Coordination chemistry of fluorine in fluorocarbons

FLUO 2

Herbert Plenio, plenio@tu-darmstadt.de, Dept. of Chemistry, Darmstadt Institute of Technology, Petersenstr. 18, 64287 Darmstadt, Germany
It is still a matter of debate, whether CF-units can take part in hydrogen bonding. On the other hand, there is strong evidence that covalently bonded fluorine is able to act as a donor atom towards metal cations in the solid state as well as in solution. The present contribution wants to summarize the experimental and theoretical results in this field. The first and basic question is: Can covalently bonded fluorine (eg. in CF-units) act as a donor towards metal ions in the solid state and in solution and is it possible to synthesize metal complexes in which coordination by covalently bonded fluorine contributes significantly to complex stability? For this purpose we have synthesized a number of partially fluorinated macrocycles as well as the respective metal complexes and investigated possible metal ion fluorine contacts by NMR-spectroscopy, X-ray crystal structure analysis, stability constant determination (potentiometry, calorimetry) and DFT-studies.