Hydrochloric Acid → 4-(2,4,6-Trifluorobenzoyl)-1H-pyrrole-2-carboxylic acid

Participants

Reaction Steps

To a 120 mL dichloromethane solution of 2,4,6-trifluorobenzoyl chloride (4.3 g, 0.022 mol) was added AlCl3 (8.8 g, 0.066 mol) under N2 at room temperature. After stirring for 15 min, 1H-pyrrole-2-carboxylic acid (2.4 g, 0.022 mol) was added in small portions over a 10 min period. Stirring continued at room temperature for 1 hr, then the reaction mixture was treated with dropwise addition of ice-water (20 mL) and 1N HCl to adjust pH to 1. After stirring for another 30 min, the reaction mixture was extracted with AcOEt (3×30 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, filtered and concentrated to give the title compound (5.8 g, 97% yield). 1H-NMR (500 MHz, CDCl3): δ 12.48 (br.s, 1H), 7.48 (s, 1H), 7.28-7.38 (m, 2H), 6.83 (s, 1H).

Provenance & Evidence