Hypofluorous acid, trifluoromethyl ester → 4-Chloro-α-fluorobenzeneacetic acid

Participants

Reaction Steps

A solution of 29.92 g (0.095 mol) of the aforesaid β,β-bis(trimethylsiloxy)p-chlorostyrene in 300 ml of CFCl3 was cooled to -70° C. and 9.88 g (0.095 mol) of trifluoromethyl hypofluorite were passed into the solution over a period of 2 hours. The mixture was allowed to warm to room temperature and evaporated to dryness under reduced pressure. The resultant white solid residue was stirred with 10 ml of water for approximately 10 minutes. The solids were recrystallized from 1 l of hexane to give 9.38 g (53% yield) of p-chlorophenylfluoroacetic acid as shiny white crystals, mp 66°-68° C.; 1H NMR (CDCl3) δ5.75 (d, J≅47 Hz, 1H), δ7.35 ppm (s, 4H), δ10.95 (s, 1H); 19F NMR (CDCl3) δ-182.60 (d, J≅47 Hz).

Provenance & Evidence