Trifluoroethyl group ethers

The common 2,2,2-trifluorocthyl group was discussed in Chapter 5. Less commonly encountered is the 1,1,2-trifluoroethyl group, the ether... 

Condensation of sodium phenoxide witli 2,2,2-trifluoroethyl iodide gives a product of direct substitution in a low yield, several other ethers are formed by eliminatton-addition reactions [7] Use of mesylate as a leaving group and hex amethyl phosphoramide (HMPA) as a solvent increases the yield of the substitution [S] Even chlorine can be replaced when the condensation is performed with potassium fluoride and acetic acid at a high temperature [9] (equations 6-8)... 

Regarding proton spectra, as was the case with 2,2,2-trifluoroethyl chloride (Scheme 5.7), the chemical shifts of the CH2 protons of 2,2,2-tri-fluoroethanol and of 2,2,2-trifluoroethyl ethers are more affected by the OH or ether substituents than they are by the CF3 group. 

Leenheer et al. (1983) have also prepared the trifluoroethyl ethers of humic materials by reaction of a sample suspended in methylene chloride with trifluorodiazoethane. Proton, C, and NMR of this derivative provide information on the concentration of aliphatic hydroxyl groups. 

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