Phthalimide → 2-(3-Oxocyclopentyl)-1H-isoindole-1,3(2H)-dione

Participants

Reaction Steps

Mix cyclopentenone (100 g, 1.2 mol) and phthalimide (170 g, 1.2 mmol) in MeOH (900 mL) and stir for 18 h at ambient temperature. Stir vigorously with a mechanical stirrer and add 2 M aqueous Na2CO3 (80 mL). After approximately 2 h, a thick white precipitate will form. Stir at room temperature for 48 h. Collect the white solid by vacuum filtration and rinse with methanol. Suspend the solid in water (300 mL) and stir for 3 h. Collect the solid and dry in a vacuum oven at 40° C. overnight to give 195 g (71%) of the title compound as a white solid. 1H NMR (DMSO-d6) δ 7.85-7.77 (m, 4H), 4.90 (m, 1H), 2.67 (ddd, 1H, J=18.5, 6.2, 1.3 Hz), 2.54 (dd, 1H, J=18.5, 9.2 Hz), 2.45 (m, 1H), 2.32-2.21 (m, 3H); MS (m/z): 230 (M+1, weak).

Provenance & Evidence