Umsetzungen von Δ-triazolinen und von ringketon-anilen mit isocyanaten und isothiocyanaten

Δ²-Triazolines, derived from cyclopentene and aryl azides, react with isocyanates and isothiocyanates giving 1-arylamino-2-carboxamido- and 1-arylamino-2-thiocarboxamido-cyclopentenes respectively. Cyclopentanone anils, which are formed from the triazolines by thermal loss of nitrogen, are intermediates. In contrast, the Δ²-triazoline from norbornene and phenyl azide undergoes induced loss of nitrogen on treatment with phenylisocyanate. The product, a 1:1 adduct less N₂, has been investigated chemically and spectroscopically; the final structural elucidation however requires further experiments.     

Einkristallzüchtung und Strukturverfeinerung von RbAu und CsAu

Single-Crystal Growth and Structure Refinement of RbAu and CsAu Single-crystals of RbAu and CsAu were obtained by the reaction of the alkalimetal azides with gold-powder at 400°C. The structures were determined from X-ray single-crystal diffraktometer data: space group Pm3m, Z = 1; RbAu, a = 4.098(1) Å, R/R_w(w = 1) = 0.011/0.011, N(F_o²) ≥ 3σ(F_o²) = 41 and N(var.) = 4; CsAu, a = 4.258(1) Å, R/R_w(w = 1) = 0.009/0.010, N(F_o²) ≥ 3σ(F_o²) = 34 and N(var.) = 4. Both compounds crystallize in the completely ordered CsCl-type with neglible deviations from the ideal 1:1-composition.     

Synthese und Strukturaufklärung von Merucathinon und Synthese von Cathinon. Inhaltsstoffe von Catha edulis FORSK

Synthesis and Structure Elucidation of Merucathinone and Synthesis of Cathinone. Constituents of Catha edulis FORSK . Starting from L-alanine, two constituents of Catha edulis FORSK ., (S)-4-amino-1-phenylpent-1-en-3-on ((S)- 3 ; merucathinone) and (S)-2-amino-1-phenylpropan-1-on ((S)- 1 ; cathinone) were synthesized.     

Bildung und Eigenschaften von Aoylphosphinen. III. Molekül- und KristallStruktur von Dipivaloylphosphin

Syntheses and Properties of Acylphosphines. III. Molecular and Crystal Structure of Dipivaloylphosphine In the reaction of tris(trimethylsilyl)phosphine with pivaloyl chloride two Si? P bonds are cleaved and dipivaloyltrimethylsilylphosphine is formed. Reaction with methanol yields dipivaloylphosphine. N.m.r. investigations show a tautomeric equilibrium between keto and enol form as in β-diketones. The substance crystallizes in the orthorhombic space group Pmmn with molecules in two crystallographically different sites [cell parameters: a = 14.04(1), b = 13.82(1), c = 6.28(2) Å]. An X-ray structure determination (R = 5.0%) proves the existence of the enol form in the solid, in that (1.) the molecular symmetry is mm 2(C_2v), (2.) P? C bonds are shortened and C? O bonds are elongated, and (3.) we find a symmetric hydrogen bridge with a very short O? O distance. Bond lengths and angles are compared with those of other β-diketones. The packing of molecules is studied in detail.     

Einkristallzüchtung und Strukturanalyse von Trikaliumorthonitrat

Crystal Growth and X-ray Structure Determination of the Tripotassiumorthonitrate The title compound has been characterized by single crystal x-ray diffraction: 1126 diffractometer data, space group Pnma, a=10.921(1), b=7.952(1), c=5.667(1) Å, Z=4, R_w =0.024. The distance N? O in the tetrahedron oxoanion (1.398 Å) is only little, but significantly larger than in Na₃NO₄. More significant are the shifts of the absorption frequencies in the vibrational spectra to lower wave numbers (e.g. 24 cm^?1 for the symmetric stretching mode). The anions are arranged similar to a cubic closest packing with potassium placed on all tetrahedral and octahedral sites.     

Synthese und Charakterisierung von InIII–SnII‐Halogenido‐Alkoxiden und von Indiumtri‐tert‐butoxid

Synthesis and Characterization of In^III–Sn^II‐Halogenido‐Alkoxides and of Indiumtri‐ tert ‐butoxide Through sodium halide elimination between Indium(III) halides and sodium‐tri‐tert‐butoxistannate(II) or sodium‐tri‐tert‐butoxigermanate(II) the three new heterometallic and heteroleptic alkoxo compounds THF · Cl₂In(OtBu)₃Sn ( 1 ), THF · Br₂In(OtBu)₃Sn ( 2 ), and THF · Cl₂In‐ (OtBu)₃Ge ( 3 ), have been synthesized. The molecular structures of 1 and 2 in the solid state follow from single crystal X‐ray structure determinations while structural changes in solution may be derived from temperature dependant NMR spectroscopy. The crystal structures of compounds 1 and 2 are despite different halide atoms isostructural. Both crystallize in the ortho‐rhombic crystal system in space group Pbca with eight molecules per unit cell. The heavy atoms occupy the apical positions of empty trigonal bipyramids of almost point symmetry C_s(m) and are connected through oxygen atoms occupying the equatorial positions. The indium atoms in both compounds are in the centers of distorted octahedra from 4 oxygen and 2 halogen atoms whereas the tin atoms are coordinated by three oxygen atoms in a trigonal pyramidal fashion. Although the coordinative bonding of THF to indium leads to an asymmetry of the molecule the NMR spectra in solution are simple showing a more complex pattern at lower temperatures. Tri(tert‐butoxi)indium [In(OtBu)₃]₂ ( 4 ), is obtained through alcoholysis of In(N(Si(CH₃)₃)₂)₃ using tert‐butanol in toluene and is crystallized from hexane. The X‐ray structure determination of 4 seems to be the first one of a homoleptic and homometallic indiumalkoxide. Compound 4 crystallizes in the monoclinic crystal system in a dimeric form with eight molecules in the unit cell of space group C2/c. The dimeric units have C₂ symmetry and an almost planar In₂O₂ ring which originates from oxygen bridging of the monomers. Through this mutual Lewis acid base interaction the indium atoms get four oxygen ligands in a distorted tetrahedral environment.     

Kristall- und Molekülstruktur von Tetra-n-butylammonium-N-methyl-N-thioformyldithiocarbamat

Crystal and Molecular Structure of Tetra-n-butylammonium N-Methyl-N-Thioformyl Dithiocarbamate [N(n-C₄H₉)₄][S₂C? N(CH₃)? CS? H] crystallizes in the triclinic space group P1 (Z = 2) with cell dimensions (?45°C) a = 9.185(2) Å, b = 10.263(3) Å, c = 13.301(3) Å, α = 101.73(2)°, ß = 99.59(2)°, γ 100.57(2)°. The crystal structure was solved by means of direct methods and refined to a conventional reliability index R = 0.066 (R_ω = 0.070). 5945 independent intensities being measured.     

Organoblei- und Organozinnderivate von Mercaptoaminosäuren und Cysteamin

Organolead and Organotin Derivatives of Mercaptoaminoacids and Cysteamin Reaction of tri- and diorganolead and -tin hydroxides and oxides with mercaptoaminoacids and cysteamine in CHCl₃ or CHCl₃/H₂O allows the gentle preparation of the above compounds. The bonding between M and ligand indicated in the formula of the compounds, mainly the preferred bonding of M to S follows from vibrational spectra; proposals regarding the structure are made using spectral data. Ph₃SnOH and penicillamine react to give monomeric Ph₃SnSCMe₂CH(NH₂)COOSnPh₃.