl)ethane), their solid-state structures are determined by X-ray crystal structure analyses. The trans influence of the [SnB11H11] ligand is evaluated from the results of the IR spectroscopy and X-ray crystallographic structures of complexes 6, 7, and 12. The dipole moment of the zwitterion 7 is calculated by density functional theory (DFT) methods. The alignment of the dipole moments of the polar molecules 7 and 12 in the solid state is discussed.

Noncentrosymmetric coordination networks based on nitrate and acetylenedicarboxylate anions

Abstract Single crystals of Ba2(ADC)(NO3)2 · 4 H2O (1), Ba7(ADC)6(NO3)2 · 14 H2O (2), and Ba3(ADC)2Cl(NO3) × 5 H2O (3) were prepared by crystallisation at the phase boundary of a two phase system (ADC = C2(COO)2). They crystallize in noncentrosymmetric space groups (1: C2221, Z = 4; 2: I2, Z = 2; 3: P2212, Z = 2). For 1 a SHG signal of approx. 0.29 KDP (1 KDP = SHG of KH2PO4) was determined. All hitherto known compounds of the almost linear dianion of acetylenedicarboxylic acid crystallize in centrosymmetric space groups, but by inserting trigonal planar nitrate anions into the crystal structure a symmetry breaking seems to occur, which leads to noncentrosymmetric crystal structures. Several examples from the literature show that this observation might be also valid for other compounds.

[Ba(Benzo-15-Krone-5)2](In)2: Darstellung und strukturelle Charakterisierung eines Triiodids (n = 3) und eines Heptaiodids (n = 7)

[Ba(benzo-15-crown-5)2](I3)2 and [Ba(benzo-15-crown-5)2](I7)2 can be obtained in crystalline form by reacting benzo-15-crown-5 (C14H20O5), barium iodide (BaI2), and iodine (I2) in ethan-ole /dichloromethane. The triiodide consists of a sandwich-like cation [Ba(benzo-15-crown-5)2]2+ and an isolated symmetrically linear I3- anion. The unusual I7- anion in the heptaiodide can be described as a V-shaped pentaiodide unit, which is connected with a slightly widened iodine molecule to the rare Z-form of the heptaiodide ion. In the crystal structure, secondary bonding distances lead to almost planar ten-membered iodine rings, which are connected by common edges to form staircase-like bands.

Syntheses and crystal structures of bis(4-dimethylaminopyridine) group 12 trifluoroacetates — M(OCOCF3)2·2DMAP (M=Zn, Cd, Hg)

Abstract Bis(4-dimethylaminopyridine) group 12 trifluoroacetates—M(OCOCF 3 ) 2 ·2DMAP (M=Zn, Cd, Hg) were prepared in quantitative yields from the anhydrous metal trifluoroacetates and DMAP. All compounds crystallize in the triclinic space group P 1 (no. 2) with two molecules per unit cell. While Zn(OCOCF 3 ) 2 ·2DMAP is built up by well-separated tetrahedral units exhibiting strongly covalent ZnO bonds to monodentate trifluoroactate groups, Cd(OCOCF 3 ) 2 ·2DMAP and Hg(OCOCF 3 ) 2 ·2DMAP form dimeric units. The metal centers are distorted octahedrally surrounded by two axial DMAP ligands, two ionic bridging and one chelating trifluoroacetate group.

Synthesis and structure of [Zr{η5:η1-C9H6B(NiPr2)NPh}2]: a new complex with a boron-bridged amido-indenyl ligand

A boron-bridged amido-cyclopentadienyl ligand was recently shown to form constrained-geometry titanium-complexes that are capable of olefin polymerisation. Here, the synthesis of the corresponding amido-indenyl ligand η 1 -C 9 H 7 B(N i Pr 2 )N(H)Ph (C 9 H 7 =indenyl) ( 2a / 2v ) and its allyl–vinyl isomerisation are discussed. Deprotonated 2a reacts with ZrCl 4 to give the strongly distorted zirconocene-type complex [Zr{η 5 :η 1 -C 9 H 6 B(N i Pr 2 )NPh} 2 ] ( 3 ) in a 2:1 reaction. All compounds have been characterised by multinuclear NMR methods and structures of both the ligand 2a and the complex 3 have been confirmed by X-ray diffraction.

