Phthalic Anhydride → 2-(5-methyl-1H-pyrazol-3-yl)-1H-isoindole-1,3(2H)-dione

Participants

Reaction Steps

In a 100 mL round-bottom flask a mixture of 5-methyl-1H-pyrazol-3-amine (Aldrich, 500 mg, 5.15 mmol) and phthalic anhydride (ALDRICH) (1.07 g, 7.21 mmol) in 1,4-dioxane (30 mL) was stirred at reflux for 25 hours. Reaction was allowed to reach room temperature and the formed precipitate was filtered and washed with EtOH to afford 589 mg of the title compound as a yellowish solid. Filtrate was evaporated to dryness and after washing the residue with EtOH, an additional batch of 331 mg was obtained (total yield: 79%). 1H NMR (300 MHz, DMSO-d6) δ ppm: 12.77 (br s, 1H), 7.87-7.98 (m, 4H), 6.09 (s, 1H), 2.28 (s, 3H). [ES+MS] m/z 228 (MH+).

Provenance & Evidence