Potassium Nitrate → 2-Nitro-5-(trifluoromethoxy)benzoic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-trifluoromethoxybenzoic acid (49.0 g, 0.24 mol) in sulfuric acid (500 mL) at less than 0° C. (ice-MeOH bath) was added a solution of potassium nitrate (31.3 g, 0.31 mol) in sulfuric acid (200 mL) over 20 minutes. The resulting solution was stirred at 0° C. for 2 hours, then warmed to room temperature and stirred for 18 hours. The reaction was poured into ice and the resulting acidic solution was extracted with EtOAc (5×). The combined organics were washed with H2O (1×), brine (2×), H2O (1×) and brine (1×), dried (Na2SO4), filtered and concentrated in vacuo to give the crude sub-title compound (65.7 g) as a solid contaminated with HOAc. The crude sub-title compound was dissolved in EtOAc and toluene and concentrated in vacuo to give a HOAc free solid (58.4 g, 97%) that was used in the next step without further purification.

Provenance & Evidence