Strukturen der Alkalimetallsalze aromatischer,heterocyclischer Amide: Synthese und Struktur von Kronenether‐Addukten der Alkalimetall‐indolide

Structures of Alkali Metal Salts of Aromatic, Heterocyclic Amides: Synthesis and Structure of Crown Ether Adducts of the Alkali Metal Indolides The synthesis of five alkali metal indolide crown ether complexes is reported. Lithium‐indolide(12‐crown‐4) ( 1 ) was synthezised from butyllithium, indole, and 12‐crown‐4; sodium‐indolide(15‐crown‐5) ( 2 ) from sodium metal, indole, and 15‐crown‐5; potassium‐indolide(18‐crown‐6) ( 3 ) from potassium hydride, indole, and 18‐crown‐6. Rubidium‐ and cesium‐indolide(18‐crown‐6) ( 4 , 5 ) were made from Rb‐ and Cs‐hexamethyldisilazide, indole, and 18‐crown‐6. The structures of 2 , 4 , and 5 could be determined by X‐ray diffraction. The complexes 2 and 4 are mononuclear, the indolide anion shows an η¹(N)‐coordination to the metal cation. Complex 5 is dinuclear with a central [Cs—N—]₂‐ring.     

Strukturen von polaren Magnesiumorganylen: Synthese und Struktur von Basen‐Addukten des Bis(cyclopentadienyl)magnesiums

Structures of Polar Magnesium Organyls: Synthesis and Structure of Base Adducts of Bis(cyclopentadienyl)magnesium Eight donor‐acceptor complexes of bis(cyclopentadienyl)magnesium ( 1 ) with N‐ and O‐donor Lewis bases have been synthesized and characterized by X‐ray structure analysis. With acetonitrile, dimethoxyethane, diethyleneglycoldimethylether, dioxane, and tetramethylethylenediamine simple 1:1 adducts are formed ( 2 – 6 ). In some cases a change of the hapticity of one cyclopentadienylring from η⁵ to η² or η¹ is observed ( 4 – 6 ). In the adduct with pentamethyldiethylenetriamine ( 7 ) one C₅H₅‐ring is removed from the magnesium atom forming the cation [Mg(C₅H₅)(PMDTA)]⁺ and an uncoordinated five‐ring anion. With the crown ether 15‐crown‐5 the two ionic Mg compounds 8 and 9 are formed which have a [Mg(15‐crown‐5)L₂]²⁺‐cation [L = pyridine, THF] and two uncoordinated cyclopentadienyl anions. Cyclopentadienyl‐methyl‐magnesium reacts with 15‐crown‐5 to the salt [Mg(CH₃)(15‐crown‐5)]⁺ C₅H₅^? ( 10 ) which has also a free cyclopentadienyl anion.     

Strukturen von polaren Magnesiumorganylen: Synthese und Struktur von Basen‐Addukten des Magnesiumindenids

An improved X‐ray structure determination of magnesium indenide Mg(C₉H₇)₂ ( 1 ) at low temperature was carried out. Four donor‐acceptor complexes of Mg(C₉H₇)₂ ( 1 ) with O‐ and N‐donor Lewis bases were synthesized and characterized by X‐ray structure analysis. With dioxane and tetramethylethylenediamine (TMEDA) two simple monomeric complexes, [Mg(C₉H₇)₂(dioxane)₂]·1.5dioxane ( 2a ) and [Mg(C₉H₇)₂(TMEDA)] ( 3 ), were formed. With the O‐donors tetrahydrofuran (THF) and dimethylsulfoxide (DMSO) two ionic magnesium compounds 4 and 5 could be synthesized which have a [MgL₆]²⁺ cation [L = THF and DMSO] and two uncoordinated indenide anions.     

