Fluorine-containing ligands

Figure 36 Some scC02-soluble fluorine containing ligands.

The presence of inter- and intra-molecular C-F---H contacts is mostly supported by crystallographic data. Often a F---H distance shorter than the sum of the F and H van der Waals radii (-2.65 A) is used as evidence for a C-F---H interaction [129]. A review of the PDB in 2004 using this distance criterion as well as directional constraints found that ""...there is an 18% chance that a generic PDB entry with a co-crystallized fluorine-containing ligand presents a hydrogen-bond occurring al the fluorine and that ""10% of the overall amount of fluorine atoms from the PDB... 

Introduction of Fluorine-Containing Ligands Via Highly Fluorinated Olefins. It is known that [pyCoi(DH)2] will substitute readily the halogen of vinyl and styryl halides (26). On the other hand, [pyCoI(DH)2]- reacts with CH2=CHZ... 

We are continuing to study the synthesis, structure, and reactivity of highly electrophilic early transition metal complexes. Fluorine containing ligands and counterions are playing an increasingly important role in these studies because of the low reactivity associated wifli the strong carbon-fluorine bonds. 

Several F NMR studies have been reported on ligand exchange reactions of metal complexes (i.e. the Al(Ttfac)3-Al(bzac)3 system) and also on relative polarity and reactivity of N-H, N-Hg and N-Au bonds in intermolecular exchange reactions of fluorine-containing ligands (for example, 2-(4-fluoro-phenyl) benzimidazole) and their PhHg and Ph3PAu derivatives. 

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