17O-NMR study of polyfluorinated alcohols and ethers

Abstract

δ 17O values are reported for 16 polyfluorinated alcohols and ethers. The 17O-nuclear shielding increases with fluorine substituents in γ-position and it decreases (much more than expected by comparison with δ 13C-values) with fluorine substituents in β- position. The π-interactions between oxygen and a vinyl or a phenyl group (α,β -unsaturation) are greatly reduced if a CHF 2CF 2 group is attached to the oxygen. Conclusions from δ 17O- data are supported by 13C-, 11B- and 29Si-chemical shifts.