Hochdruck‐Synthese,Kristallstruktur und Eigenschaften von NaPN2

High‐Pressure Synthesis, Crystal Structure, and Properties of NaPN₂ Single phase NaPN₂ was synthesized by the reaction of NaN₃ and P₃N₅ in a multianvil assembly at 3 GPa and 1000 °C. The title compound crystallizes in a variant of the chalcopyrite structure type and is isotypic to LiPN₂. The crystal structure was refined by the Rietveld method (I 4 2d, a = 497.21(2), c = 697.60(3) pm, Z = 4, 36 observed reflections, R_p = 0.0502, wR_p = 0.0649, R_F = 0.0788).     

Kristall- und Molekülstruktur der solvatfreien Hexamethyldisilazide des Rubidiums und Caesiums und die Kristallstruktur eines Toluolsolvates

Crystal and Molecular Structure of the Solventfree Hexamethyldisilazides of Rubidium and Cesium and the Crystal Structure of a Toluene Solvate X-ray crystal structures are reported for the dimeric rubidium and cesium hexamethyldisilazides [MN(SiMe₃)₂]₂. [RbN(SiMe₃)₂]₂ ( 1 ) crystallizes in the monoclinic space group P2₁/c with a = 1044.7(2), b = 891.1(2), c = 1281.0(3) pm, β = 100.26(2) °, Z = 2. [CsN(SiMe₃)₂]₂ ( 2 ) crystallizes in the orthorhombic space group Pbca with a = 1270.81(2), b = 1281.16(1), c = 1539.65(2) pm, Z = 4. Both compounds contain a four-membered [M–N–]₂-ring located on an inversion centre. The M–N bond lengths are: 287.8(2), 295.6(2) pm ( 1 ) and 307.4(2), 314.9(2) pm ( 2 ). The solvate [CsN(SiMe₃)₂]₂ · C₇H₈ ( 3 ) crystallizes from toluene in the triclinic space group P1 with a = 854.00(2), b = 979.58(2), c = 1084.45(3) pm, α = 111.482(1), β = 93.821(1), γ = 108.546(1)°, Z = 1. In this compound dimeric units [CsN(SiMe₃)₂]₂ and toluene molecules form a polymeric chain.     

Alkaliisocyanacetate. Synthese und Struktur von [K(18‐Krone‐6)](O2CCH2NC)

Alkali‐isocyanoacetates. Synthesis and Structure of [K(18‐crown‐6)](O₂CCH₂NC) The alkali isocyanoacetates M⁺[O₂CCH₂NC]^? (M = Li,Na,K,Cs) ( 1a ‐ d ) are synthesized by reaction of ethyl isocyanoacetate with the respective alkali hydroxides in ethanol and characterized by IR, NMR (¹H, ¹³C), and mass spectrometry (FAB). In alcoholic solution as well as in the gas phase ion pairs and higher aggregated species are observed. In contrast, [K(18‐crown‐6)][O₂CCH₂NC] ( 2 ) which is obtained from 1c and 18‐crown‐6, turns out to be a 1:1 electrolyte in solution (acetone); in the solid, the isocyanoacetate anion binds to K⁺ via the two carboxylate oxygen atoms resulting in an O₈‐coordinated metal atom.     

Synthese und Struktur C,N‐difunktionalisierter Sulfinimidamide

Synthesis and Structure of C,N‐difunctionalized Sulfinimideamides Sulfurdiimides RN=S=NR ( 1 a , b ) react in diethyl ether with two equivalents of lithiummethyl to give dimeric C,N‐dilithiummethylenesulfinimideamide ether adducts {Li₂[H₂C–S(NR)₂ · Et₂O]}₂ ( 2 a , b ) ( a : R = ^tBu, b : R = SiMe₃). Metathesis of 2 b with four equivalents of Me₃SiCl, Me₃SnCl or Ph₃SnCl yields the corresponding C,N‐bis‐substituted sulfinimideamides R₃EH₂C–S[N(SiMe₃)₂]NER₃ ( 3 – 5 ) ( 3 : R = Me, E = Sn; 4 : R = Ph, E = Sn; 5 : R = Me, E = Si). The crystal structures of 2 a and 2 b were determined by X‐ray structure analysis. Both compounds form centrosymmetric cage structures consisting of two distorted face sharing cubes ( 2 a : space group P1 (No. 2); Z = 2 (4 · 0,5); 2 b : space group C2/c (No. 15), Z = 4).     

