Phthalic Anhydride → 2-(2-(2-Oxoindolin-3-yl)ethyl)isoindoline-1,3-dione

Participants

Reaction Steps

A mixture of 3-(2-aminoethyl)indolin-2-one hydrochloride (3.20 g, 15.06 mmol), phthalic anhydride (3.34 g, 22.59 mmol) and TEA (4.56 g, 45.18 mmol) in toluene/NMP (20 mL/10 mL). The mixture was heated under reflux for 3 h. The reaction mixture was concentrated and the resulting mixture was washed with saturated aqueous ammonium chloride and brine. The separated organic layer was dried over anhydrous sodium sulfate and filtered. Concentration under vacuum gave the crude product, which was purified by silica gel column chromatography (30% ethyl acetate in petroleum ether) to afford the title compound (2.60 g, 8.50 mmol, 56% yield) as a brown solid. MS (ESI) m/z 307.2 [M+H]+.

Provenance & Evidence