Charakterisierung der Protonen in polykristallinen Parawolframaten durch 1H‐MAS‐NMR‐Untersuchungen

Characterization of the Protons in Polycrystalline Paratungstates using ¹H MAS NMR Investigations ¹H MAS NMR experiments are used to characterize the non‐acid protons of the anions in polycrystalline paratungstates by means of the measured isotropic chemical shift values. The investigation of various hydrates of ammonium paratungstate allows a direct proof of protons in NH₄ ions and in water molecules while protons of the anions are not detectable. However, for both the potassium and the sodium paratungstates ¹H MAS NMR investigations detected the protons of water molecules and the non‐acid protons of the paratungstate anions. Additional ¹H broad‐line NMR experiments at 173 K support the interpretation of the results obtained by the ¹H MAS NMR investigations. For the NMR signal of the non‐acid protons of the paratungstate anion in the ¹H MAS NMR spectra of the potassium salt line‐splitting appears. This refers to the existence of two nonidentical positions of the protons in the crystal lattice and is in agreement with the results of the X‐ray structural analysis.     

Synthese und strukturelle Charakterisierung von Borsubphthalocyaninaten

Synthesis and Structural Characterization of Boron Subphthalocyaninates Halosubphthalocyaninatoboron, [B(X)_spc] (X = F, Cl, Br) is obtained by heating phthalonitrile with boron trihalide in quinoline (X = F) or the corresponding halobenzene, resp. [B(C₆H₅)_spc] is prepared from phthalonitrile and tetraphenylborate or tetraphenyloboron oxide, resp. [B(OR)_spc] (R = H, CH(CH₃)₂, C(CH₃)₃, C₆H₅) is synthesized by bromide substitution of [B(Br)_spc] in pyridine/HOR. Substitution of [B(Br)_spc] in carboxylic acids yields [B(OOCR)_spc] (R = H, CX₃ (X = H, Cl, F), CH₂X (X = Cl, C₆H₅), C₆H₅). All subphthalocyaninates are characterized electrochemically and by UV‐VIS, IR/FIR, resonance Raman, and ¹H/¹⁰B‐NMR spectroscopy. Typical B–X stretching vibrations are at 622 (X = Br), 950 (Cl), 1063 (F), 1096 cm^–1 (OH) as well as between 1119 and 1052 cm^–1 (OR) resp. 985 and 1028 cm^–1 (OOCR). The difference ν(C=O)–ν(C–O) > 400 cm^–1 confirms the unidentate coordination of the carboxylato ligands. According to the crystal structure analysis of [B(OH)_spc], [B(OH)_spc] · 2 H₂O, [B(C₆H₅)_spc], [B(OC(CH₃)₃)_spc], [B(OOCCH₃)_spc] · 0.5 H₂O · C₂H₅OH and [B(OOCCH₃)_spc] · 0.4 H₂O · 1.1 C₅H₅N the _spc ligand is concavely distorted. This saucer shaped conformation is independent of the acido ligands and the presence of solvate. The outermost C atomes are vertically displaced in part by more than 2 Å from the N_i plane. The B atom is in a distorted tetrahedral coordination geometry. It is displaced by ca 0.64 Å out of the N_i plane towards the acido ligand. The average B–N distance is 1.500 Å, and the B–O distances range from 1.418(5) to 1.473(2) Å.     

Darstellung und Charakterisierung von Lithiumhydrogenphthalocyanin

tPreparation and Characterization of Lithiumhydrogenphthalocyanine Lithiumhydrogenphthalocyanine is obtained by the thermal decomposition of tetraalkylammoniumlithiumphthalocyanines as monoclinic blue needles (a = 19.081(9), b = 4,996(3), c = 14.437(7) Å; β = 119.64(4)° (from powder diffraction data)). The properties, IR and UV-VIS spectra are discussed.     

