p-Toluenesulfonic acid → 1-[3-bromo-5-(trifluoromethyl)phenyl]-2,5-dimethyl-1H-pyrrole

Participants

Reaction Steps

To a solution of 3-bromo-5-(trifluoromethyl)aniline (14.0 g, 58.3 mmol) in toluene (250 mL), was added hexane-2,5-dione (7.05 mL, 60.1 mmol) and pTSA (0.22 g, 1.20 mmol). The flask was fitted with a Dean Stark trap and reaction mixture was heated at reflux for 1 h. The mixture was allowed to cool to rt and concentrated. The residue was purified by filtration through a pad of silica to give 1-[3-bromo-5-(trifluoromethyl)phenyl]-2,5-dimethyl-1H-pyrrole as an orange solid (18.g g, 97.8%). 1H NMR (400 MHz, CDCl3) δ: 7.81 (s, 1H), 7.58 (s, 1H), 7.44 (s, 1H), 5.92 (s, 2H), and 2.05 (s, 6H).

Provenance & Evidence