Synthese,spektroskopische Charakterisierung und Molekülstrukturen ausgewählter Lewis‐Basen‐Addukte der Alkalimetall‐tri(tert‐butyl)silylphosphanide

Synthesis, Spectroscopic Characterization, and Molecular Structures of Selected Lewis‐Base Adducts of the Alkali Metal Tri(tert‐butyl)silylphosphanides The metalation of tri(tert‐butyl)silylphosphane with butyllithium and the bis(trimethylsilyl)amides of sodium, potassium, and rubidium yields quantitatively the corresponding alkali metal tri(tert‐butyl)silylphosphanides, which crystallize after addition of appropriate Lewis‐bases as dimeric (DME)LiP(H)SitBu₃ ( 1 ), chain‐like (DME)NaP(H)SitBu₃ ( 2 ), monomeric ([18]Krone‐6)KP(H)SitBu₃ ( 3 ), and dimeric (TMEDA)_1.5RbP(H)SitBu₃ ( 4 ). The reaction of H₂PSitBu₃ with cesium bis(trimethylsilyl)amide at room temperature gives monocyclic and tetrameric cesium tri(tert‐butyl)silylphosphanide ( 5 ) with two additional coordinated CsN(SiMe₃)₂ molecules. At 80 °C this complex reacts with excess of phosphane to the tetrameric toluene adduct (η⁶‐Toluol)CsP(H)SitBu₃ ( 6 ) which contains a central Cs₄P₄‐heterocubane fragment. The constitution of these compounds was verified by X‐ray structure determinations.     

TAS‐Indolid und TAS‐Carbazolid: Strukturen von [TAS]+[IndHInd]− und [TAS]+[Carb]−·½CarbH

TAS Indolide and TAS Carbazolide: Structures of [TAS]⁺[IndHInd]^? and [TAS]⁺[Carb]^?·½CarbH From the reaction of TAS‐fluoride [(Me₂N)₃S]⁺[Me₃SiF₂]^? with trimethylsilyl‐indole and trimethylsilyl‐carbazole TAS‐indolide and TAS‐carbazolide are formed. During crystallisation partially protonation to indole and carbazole occurs, resulting in the formation of [TAS]⁺[IndHInd]^? ( 3a ) and [TAS]⁺[Carb]^?·½CarbH ( 5a ) according to X‐ray analysis.     

Kristallstrukturen „supramolekularer”︁ (Benzo‐18‐krone‐6)kaliumtetrathiocyanatometallate: Ein dimerer Komplex {[K(Benzo‐18‐krone‐6)]2[Hg(SCN)4]}2 und zwei isomere Komplexe [K(Benzo‐18‐krone‐6)][Cd(SCN)3] mit kettenförmigen Trithiocyanatocadmat‐Anionen

Crystal Structures of „Supramolecular”︁ Benzo‐18‐crown‐6 Potassium Tetrathiocyanato Metallates: A Dimeric Complex {[K(Benzo‐18‐crown‐6)]₂[Hg(SCN)₄]}₂ and Two Isomeric Complexes [K(Benzo‐18‐crown‐6)][Cd(SCN)₃] Containing Trithiocyanato Cadmate Anions with Chain Structures By reaction of potassium thiocyanatomercurate(II) complexes with benzo‐18‐crown‐6 (2,3‐benzo‐1,4,7,10,13,16‐hexaoxacyclooctadec‐2‐ene) crystals of {[K(benzo‐18‐crown‐6)]₂[Hg(SCN₄)]}₂ ( 1 ) were obtained. 1 crystallizes monoclinic, space group P2₁/n (non‐standard setting of P2₁/c), a = 1737.35(2), b = 1377.16(2), c = 1984.12(3) pm, β = 100.637(1)°, Z = 2. With potassium tetrathiocyanatocadmate(II) two modifications of a complex [K(benzo‐18‐crown‐6)][Cd(SCN)₃] ( 2 , 3 ), of different symmetry were formed. 2 crystallizes monoclinic, P2₁/c, a = 1158,31(3), b = 1096,55(2), c = 2028,46(2) pm, β = 99,5261(2)°, Z = 4, 3  orthorhombic, P2₁cn, a = 1105,95(3), b = 1413,07(4), c = 1617,10(5) pm, Z = 4. 1 has a dimeric structure, built up from a dication K₂(benzo‐18‐crown‐6)₂]²⁺ and two [K(benzo‐18‐crown‐6)]⁺ cations, which are bridged by two [Hg(SCN)₄]^2– anions. In 2 and 3 triply bridged infinite [{Cd(SCN)₃^–}_n] zigzag chains, stretching along screw axes, are to be found as anions. In 2 these chains exist in two conformations related by inversion symmetry, whereas in 3 only one form can be found. [K(benzo‐18‐crown‐6)]⁺ cations are linked to the anion chains via K · · · S interactions of different lengths.     

