62855-72-5

588-22-7

GENERAL PROCEDURE: To a stirred solution of 4j (2.5 g, 9.8 mmol) in methanol (30 mL) was added 3N sodium hydroxide solution (13.1 mL, 39.3 mmol). After stirring for 1 h at room temperature, the reaction mixture was diluted with water (100 mL), acidified with 3N hydrochloric acid to pH < 7, and subsequently extracted with dichloromethane (100 mL x 2). The organic layers were combined, washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to afford 3,4-dichlorophenoxyacetic acid (2.12 g, 97% yield) as a white solid. The product was characterized by 1H NMR (300 MHz, DMSO-d6): δ 7.49 (d, J=8.8 Hz, 1H), 7.21 (s, 1H), 6.92 (d, J=8.8 Hz, 1H), 4.73 (s, 2H).