Isatin → 7-Phenylisatin

Participants

Reaction Steps

This compound was prepared according to the procedure described by Lisowski et al. J. Org. Chem., 2000, 65, 4193. To a 1 L 3-necked round-bottomed flask fitted with a reflux condenser were added intermediate 6 (2.0 g, 7.33 mmol) and tetrakis[triphenylphosphine]palladium (0.424 g, 0.367 mmol), followed by 225 mL 1,2-dimethoxyethane. The atmosphere in the reaction vessel was made inert by opening to vacuum, then to a positive pressure of nitrogen (3×). Phenylboronic acid (Aldrich, 0.983 g, 8.06 mmol) and a solution of sodium bicarbonate (1.23 g, 14.7 mmol) in 225 mL water were added, and the evacuation/nitrogen procedure repeated one more time. The reaction mixture was then refluxed until t.l.c. (10% ethyl acetate in dichloromethane) showed complete disappearance of 7-iodoisatin (1-2 hours). After cooling to room temperature, the 1,2-dimethoxyethane was removed under reduced pressure. The residue was diluted with 1M aqueous hydrochloric acid and extracted into ethyl acetate (3×). The organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and evaporated under reduced pressure to give crude 7-phenylisatin 7.

Provenance & Evidence