Adducts of (C6F5)3B with Selected Nitrogen

The Lewis acid (C₆F₅)₃B was reacted with ICN, NH₂CN, C₃N₃X₃ (X = H, Cl, F). The resulting Lewis acid base adducts ( 1—5 ) were fully characterized by analytic and spectroscopic methods. Additionally, the structures of the adducts 1—4 were determined by single crystal X‐ray analyses. It has been qualitatively shown, that a high field shift of the ¹¹B as well as the ¹⁹F NMR resonances of the o‐F atoms of the C₆F₅‐substituents suggests a longer B—N distance.     

Polyfluorinated hexabenzyl hexaazaisowurtzitanes

A study of the reactivity of polyfluorobenzylamines towards the condensation with glyoxal is described. Selected fluorobenzylamines, 3,4-difluorobenzylamine, 3,4,5-trifluorobenzylamine and pentafluorobenzylamine react to give the corresponding hexabenzyl substituted hexaazaisowurtzitanes, (3,4-C₆F₂H₃CH₂)₆(NCH)₆ (1), (3,4,5-C₆F₃H₂CH₂)₆(NCH)₆ (2) and (C₆F₅CH₂)₆(NCH)₆ (3). An unusual by-product is formed and could be isolated from the condensation with pentafluorobenzylamine. The exact constitution, a novel mixed O/N containing isowurtzitane, (C₆F₅CH₂)₅(NCH)₅OCH (4), was elucidated by crystal structure determination. Furthermore, the crystal structures of 1 and 3 were determined.     

Tellurium(IV) Fluorides and Azides containing the Nitrogen Donor Substituent R = 2‐Me2NCH2C6H4; Crystal Structure of RTeF3 and of an Unusual Tellurium(VI) Fluoride Salt

The tellurenyl fluoride, 2‐Me₂NCH₂C₆H₄TeF, was obtained from reaction of the tellurenyl iodide RTeI with AgF. The compound was unambiguously identified by ¹⁹F and ¹²⁵Te NMR spectroscopy. The decomposition under disproportionation leads to the tellurium(IV) trifluoride, 2‐Me₂NCH₂C₆H₄TeF₃ and the ditelluride RTeTeR. The fluorination of the ditelluride, (2‐Me₂NCH₂C₆H₄Te)₂, with XeF₂ results in pure RTeF₃. The molecular structure of 2‐Me₂NCH₂C₆H₄TeF₃, the second structural characterized tellurium(IV) trifluoride, has been determined. Furthermore the syntheses of the new tellurium(IV) difluoride, (2‐Me₂NCH₂C₆H₄)₂TeF₂, and corresponding tellurium(IV) diazide, (2‐Me₂NCH₂C₆H₄)₂Te(N₃)₂ as well as the tellurium(IV) triazide, 2‐Me₂NCH₂C₆H₄Te(N₃)₃, and their characterization by spectroscopic methods were reported. During these investigations a rather interesting tellurium(VI) species was formed and the molecular structure of a subsequent product, [(2‐Me₂NHCH₂C₆H₄)₂TeF₃O]₂(SiF₆), was elucidated. Theoretical investigations for the compounds containing the stabilizing 2‐dimethylaminomethylphenyl substituent are illustrated.     

Highly energetic tetraazidoborate anion and boron triazide adducts

The first crystal structures of the highly energetic tetraazidoborate anion and boron triazide adducts with quinoline and pyrazine as well as of tetramethylpiperidinium azide have been determined. Synthesis procedures and thorough characterization by spectroscopic methods of these hazardous materials are given. Quantum chemical calculations were carried out for B(N(3))(4)(-), B(N(3))(3), C(5)H(5)N.B(N(3))(3), (N(3))(3)B.NC(4)H(4)N.B(N(3))(3), and the hypothetical C(3)H(3)N(3).[B(N(3))(3)](3) at HF, MP2, and B3-LYP levels of theory. The structure of tetraazidoborate was optimized to S(4) symmetry and confirmed the results obtained from the X-ray diffraction analysis. The dissociation enthalpies for the pyridine (model for quinoline) as well as for the pyrazine adduct were calculated. For pyridine-boron triazide a value of 10.0 kcal mol(-1) (for pyrazine-bis(boron triazide) an average of 2.35 kcal mol(-1) per BN unit) was obtained.     

[Hg8(μ‐n‐C3H7Te)12(μ‐Br)Br3] — Synthesis and Structure

The novel mercury‐tellurium cluster [Hg₈(μ‐n‐C₃H₇Te)₁₂(μ₂‐Br)Br₃] is formed during the reaction of HgBr₂ and (n‐C₃H₇Te)₂Hg in DMSO. Its crystal structure has been elucidated showing [Hg₈(μ‐n‐C₃H₇Te)₁₂(μ₂‐Br)]³⁺ units with a bromine‐centered distorted Hg₈ cube. The mercury atoms are bridged by n‐C₃H₇Te^— ligands and the resulting clusters are linked to a three‐dimensional network by bromine atoms. The close packing of the cluster is mainly determined by the flexible n‐propyl residues of the telluride building blocks.