Ethylenediamine → 7-bromo-10a-(4-chlorophenyl)-2,3,10,10a-tetrahydro-1H,5H-imidazo[1,2-a]pyrrolo[1,2-d]pyrazin-5-one

Participants

Reaction Steps

To a solution of crude 4-bromo-1-[2-(4-chlorophenyl)-2-oxoethyl]-1H-pyrrole-2-carboxylic acid (100 mg, 0.29 mmol) dissolved in a mixture of xylenes (10 mL) and ethanol (3 mL) was added ethane-1,2-diamine (100 μL, 1.5 mmol). The reaction mixture was heated at reflux. After 90 minutes (monitored by LCMS) the mixture was concentrated in vacuo and the resultant residue purified flash chromatography (Biotage SP4, 40 g cartridge, 0-5% MeOH gradient in CH2Cl2) to give 7-bromo-10a-(4-chlorophenyl)-2,3,10,10a-tetrahydro-1H,5H-imidazo[1,2-a]pyrrolo[1,2-d]pyrazin-5-one as a light yellow solid (73 mg, yield: 68%). 1H NMR (400 MHz, d6-acetone): δ 2.74-2.82 (m, 1H), 3.30-3.38 (m, 1H), 3.44 (ddd, 1H, J 7.7, 3.4, 1.3 Hz), 3.67-3.75 (m, 1H), 4.39 (d, 1H, J 12.5 Hz), 4.69 (d, 1H, J 12.5 Hz), 6.68 (d, 1H, 1.8 Hz), 6.79 (d, 1H, J 1.7 Hz), 7.32-7.40 (m, 4H).

Provenance & Evidence