Synthese und Charakterisierung von nichtklassischen Polyinterhalogeniden basierend auf Brommonochlorid

In Situ Synthesis and Applications for Polyinterhalides Based on BrCl

The use of neat BrCl in organic and inorganic chemistry is limited due to its gaseous aggregate state and especially its decomposition into Cl2 and Br2 . The stabilization of BrCl in form of reactive ionic liquids via a novel in situ synthesis route shifts this equilibrium drastically to the BrCl side, which leads to safer and easier-to-handle interhalogenation reagents. Furthermore, the crystalline derivatives of the hitherto unknown [Cl(BrCl)2 ]- and [Cl(BrCl)4 ]- anions were synthesized and characterized by single-crystal X-ray diffraction (XRD), Raman and IR spectroscopy, as well as quantum chemical calculations.

Synthesis and Characterization of Poly(hydrogen halide) Halogenates (-I)

Herein, we report the synthesis and characterization of a variety of novel poly(hydrogen halide) halogenates (-I). The bifluoride ion, which is known to have the highest hydrogen bond energy of ≈160 kJ mol-1 , is the most famous among many examples of [X(HX)n ]- anions (X=F, Cl) known in the literature. In contrast, little is known about poly(hydrogen halide) halogenates containing two different halogens, ([X(HY)n ]- ). In this work we present the synthesis of anions of the type [X(HY)n ]- (X=Br, I, ClO4 ; Y=Cl, Br, CN) stabilized by the [PPh4 ]+ and [PPN]+ cation. The obtained compounds have been characterized by single-crystal X-ray diffraction, Raman spectroscopy and quantum-chemical calculations. In addition, the behavior of halide ions in hydrogen fluoride was investigated by using experimental and quantum-chemical methods in order to gain knowledge on the acidity of hydrogen halides in HF.

Improved Access to Organo-Soluble Di- and Tetrafluoridochlorate(I)/(III) Salts

A facile one-pot gram-scale synthesis of tetraalkylammonium tetrafluoridochlorate(III) [cat][ClF4 ] ([cat]=[NEt3 Me]+ , [NEt4 ]+ ) is described. An acetonitrile solution of the corresponding alkylammonium chloride salt is fluorinated with diluted fluorine at low temperatures. The reaction proceeds via the [ClF2 ]- anion which is structurally characterized for the first time. The potential application of [ClF4 ]- salts as fluorinating agents is evaluated by the reaction with diphenyl disulfide, Ph2 S2 , to pentafluorosulfanyl benzene, PhSF5 . The CN moieties in acetonitrile and [B(CN)4 ]- are transferred in CF3 groups. Exposure of carbon monoxide, CO, leads to the formation of carbonyl fluoride, COF2 , and elemental gold is dissolved under the formation of tetrafluoridoaurate [AuF4 ]- .

From Polyhalides to Polypseudohalides: Chemistry Based on Cyanogen Bromide

Pseudohalogens are defined as molecular entities that resemble the halogens in their chemistry. While our understanding of polyhalogen chemistry has increased over the last years, research on polypseudohalogen compounds is lacking. The pseudohalogen BrCN possesses a highly pronounced σ-hole at the bromine side of the molecule, inducing strong halogen bonding. This allows the synthesis and characterization of new polypseudohalogen anions, as shown by the single-crystal X-ray diffraction of [PNP][Br(BrCN)] and [PNP][Br(BrCN)₃ ]. Both the nearly linear anion [Br(BrCN)]^- and the distorted pyramidal anion [Br(BrCN)₃ ]^- were characterized by Raman spectroscopy and quantum-chemical calculations. The behavior of the polypseudohalogen compounds in solution and as room-temperature ionic liquids (RT-ILs) using the [NBu₄ ]⁺ cation was studied by ¹³ C and ¹⁵ N NMR spectroscopy. These types of ILs are capable of dissolving elemental gold and offer themselves as promising compounds in metal recycling.