Hydrochloric Acid → Phthalimidine

Participants

Reaction Steps

Phthalimide (1.47 g, 10 mmol) was added to a mixture of glacial acetic acid (15 mL), concentrated hydrochloric acid (7 mL), and tin powder (2.97 g). The slurry was heated at reflux for 2 h. After this time GC-MS indicated that the reaction was completed. The residual tin was removed by filtration and the majority of the acetic acid evaporated. The resulting creamy material was dissolved in dichloromethane (60 mL) and washed with water (10 mL) and saturated aqueous NaCl solution (15 mL). The resulting organic solution was dried over anhydrous MgSO4, filtered and concentrated. Silica gel column chromatography of the resulting material using ethyl acetate afforded 2,3-dihydro-isoindol-1-one (1 g, 75%) as an off-white solid. 1H NMR (300 MHz, CDCl3): δ (ppm) 4.48 (s, 2H), 6.98 (s, 1H), 7.42-7.61 (m, 3H), 7.88 (d, 1H).

Provenance & Evidence