Reaction Steps
A solution of 10.0 g of 3-oxo-indan-1-carboxylic acid (56.8 mmol, 1.0 equivalent) and 0.25 mL of concentrated sulfuric acid in 20 mL of methanol was heated to a reflux for 4 hours. The reaction mixture was then cooled to room temperature and diluted with 100 mL of methyl-tert-butyl alcohol. The organic solution was washed twice with 60 mL of a saturated aqueous sodium bicarbonate solution, and once with 50 mL of a saturated aqueous sodium chloride solution. The organic layer was dried over anhydrous sodium sulfate and concentrated. The title compound crystallized as a white solid upon concentration, (10.4 g, 96%); mp: 46-47° C.; 1H NMR (400 MHz, CDCl3): δ 7.74 (d, J=7.6 Hz, 1H), 7.68 (d, J=7.6 Hz, 1H), 7.62 (t, J=7.6 Hz, 1H), 7.44 (t, J=7.6 Hz, 1H), 4.29 (dd, J=8.0, 3.4 Hz, 1H), 3.76 (s, 3H), 3.13 (dd, J=19.1, 3.4 Hz, 1H), 2.86 (dd, J=19.1, 8.0 Hz, 1H); 13C NMR (100 MHz, CD3OD): δ 204.4, 172.5, 151.3, 136.5, 135.2, 129.1, 126.7, 124.1, 52.9, 43.8, 39.7; IR (neat, cm−1): 2954, 1710, 1602, 1462, 1435, 1403, 1319, 1241, 1206, 1168, 1092, 1044, 1014, 986, 881, 837, 760, 686, 580, 538.