Synthese,Struktur und Reaktivität von Tris‐, Bis‐ und Mono(2,4‐dimethylpentadienyl)‐Komplexen des Neodyms,Lanthans und des Yttriums

The tris(2,4‐dimethylpentadienyl) complexes [Ln(η⁵‐Me₂C₅H₅)₃] (Ln = Nd, La, Y) are obtained analytically pure by reaction of the tribromides LnBr₃·nTHF with the potassium compound K(Me₂C₅H₅)(thf)_n in THF in good yields. The structural characterization is carried out by X‐ray crystal structure analysis and NMR‐spectroscopically. The tris complexes can be transformed into the dimeric bis(2,4‐dimethylpentadienyl) complexes [Ln₂(η⁵‐Me₂C₅H₅)₄X₂] (Ln, X: Nd, Cl, Br, I; La, Br, I; Y, Br) by reaction with the trihalides THF solvates in the molar ratio 2:1 in toluene. Structure and bonding conditions are determined for selected compounds by X‐ray crystal structure analysis and NMR‐spectroscopically in general. The dimer‐monomer equilibrium existing in solution was investigated NMR‐spectroscopically in dependence of the donor strength of the solvent and could be established also by preparation of the corresponding monomer neutral ligand complexes [Ln(η⁵‐Me₂C₅H₅)₂X(L)] (Ln, X, L: Nd, Br, py; La, Cl, thf; Br, py; Y, Br, thf). Finally the possibilities for preparation of mono(2,4‐dimethylpentadienyl)lanthanoid(III)‐dibromid complexes are shown and the hexameric structure of the lanthanum complex [La₆(η⁵‐Me₂C₅H₅)₆Br₁₂(thf)₄] is proved by X‐ray crystal structure analysis.     

Wasserstoffbrückenbindungen in den Monoammoniakaten von Kalium‐ und Caesiumamid

Hydrogen Bonds in the Monoammoniates of Potassium and Cesium Amide X‐ray structure determination was carried out on the monoammoniates of potassium and cesium amide. Crystals of KNH₂ · NH₃ were grown from liquid NH₃ at 50 °C > T > 20 °C. They crystallize in the cold part of a pressure resistant glass apparatus. Single crystals of CsNH₂ · NH₃ were obtained by zone‐melting at —30 °C in x‐ray capillaries. The following data characterize the crystal chemistry of the compounds: KNH₂ · NH₃ Cmc2₁, Z = 4 21 °C a = 3, 938(1) Å, b = 10, 983(3) Å, c = 5, 847(1) Å CsNH₂ · NH₃ Pnma, Z = 4 30 °C a = 7, 103(1) Å, b = 5, 390(1) Å, c = 10, 106(2) Å For CsNH₂ · NH₃ all hydrogen atom positions were successfully refined. The structure of both ammoniates may be described by a distorted hexagonal close packed arrangement of cations with the NH₃ molecules in the octahedral and the NH₂^— anions in the trigonal bipyramidal interstices. The three H atoms of the NH₃ molecules are involved in hydrogen bridge bonds to two amide ions with d(N(NH₃)···N(NH₂^—)) = 2.60Å for the K and 3.19Å for the Cs compound and to a further NH₃ molecule with d(N(NH₃)···N(NH₃)) = 2.98Å for the K and 3.56Å for the Cs compound. Structural relationship of the ammoniates to the monohydrates of KOH and RbOH is discussed.     

