Fluorinated alkyl cobaloximes

Finally, we note as a general observation for the fluorinated alkyl cobaloximes that i F NMR resonances for the a-F atoms generally are broadened due to incomplete averaging of coupling to the quadrupolar 59Co (I = 7/2) nucleus. This broadening is evident for the CF=CF2 complexes as well, where the F atom on the carbon atom attached to cobalt is severely broadened and the F atom trans to the cobalt is slightly broadened (25),... 

Synthetic methods have been devised that lead to moderate to good yields of a-fluorinated alkyl cobaloximes. NMR studies and structural comparisons to the nonfluorinated analogs suggest that there is a significant ionic character in the bonding of the fluorinated alkyl ligands to the cobalt center. 

The synthesis and characterization of cobaloximes that have fluorine-containing alkyl ligands, especially those with fluorine substituents at the carbon atom (a-C) attached to the cobalt ion, are the topic of this report. As noted above, the cobaloximes have been intensely examined spectroscopically and numerous high quality solid-state structural investigations have been previously accomplished (7-5). We have been interested in exploiting these properties of the cobaloxime system in order to assess the effect of fluorine substitution on spectroscopic and structural parameters of this class of compounds. 

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