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This dissertation offers at least four new contributions to chemical science: (1) A new method of generation iodofluorides and organoiodofluorides, in which a simple, general and industrial applicable route to I-F compound was developed. This method is suitable for the synthesis of IF5, organoiodine(III) fluorides, and -(V)fluorides. The convenient method is characterised by an oxygen-fluorine substitution process using anhydrous HF (aHF) or aqueous HF in a two phase system. (2) The first synthesis of perfluoroalkenyl(aryl)iodonium tetrafluoroborate salts is reported. The salts result from the reaction of (difluoroiodo)arenes (ArIF2) generally with organodifluorboranes to yield the corresponding organo(aryl)iodonium tetrafluoroborates in good yields and high purity. The iodonium salts were investigated spectroscopically and structurally. (3) Key reactivities of monofluoro(difluoroiodo)benzenes are investigated. The reactions of (difluoroiodo)arenes (Ar = o-, m-, p-C6H4F) with n [N(CH3)4]F (n = 0.5, 1, 2, 3), CsF (n = 1, 2), 2,2´-bipyridine, and different kind of alcohols (CH3OH, CH3CH2OH and CF3CH2OH) and protonic acids (CF3CO2H, HF) were examined. The solid structure of ArIF2 (Ar = o-, p-C6H4F) was investigated which show strong intermolecular contacts between the positively charged iodine centre and negatively charged fluorine atoms of the IF2 group of neighbour molecules. Zigzag arrangements result in case of the para and ortho isomers. (4) Introduction concerning the reactivity of perfluoroalkenyl(aryl)iodonium tetrafluoroborate salts were performed. The reactions of perfluorovinyl(aryl)iodonium tetrafluoroborate salts with [N(CH3)4]F in dichloromethane show that the metathesis of the tetrafluoroborate anion by fluoride was accompanied by the spontaneous decomposition even at low temperature. The reaction of [trans-CF3CF=CF(aryl)I][BF4] with weak but oxidisable Lewis bases such as (p-C6H4F)3As or (p-C6H4F)3P emphasise the preparative potential of perfluoroalkenyl-(aryl)iodonium salts to enable the electrophilic alkenylation of nucleophiles. In the present case [trans-CF3CF=CF(p-C6H4F)3As][BF4] and [trans-CF3CF=CF(p-C6H4F)3P][BF4] were formed in a mixture of by-products. In the crystal structure of the alkenyl(aryl)iodonium tetrafluoroborate salt a pronounced cation anion interaction was found which lead to a three-dimensional network.

Duisburg, Essen, Univ., Diss., 2003 The preparation and characterization of new molecular covalent compounds with a xenon-carbon bond is described within the framework of this thesis. Pentafluorophenylxenon(II) fluoride and 2,4,6-trifluorophenylxenon(II) fluoride are prepared by metathesis of arylxenon(II)salts and tetramethylammonium fluoride in dichloromethane at -78 °C. These asymmetric hypervalent molecules possess a weak and elongated xenon-fluorine bond when compared to xenon difluoride. The high polarity of the Xe-F bond enables the fluorine abstraction even with weak Lewis acids. The fluorine-ligand in arylxenon(II) fluorides can easily substituted, e.g. during the reaction with diarylcadmium the corresponding diarylxenon(II) compounds are formed. Using that approach bis(pentafluorophenyl)xenon(II), bis(2,4,6-trifluorophenyl)xenon(II) and the asymmetric compound (pentafluorophenyl)2,4,6-trifluorophenylxenon(II) are prepared and characterized by multinuclear NMR spectroscopy. Further the preparation of bis(pentafluorophenyl)xenon(II) starting from pentafluorophenylxenon(II) fluoride or xenon difluoride and pentafluorophenylsilanes with different Lewis acidities is investigated. This procedure was also extended to perfluoroalkenyl or perfluoroalkyl ligands. Pentafluorophenylxenon(II) chloride and 2,4,6-trifluorophenylxeon(II) chloride are prepared by conversion of the corresponding Arylxenon(II) fluorides with trimethylsilyl chloride while Pentafluorophenylxenon(II) cyanide is generated using trimethylsilyl cyanide as a substrate. The reactions with trimethylesilyl thiocyanide and -bromide did not yield pentafluorphenylxenon(II) thiocyanide or bromide respectively. The NMR spectra of the new arylxenon(II) compounds are discussed as well as compared with NMR data from existing arylxenon(II) compounds. The interpretation is supported by ab initio calculations on RHF level.