Procedure

1. To a solution of isatin (500 mg, 3.39 mmol) in dry DMF (10 mL) was added powdered calcium hydride (472 mg, 11.21 mmol), and the mixture was stirred with gentle warming (40–50°C) for half an hour.
2. The allylating agent (16.99 mmol) was added to the reaction mixture at room temperature and stirred for 4–5 hours.
3. The reaction mixture was then poured slowly into a neutralized solution of brine.
4. The organic layer was extracted using ethyl acetate several times.
5. Evaporation of the solvent left a residue, which was then subjected to chromatography on a silica gel column using an 80:20 hexane:ethyl acetate solvent mixture to afford the N-allyl derivative of isatin.