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

Participants

Reaction Steps

O-Benzotriazol-1-yl-N,N,N′N′-tetramethyluronium tetrafluoroborate (1.09 g, 3.4 mmol) and diisopropylethylamine (0.98 g, 5.7 mmol) were added sequentially to a stirred solution of N-[2-fluoro-5-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)phenyl]-2-methylsuccinamic acid (1 g, 2.6 mmol) in dimethylacetamide (5 ml), the mixture was stirred at ambient temperature for 15 minutes, then it was poured onto water (50 ml) and allowed to stand at ambient temperature for 20 hours. The resulting solid was collected by filtration, washed with hexane (20 ml) and dried in vacuo to give 1-[2-fluoro-5-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)phenyl]-3-methylpyrrolidine-2,5-dione (0.654 g) as a beige solid, m.pt. 171–172° C.; 250 MHz 1H-nmr (d6-DMSO) δ (ppm): 1.4 (d, 3H) (CH3), 2.6–2.7 (m, obscured by DMSO signal, 1H) (—CHMe-), 3.05–3.3 (m, 2H) (—CH2CHMe-), 4.5 (s, 2H) (ArCH2—), 7.3–7.55 (m, 2H) (2×ArH), 7.6–7.7 (m, 1H) (ArH), 7.9–8.2 (m, 3H) (3×ArH), 8.4 (d, 1H) (ArH), 12.8 (s, 1H) (CONH); m/z (M+H)+ 366, 98% purity.

Provenance & Evidence