Bisphosphazen-Protonenschwämme und Metall-Perfluoranilide: Liganddesign für Brønsted-Superbasen und Lewis-Supersäuren

The first part of this dissertation treats the fundamental principles of BRØNSTED superbasicity. It has been successfully demonstrated in the SUNDERMEYER group that the combination of SCHWESINGER's phosphazene bases with ALDER's concept of proton sponges with two interacting proton acceptor functionalities leads to neutral organic superbases with high pKBH+ values in the range of 30 on the acetonitrile scale. In the first part of this thesis, the potential of the STAUDINGER and the KIRSANOV reaction for the preparation of such bisphosphazene proton sponges was investigated. It was studied how new structure motives like the substitution of the amino substituents in known bisphosphazenes for alkyl groups or the insertion of another PN unit affects the basicity of the proton sponges. A focus was on the structural characterization of the bisphosphazenes as free bases as well as in their protonated forms. Furthermore, the hybrid superbases were studied concerning their nucleophilic properties, kinetic basicity and coordination chemistry in neutral and cationic group 12 and 13 metal alkyl complexes. The experience with chelating phosphazene bases was also applied to the preparation of chelating superbases. The second part of this work is concerned with the principles of strong LEWIS acids with weakly coordinating amido ligands. In this context, NH-acidic amines and amides with two different perfluorinated strongly electron-withdrawing substituents were considered. New representatives of this compound class were prepared and characterized with respect to their coordination chemistry and their potential to generate highly LEWIS acidic group 13 metal complexes. The latter were extensively studied with reference to their LEWIS acidic properties.