Darstellung und Eigenschaften von Chromorganylen aus Phillips‐Katalysatoren und Ethylen

Surface Compounds of Transition Metals. XLI [1] Preparation and Properties of Organochromium Compounds by Reaction of Phillips Catalysts with Ethylene Reaction of reduced Phillips catalysts with ethylene at 300 °C deactivates the catalyst; supported organochromium compounds are formed. These can be cleaved from the silica support by HCl and other acids, and transferred into solution by extraction with CH₃OH. Chromatography yields fractions of organochromium compounds which differ by CH₂ moieties. XPS, ^1/2H NMR, and mass spectra as well as magnetic measurements prove that an ensemble of (R_nCp)CrCl₂(CH₃OH) (R_nCp = alkylated cyclopentadienyl) has been formed. The R_nCp ligand results from a chromium‐assisted oxidative coupling of the olefin with or without CC‐cleavage. According to UV/Vis and mass spectroscopy Cl^– and CH₃OH can be substituted for other anions and donor molecules. Without a donor dinuclear, Cl‐bridged molecules are obtained, of which [(1,2,3‐Me₃Cp)CrCl₂]₂ was established by crystal structure analysis. Reaction with O₂ reversibly leads to chromium(V) compounds of the type (R₂Cp)Cr(O)Cl₂.     

Darstellung und spektroskopische Charakterisierung von Carboxylatododecaboraten

Preparation and Spectroscopic Characterization of Carboxylatododecaborates The tetrabutylammonium salt (TBA)₂[B₁₂H₁₂]^2? reacts with formic, acetic, cyanoacetic, phenylacetic, propionic, butyric, and thioacetic acid at temperatures between 80 and 150°C forming the carboxylatododecaborates [(RC(O)O)_n? B₁₂H_{12? n}]^2?, n = 1, 2, [CH₃C(O)S? B₁₂H₁₁]^2?. The isolation of the pure compounds is achieved by ion exchange chromatography on diethylaminoethyl cellulose. In case of the dicarboxylatododecaborates beside the 1,7-isomer predominantly the 1,2-isomer, while 1,2-[(OH)C₆H₅CH₂C(O)O? B₁₂H₁₀]^2? is formed exclusively. The alcaline hydrolysis of [RC(O)O? B₁₂H₁₁]^2? and 1,2-[(OH)C₆H₅CH₂C(O)O? B₁₂H₁₀]^2? results in [(OH)? B₁₂H₁₁]^2? and 1,2-[(OH)₂? B₁₂H₁₀]^2?. All compounds are characterized by their ¹¹B-nmr, ¹³C-nmr and IR spectra. The ¹¹B-nmr signals are assigned by a sheme allowing to establish expected spectra.     

Darstellung und Charakterisierung von amphoteren Polystyrol-Latexverbindungen

Ohne Zusammenfassung     

Zur Darstellung und Charakterisierung von Calciumhydrogensulfaten

Preparation and Characterization of Calcium Hydrogen Sulfate CaSO₄ · H₂SO₄ was identified as calcium hydrogen sulfate whereas CaSO₄ · 3 H₂SO₄ is an adduct of CaSO₄ with H₂SO₄. Depending on the excessive amount of H₂SO₄ both compounds exist side by side up to a temperature of 343 K, whereas above this temperature only Ca(HSO₄)₂ is stable. The DTA curve of Ca(HSO₄)₂ shows two maxima at 488 K and 523 K, according to the separation of H₂O under formation of pyrosulfate and decomposition of this compound under elimination of SO₃. In comparison with other hydrogen sulfates Ca(HSO₄)₂ shows a considerable increased O? H distances. The d-values of Ca(HSO₄)₂ are calculated and represented.     