Synthesis and Structure of [Hg{OP(O)CF3(OH)}2(PMe3)3], a Distorted Trigonal Bipyramidal Complex Connected by Hydrogen Bridges to Polymeric Chains†

The hydrolysis of [Hg{P(CF3)2}2(PMe3)2] yields colourless crystals of [Hg{OP(O)CF3(OH)}2(PMe3)3]. The proposed multistep reaction proceeds via primary hydrolysis of the starting material giving HgO and HP(CF3)2. The latter is directly oxidized by HgO to (CF3)2P(O)OH. The bis(trifluoromethyl)phosphinic acid hydrolyses to CF3P(O)(OH)2 which reacts with [Hg{P(CF3)2}2(PMe3)2] in the presence of PMe3 to the title compound. The crystal structure was determined by X-ray single-crystal analysis (triclinic; P1¯; a = 860.7(1), b = 1007.6(2), c = 1625.0(3) pm; α = 96.09(2), β = 101.09(2), γ = 107.79(2)°; Z = 2) and exhibits distorted trigonal bipyramidal mercury complexes which are connected to polymeric chains. The acidic units, {OP(O)CF3(OH)}—, are connected via intermolecular hydrogen bridges, forming two individual centrosymmetric eight membered rings with asymmetric hydrogen bridges with O—O distances of 249.4(8) and 250.8(8) pm. Synthese und Struktur von [Hg{OP(O)CF3(OH)}2(PMe3)3], ein verzerrt trigonal-bipyramidaler Komplex, der uber Wasserstoff-Brucken zu polymeren Ketten verknupft ist Bei der Hydrolyse von [Hg{P(CF3)2}2(PMe3)2] werden farblose Kristalle der Verbindung [Hg{OP(O)CF3(OH)}2(PMe3)3] erhalten. Der vorgeschlagene Reaktionsmechanismus der Hydrolyse verlauft uber die intermediare Bildung von HgO and HP(CF3)2. Letzteres wird durch HgO zu (CF3)2P(O)OH oxidiert. Die entstehende Bis(trifluormethyl)phosphinsaure hydrolysiert zu CF3P(O)(OH)2, welches in der Gegenwart von PMe3 mit [Hg{P(CF3)2}2(PMe3)2] zur Titelverbindung reagiert. Die Einkristall-Struktur-Analyse (triklin; P1¯; a = 860.7(1), b = 1007.6(2), c = 1625.0(3) pm; α = 96.09(2), β = 101.09(2), γ = 107.79(2)°; Z = 2) beschreibt verzerrt trigonal-bipyramidale Quecksilber-Komplexe, die zu polymeren Ketten verknupft sind. Die sauren Einheiten {OP(O)CF3(OH)}— sind uber intermolekulare, asymmetrische Wasserstoff-Brucken mit O—O Abstanden von 249.4(8) und 250.8(8) pm verknupft, die mit der Bildung von zwei individuellen, zentrosymmetrischen, achtgliedrigen Ringen einhergeht.

Untersuchungen an Polyhalogeniden, XXXXII [1]. Das Pentaiodid-Ion I5-; Eine Übersicht: Darstellung und Kristallstruktur der Verbindung [Rb(C16H24O6)](I5) · H2O

Abstract [Rb(benzo-18-crown-6)](I5) H2O could be prepared by the reaction of benzo-18-crown-6, rubidium iodide, and iodine in ethanol / dichloromethane. It crystallizes in the monoclinic space group P21/a with a = 1881.8(3), b = 1439.0(2), c = 2269.0(3) pm, ß = 111.24(1)° and Z = 8. The crystal structure was refined to RF = 0.038 for 5310 reflections. It contains two independent molecules. The two cations and the coordinating water molecules form a zigzag chain running along [100] paralleled by two structurally similar pentaiodide chains with one leg of the V-shaped pentaiodide ion forming the backbone of the chain. In both cases the other leg stands out in a novel fashion without forming a coplanar cis or trans configuration known from other pentaiodides. Anionic motifs of other crystalline pentaiodides are summarized and discussed.

Isolated pentaiodide anions in [K(18‐crown‐6)]I5

(1,4,7,10,13,16-Hexaoxacyclooctadecane-kappa(6)O)potassium pentaiodide, [K(C(12)H(24)O(6))]I(5), obtained by slow evaporation of an ethanol solution of KI, 18-crown-6 and I(2), contains [K(18-crown-6)](+) cations (C(i) symmetry) and I(5)(-) anions (C(2) symmetry), which are arranged in alternating layers parallel to (001). In contrast to the well known tendency of I(5)(-) ions to form chains and nets, the I(5)(-) units in the title compound are isolated.