Diisopropylethylamine → 1-[2-Fluoro-5-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)phenyl]-3-phenylpyrrolidine-2,5-dione

Participants

Reaction Steps

O-Benzotriazol-1-yl-N,N,N′N′-tetramethyluronium tetrafluoroborate (0.726 g, 2.26 mmol) and diisopropylethylamine (0.494 g, 3.8 mmol) were added sequentially at ambient temperature to a stirred solution of N-[2-fluoro-5-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)phenyl]-2-phenylsuccinamic acid (0.775 g, 1.7 mmol) in dimethylacetamide (4 ml), the mixture was stirred at ambient temperature for 65 hours, then it was added dropwise to ice-cold water (40 ml). The resulting solid was collected by filtration, washed with water (3 ml), then dried in vacuo. The crude product was dissolved in hot methanol (8 ml), the solution was filtered through a small plug of cotton wool, then the filtrate was added to water (30 ml). The resulting solid was collected by filtration and dried in vacuo to give 1-[2-fluoro-5-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)phenyl]-3-phenylpyrrolidine-2,5-dione (0.555 g) as an off-white solid, m.pt. 114–120° C.; 250 MHz 1H-nmr (CDCl3) δ (ppm): 2.8–3.0 (m, 1H) (—CHHCHPh), 3.2–3.4 (m, 1H) (—CHHCHPh), 4.1–4.3 (m, 1H+2H) (—CHPh- and ArCH2—), 7.0–7.4 (m, 8H) (8×ArH), 7.6–7.8 (m, 3H) (3×ArH), 8.4 (d, 1H) (ArH), 10.65 (s, 1H) (CONH); m/z (M+H)+. 428, 92.1% purity.

Provenance & Evidence