Triethylamine → 3-bromo-1-phenylpyrrole-2,5-dione

Participants

Reaction Steps

To N-phenylmaleimide (2 g, 11.50 mmol) in chloroform (15 mL) was added bromine (0.65 mL, 12.70 mmol) dropwise in chloroform (5 mL). The reaction mixture was refluxed for 1 hour, and then allowed to cool to room temperature. The precipitate was filtered off and washed with chloroform (50 mL). This solid (2.70 g, 8.10 mmol) was dissolved in tetrahydrofuran (50 mL) and to this was added dropwise dropwise a solution of triethylamine (1.2 mL, 8.9 mmol) in tetrahydrofuran (10 mL) at 0° C. and the mixture was stirred for 2 hours. The mixture was allowed to warm to room temperature and solvent removed in vacuo. The residue was dissolved in ethyl acetate and washed with H2O (50 mL) brine (50 mL) and dried (Na2SO4). Solvent was removed in vacuo to afford the desired compound as a pale yellow solid (1.80 g, 7.14 mmol) in 62% yield. Data matched literature: Sahoo et al., Synthesis, 2003, 346

Provenance & Evidence