p-Toluenesulfonic acid → 5-Methoxy-1H-indene

Participants

Reaction Conditions

Reaction Steps

Step AA (2): To a solution of crude methyl 6-methoxy-2,3-dihydro-1H-inden-1-ol from Step AA (1) (24.3 g) in benzene (100 mL) was added pTSA (250 mg), and the resulting solution was heated at 90° C. for 3 h with a Dean-Stark trap to remove water. Saturated sodium bicarbonate was added, the aqueous layer was extracted with EtOAc (×3), and the combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered, and evaporated. The crude product was distilled under vacuum to provide 5-methoxy-1H-indene as a colorless liquid (10 g). 1H NMR (400 MHz, CDCl3): 7.33 (1H, d), 6.96 (1H, d), 6.81 (1H, m), 6.75 (1H, m), 6.56 (1H, m), 3.82 (3H, s), 3.33 (2H, m).

Provenance & Evidence