Sulfuric Acid → HCID 89618025, compound

Participants

Reaction Steps

2-Ethoxycarbonylmethyl-3-oxo-indan-2,5-dicarboxylic acid-2-ethyl ester-5-methyl ester (Step 2, 530 mg, 1.5 mmol) in 1.3 ml mixture of 6 N HCl: acetic acid (1:1) was heated to reflux for 3 h. The reaction mixture was evaporated to dryness, 10 ml water was added and extracted with ethyl acetate. Organic layer was washed with brine, dried over sodium sulphate and then concentrated. The crude product was washed with hexane and precede next step without further purification (530 mg). To a stirred solution of 2-carboxymethyl-3-oxo-indan-5-carboxylic acid (3.5 g, 14.9 mmol) in methanol (53 ml) was added concentrated sulphuric acid (5.6 ml) at 0° C. After addition temperature of the reaction mixture was slowly raised to room temperature and then heated to reflux for 5 h. The reaction mixture was evaporated. Water was added and extracted with ethyl acetate. Ethyl acetate layer was washed with saturated aqueous sodium bicarbonate, brine, dried and concentrated under reduced pressure. Crude was purified by column chromatography using acetone/hexane (25%) to yield a desired product (2.7 g). 1H NMR (400 MHz, CDCl3) d 8.44 (1H, s), 8.30 (1H, d), 7.57 (1H, d), 3.95 (3H, s), 3.78 (3H, s), 3.53 (1H, dd), 3.09-2.93 (3H, m), 2.71 (1H, dd) ppm.

Provenance & Evidence