Trifluoroacetic acid → 5-chloro-2-methyl-3H,4H-pyrrolo[2,1-f][1,2,4]triazin-4-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 1-amino-3-chloro-1H-pyrrole-2-carboxylic acid methyl ester, hydrochloride salt (11.0 g, 52.1 mmol) and trifluoroacetic acid (6.0 mL, 77.9 mmol) in acetonitrile (230 mL) was heated at 85° C. overnight. The reaction mixture was concentrated and treated with fresh acetonitrile (200 mL) and triethylamine (22.0 mL, 157.8 mmol). The reaction mixture was heated at 85° C. overnight and concentrated to small volume and diluted with water (100 mL). The mixture was then stirred at rt for 20 min. The precipitate was collected, washed with water and dried to give the title compound as a brown solid (7.67 g, 80%): 1H NMR (CD3OD): δ 7.28 (s, 1H), 6.42 (s, 1H), 2.20 (s, 3H); MS (ESI+) 184.02, 186.10 (M++H).

Provenance & Evidence