Ethyl Acetate → 3,4,6-Trifluorophthalic anhydride

Participants

Reaction Conditions

Reaction Steps

5.5 g (25 mmol) of tetrafluorophthalic anhydride were added under nitrogen to a solution of 3.58 g (89.5 mmol) of sodium hydroxide in 30 g of water. The mixture was then heated at 100° C., and 6.54 g (0.1 mol) of zinc dust were added. The course of the reaction was monitored by GC(TLC), and the reaction was complete after 12 hours. 50 ml portions of water and ethyl acetate were added and the voluminous solids were filtered off with suction and washed four times with 50 ml portions of water. The colorless filtrate was brought to a pH of 1 and extracted using ethyl acetate. Drying of the organic phases over MgSO4, filtration and removal of the solvent in vacuo gave 4.72 g (22.2 mmol; 89%) of colorless powder which could be identified as 3,4,6-trifluorophthalic acid (melting point 156°-160° C). Azeotropic dehydration in boiling xylene gave 3,4,6-trifluorophthalic anhydride.

Provenance & Evidence