Darstellung,Eigenschaften und Molekülstrukturen von Alkylaluminiumaminoalkoxidchloriden

Synthesis, Properties, and Molecular Structures of Alkylaluminium Aminoalkoxide Chlorides Alkylaluminium aminoalkoxide chlorides [R(Cl)AlOR*] 1 – 3 have been obtained from the reaction of dialkyl aluminium chlorides R₂AlCl with the respective aminoalkohol HOR* ( 1 : R = Et, OR* = dimethylamino‐1‐propanol; 2 : R = Me, OR* = (+);(–)‐dimethylamino‐2‐propanol; 3 : R = Me, OR* = (S)‐N‐methyl‐2‐pyrrolidinyl‐methanol). The reaction between dimethylaluminium chloride and (S)‐α, α‐diphenyl‐2‐pyrrolidinyl‐methanol (OR* = Dpm) yielded, by contrast, the ionic {[MeAl(OR*)₂AlMe₂]⁺ [MeAlCl₃]^–} complex ( 4 ). 1 – 4 have been characterised by ¹H, ¹³C and ²⁷Al‐NMR spectroscopy. Crystal structures of 1 and of the 1 : 1 solvate of 4 with Et₂O have been determined by X‐ray methods and the absolute structure of 4 was confirmed by refinement of the Flack‐parameter. The dimeric molecules of 1 are composed of two chelating rings linked via an almost planar Al₂O₂ unit and pentacoordination is observed about aluminium. In contrast, each of the two crystallographically independent cation molecules of 4 contains one four‐ and and one five‐coordinate metal centre.     

Darstellung und Charakterisierung einige Thiocyanat- und Selenocyanat-Komplexe von Übergangsmetallen

Some 6:1 thiocyanate complexes of Fe^III, Mo^III, Ru^III, Os^III, Ir^III and some 6:1 or 4:1 selenocyanate complexes of Fe^II, Fe^III, Mo^III, Rh^III, Pd^II, Pt^II, and Au^III have been prepared as salts of large organic cations. The compounds are characterized by their infra-red spectra and by conductance measurements. In particular the linkage property of the thiocyanate and selenocyanate ligand is discussed together with the consequences it has on the AHRLAND -CHATT -DAVIES -PEARSON classification of the central ions.     

Synthese und Charakterisierung von Tetralithiumpentaoxoselenat(VI)

Synthesis and Characterization of Tetralithiumpentaoxoselenate(VI) Pure Li₄SeO₅ was prepared by solid state reaction at 500 °C from a mixture of Li₂O and Li₂SeO₄ in silver crucibles. The crystal structure was solved and refined with x‐ray powder methods (profile matching, C2/c, a = 873.3(1), b = 572.5(1), c = 783.6(1) pm, β = 98.29(1)°, R_p = 0.052, R_wp = 0.066). Li₄SeO₅ contains novel SeO₅^4– anions, which form slightly distorted trigonal bipyramids. All ions are coordinated by 5 ligands in the shape of trigonal bipyramidal polyhedra, according to the formula Li₄^[5]Se^[5]O₅^[5]. From the empirical formula and the coordinaton environments, it is clear that this is an order variant of the A^[5]B^[5] structure type, that was found in the system NaCl by global optimisation methods. The crystal structure is consistent with spectroscopic data (IR, Raman, NMR). The ionic conductivity (σ = 3.34 10^–5 Ω^–1 cm^–1 at 340 °C) of the compound was determined with impedance measurements.     

Darstellung,Kristallstruktur, Schwingungsspektren und Normalkoordinatenanalyse von (Ph4P)2[OsN(N3)5] und 15N‐NMR‐Verschiebungen von Nitridoosmaten(VI,VIII)

Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of (Ph₄P)₂[OsN(N₃)₅] and ¹⁵N NMR Chemical Shifts of Nitridoosmates(VI, VIII) The treatment of (Ph₄P)[OsNCl₄] with NaN₃ yields (Ph₄P)₂[OsN(N₃)₅], which crystal structure has been determined by single crystal X‐ray diffraction analysis (monoclinic, space group P 2₁/a, a = 20.484(6), b = 11.168(1), c = 20.666(4) Å, β = 97.35(3)°, Z = 4). The IR and Raman vibrations were assigned by a normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are f_d(Os≡N) = 8.52, f_d(Os–N^α) = 1.99, f_d(N^α–N^β) = 12.42, f_d(N^β–N^γ) = 12.73 and for the azido ligand in trans‐position to the nitrido group f_d(Os–N^{α ·} ) = 1.84, f_d(N^{α ·} –N^{β ·} ) = 11.91, f_d(N^{β ·} –N^{γ ·} ) = 12.18 mdyn/Å. The ¹⁵N NMR spectra of various nitridoosmates reveal the chemical shifts δ(¹⁵N) for K[OsO₃¹⁵N] = 387.6, K₂[Os¹⁵NCl₅] = 446.7, (Ph₄P)[Os¹⁵NCl₄] = 352.9, [(n‐C₆H₁₃)₄N]₂[Os¹⁵N(N₃)₅] = 307.3 and for [(n‐Pr)₄N]₂[Os¹⁵N(¹⁵NCO)₅] = 483,7 (Os≡N), –417,7 (OsNCO_eq) und –392,8 ppm (OsNCO_ax).     

Synthesen und Reaktionen von Aluminiumalkoxid‐Verbindungen

Syntheses and Reactions of Aluminium Alkoxide Compounds Al(O^cHex)₃ ( 1 ) can be synthesized by the reaction of Al with cyclohexanol under evolving of H₂ in boiling xylene. [Li{Al(OCH₂Ph)₄}] ( 2 ) was obtained by treatment of PhCH₂OH with a 1 M solution of LiAlH₄ in THF. [{(THF)Li}₂{Al(O^tBu)₄}Cl] ( 3 ) is the result of the reaction of four equivalents of LiO^tBu on AlCl₃ in THF. 3 is the educt for the reactions with the Lewis‐acids InCl₃ and FeCl₃ in THF leading to the metalates [{(THF)₂Li}₂{Al(O^tBu)₄}] · [MCl₄] [M = In ( 4 ), Fe ( 5 )]. The attempt to react InCl₃ with four equivalents of LiO^tBu leads to only one isolated and characterized product, the complex [Li₄(O^tBu)₃(THF)₃Cl]₂ · THF ( 6 · THF), which can also be synthesized by the treatment of LiCl with three equivalents of LiO^tBu in THF. 1–6 · THF were characterized by NMR, IR and MS techniques as well as by X‐ray structure determinations. According to them, 1 , which is tetrameric in solution, is the first structurally characterized example of the proposed trimer form of aluminium alkoxides [ROAl{Al(OR)₄}₂] with a central trigonal bipyramidal coordinated Al atom. 2 forms a coordination polymer with a distorted tetrahedral coordination sphere of Li and Al, running along [100]. The trinuclear structure skeleton [{(THF)₂Li}₂{Al(O^tBu)₄}]⁺ is still present in the isotypical metalates 4 and 5 . The counter ions [MCl₄]^– possess nearly T_d symmetry. The remarkable structural motif of 6 · THF are two heterocubanes [Li₄(O^tBu)₃(THF)₃Cl] dimerized by Li–Cl bonds.     

Darstellung,Isolierung und Charakterisierung von Selenan- und Tellurandisulfandiphosphonat

Preparation, isolation, and characterization of Monoseleane and Disulphane-Diphosphonate The barium salts of monoselenane and monotellurane disulphanediphosphonate are isolated in pure state for the first time. They are characterized by analytical data and i.r. spectra.     

Darstellung und NMR-spektroskopische Charakterisierung von konfigurationsstabilen Diorganozinn(IV)-Komplexen RPhSnL mit Zinn als chiralem Zentrum

Synthesis and Characterization of Configurationally Stable Diorganotin(IV) Complexes with Tin as a Chiral Centre Contrary to the high optical stability of tetraorganotin compounds most heteroleptic organic tin compounds are configurationally instable. We report the synthesis and the characterization of some new enantiomeric and diastereomeric diorganotin(IV) complexes of stable configuration with tin as a chiral centre. The stabilization of the chiral tin atom was realized by complexation with tridentate diacidic esterhydrazone ligands H₂L, which prevent an interconversion at the stereogenic centre. Multinuclear NMR-studies in solution demonstrate, that the configuration of the chiral tin center is configurationally stable up to 160°C. The molecular structure of the complexes Neophyl-phenyl-tin-2[(2-methyl-mercaptothiocarbonyl)-hydrazono]propionate II b and (2-Methyl-butyl-1-yl)-phenyl-tin-[S-methyl-β-N-(2-salicylmethylidene)thiocarbazat] III g have been determined by single crystal X-ray diffraction analysis.     