Carbonat‐Hydrate der schweren Alkalimetalle: Darstellung und Struktur von Rb2CO3 · 1,5 H2O und Cs2CO3 · 3 H2O

Carbonate Hydrates of the Heavy Alkali Metals: Preparation and Structure of Rb₂CO₃ · 1.5 H₂O und Cs₂CO₃ · 3 H₂O Rb₂CO₃ · 1.5 H₂O and Cs₂CO₃ · 3 H₂O were prepared from aqueous solution and by means of the reaction of dialkylcarbonates with RbOH and CsOH resp. in hydrous alcoholes. Based on four‐circle diffractometer data, the crystal structures were determined (Rb₂CO₃ · 1.5 H₂O: C2/c (no. 15), Z = 8, a = 1237.7(2) pm, b = 1385.94(7) pm, c = 747.7(4) pm, β = 120.133(8)°, V_EZ = 1109.3(6) · 10⁶ pm³; Cs₂CO₃ · 3 H₂O: P2/c (no. 13), Z = 2, a = 654.5(2) pm, b = 679.06(6) pm, c = 886.4(2) pm, β = 90.708(14)°, V_EZ = 393.9(2) · 10⁶ pm³). Rb₂CO₃ · 1.5 H₂O is isostructural with K₂CO₃ · 1.5 H₂O. In case of Cs₂CO₃ · 3 H₂O no comparable structure is known. Both structures show [(CO₃^2–)(H₂O)]‐chains, being connected via additional H₂O forming columns (Rb₂CO₃ · 1.5 H₂O) and layers (Cs₂CO₃ · 3 H₂O), respectively.     

Über die Synthese von Tris(trimethylsilyl)silyl-kalium, -rubidium und -caesium und die Molekülstrukturen zweier Toluolsolvate

About the Synthesis of Tris(trimethylsilyl)silyl Potassium, Rubidium and Cesium and the Molecular Structures of two Toluene Solvates . Solventfree tris(trimethylsilyl)silyl potassium ( 1 ), rubidium ( 2 ) and cesium ( 3 ) are obtained by the reaction of the zink group bis[tris(trimethylsilyl)silyl] derivatives with the appropriate alkali metal in n-pentane. Addition of benzene or toluene to the colourless powders yields deeply coloured solutions. From these solutions single crystals of tris(trimethylsilyl)silyl rubidium—toluene (2/1) ( 2 a ) and tris(trimethylsilyl)silyl cesium—toluene (2/3) ( 3 a ) suitable for X-ray structure analysis are iso- lated [ 2a : orthorhombic; P2₁2₁2₁; a = 1 382.1(3); b = 1 491.7(5); c = 2 106.3(6) pm; Z = 4 (dimers); 3a : orthorhombic; P2₁2₁2₁; a = 2 131.0(6); b = 2 833.1(2); c = 925.2(2) pm; Z = 4 (dimers)]. The central structure moieties are folded four-membered Rb₂Si₂ and Cs₂Si₂ rings, respectively. Small Si? Si? Si angles (100 to 104°) on the one hand and extreme highfield ²⁹Si-NMR shifts of the central silicon atoms on the other hand indicate a strong charge transfer from the alkali metal atoms to the tris(trimethylsilyl)silyl fragments, i.e. mainly ionic interactions between alkalimetal and silicon atoms.     

Thiosilicate der Selten‐Erd‐Elemente: III. KLa[SiS4] und RbLa[SiS4] – Ein struktureller Vergleich

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 S^2? 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 S^2? 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 equation/tex2gif-stack-1.gif{La[SiS₄]}^? layers that are separated by the alkali metal cations. In direct comparison the two thiosilicate structures can be regarded as stacking variants.