6836-22-2

6836-21-1

6836-22-2

Step 3 Synthesis of (7-methoxy-1-naphthyl)acetic acid: To a solution of methanol (12 mL) containing ethyl 7-methoxy-1-naphthylacetate (2.38 g, 9.8 mmol), sodium hydroxide (0.62 g, 15.6 mmol) and water (6 mL) were added. The reaction mixture was heated at 40°C for about 2 hours with continuous stirring. Upon completion of the reaction, the mixture was concentrated under reduced pressure and the residue was diluted with 50 mL of water and extracted with ether (4 x 25 mL). The aqueous phase was acidified with concentrated hydrochloric acid to pH=2. After conventional extraction and post-treatment, the title compound 7-methoxy-1-naphthaleneacetic acid was obtained as an off-white solid (1.9 g, 90% yield). The product was confirmed by 1H NMR (300 MHz, CD3OD): δ 3.9 (s, 3H), 4.03 (s, 2H), 7.15 (dd, J = 9.0, 2.4 Hz, 1H), 7.27-7.41 (m, 4H), 7.76 (m, 2H); LC-MS showed the molecular ion peak as 215 (M + H)+.