Nitric Acid → 2,3,4-Trifluoro-5-nitrobenzoic acid

Participants

Reaction Steps

A 3 liter three neck round bottom flask is charged with 125 mL H2SO4. Fuming nitric acid is added (8.4 mL, 199 mmol) and the mixture gently stirred. 2,3,4-Trifluorobenzoic acid 1 (25 g, 142 mmol) is added in 5g portions over 90 minutes. The dark brownish yellow solution is stirred for 60 minutes at which time the reaction is complete. The reaction mixture is poured into 1 liter of an ice water mixture and extracted with diethyl ether (3×600 mL). The combined organic extracts are dried (MgSO4) and concentrated under reduced pressure to give a yellow solid. The solid is suspended in hexanes and stirred for 30 minutes after which time it is filtered to give 29 g (92%) of clean desired product as an off-yellow solid: MS APCI (−) m/z 220 (M−1) detected.

Provenance & Evidence