Synthese und Charakterisierung von Natriumcyanamid

Synthesis and Characterization of Sodium Cyanamide The synthesis of Na₂CN₂ was carried out by reaction of sodium amide with sodium hydrogen cyanamide at 200 °C, in vacuum. Single crystals were obtained while heating the product (500 °C, 8 days) in silver crucibles. The title compound was characterised by single crystal X‐ray diffraction and IR‐spectroscopy (C2/m; Z = 2, a = 5.0456(3), b = 5.0010(3), c = 5.5359(3) Å; β = 110.078(5)°; R1 = 3.18%, wR2 = 6.35%, GOF = 1.078). The CN₂^2– units are linear exhibiting a C–N bond length of 1.236(1) Å, while sodium is coordinated by five nitrogen atoms forming a square pyramid. The structural relationships to aristotypic Na₂HgO₂ are pointed out.     

Darstellung,Isolierung und Charakterisierung von Ba@C74

Preparation, Isolation, and Characterization of Ba@C₇₄ For the first time Ba@C₇₄ has been isolated in pure form. The title compound has been isolated from a raw material, produced in a radio‐frequency‐furnace, consisting of a mixture of fullerenes and endohedral Bariumfullerenes. Ba@C₇₄ was separated by two stage sublimation and subsequent high‐performance liquid chromatography (HPLC) using a Buckyprep column. The capacity factor for Ba@C₇₄ is 6.0. Its endohedral character has been deduced from the fragmentation pattern obtained by time‐of‐flight mass spectroscopy while the composition has been confirmed by comparison of calculated and measured isotopic pattern of the parent peak. Further characterization was performed by VIS/NIR‐spectroscopy and electron‐paramagnetic‐resonance spectroscopy (EPR).     

Darstellung und spektroskopische Charakterisierung von Fluortrichlor-arsoniumhexafluoroarsenat,AsFCl3+AsF6−

Preparation and Spectroscopic Characterization of Fluorotrichloroarsonium Hexafluoroarsenate, AsFCl₃⁺AsF₆^? The mixed halide pniktide cation AsFCl₃⁺ is prepared by oxidative fluorination of AsCl₃ with XeF⁺ AsF₆^?. AsFCl₃⁺ AsF₆^? is characterized by IR, Raman, and ¹⁹F-NMR spectroscopy.     

Ferrocenophanes with Interannular Nitrogen–Gallium Bridges. 1,3,2‐Diazagalla‐[3]Ferrocenophanes and an 1‐Aza‐3‐Azonia‐2‐Gallata‐[3]Ferrocenophane. Synthesis and Structure

1,1′‐Bis(trimethylsilylamino)ferrocene reacts with trimethyl‐ and triethylgallium to give the μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetraalkyldigallanes. These were converted into the 1,3‐bis(trimethylsilyl)‐2‐alkyl‐2‐pyridine‐1,3,2‐diazagalla‐[3]ferrocenophanes, of which the ethyl derivative was characterized by X‐ray structural analysis. Treatment of gallium trichloride with N,N′‐dilithio‐1,1′‐bis(trimethylsilylamino)ferrocene affords μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetrachlorodigallane along with bis(trimethylsilyl)‐2,2‐dichloro‐1‐aza‐3‐azonia‐2‐gallata‐[3]ferrocenophane as a side product, and both were structurally characterized by X‐ray analysis. The solution‐state structures of the new gallium compounds and aspects of their molecular dynamics in solution were studied by NMR spectroscopy (¹H, ¹³C, ²⁹Si NMR).