Direct fluorination of γ-butyrolactone

γ-Butyrolactone was fluorinated by molecular fluorine to obtain its mono-fluorinated derivatives for possible lithium battery electrolyte application. The reaction was carried out at 30°C by introducing 20% F2/N2 gas into γ-butyrolactone without solvent. Major products were β-fluoro-γ-butyrolactone and γ-fluoro-γ-butyrolactone, which cannot be obtained by conventional organic synthesis. Selectivity to γ-isomer was enhanced by the addition of NaF as a HF scavenger.