Hydrochloric Acid → 2-(7-(3-Cyano-4-isopropoxybenzyloxy)-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl)acetic Acid

Participants

Reaction Steps

Ethyl 2-(7-(3-cyano-4-isopropoxybenzyloxy)-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl)acetate (1.32 g, 3.05 mmol) was dissolved in dioxane (34 mL) and 1.0 M aqueous LiOH (9.16 mL, 9.16 mmol) was added. The reaction was stirred at room temperature for 6 h and then warmed to 35° C. and stirred for one additional hour. After cooling to room temperature, the reaction was acidified to pH 3 with 1.0 M HCl and partitioned between water and ethyl acetate. The organics were removed and the aqueous layer was extracted twice with ethyl acetate. The combined extracts were dried over sodium sulfate, filtered and concentrated to give the title compound (1.23 g). LCMS m/z=405.6 [M+H]+; 1H NMR (400 MHz, DMSO-d6) δ ppm 1.32 (d, J=5.9 Hz, 6H), 2.03-2.13 (m, 1H), 2.35 (dd, J=15.9, 9.0 Hz, 1H), 2.58-2.77 (m, 4H), 3.41-3.51 (m, 1H), 4.79 (septet, J=5.9 Hz, 1H), 5.01 (s, 2H), 6.69 (dd, J=8.8, 2.4 Hz, 1H), 6.91 (d, J=2.4 Hz, 1H), 7.19 (d, J=8.6 Hz, 1H), 7.28 (d, J=8.8 Hz, 1H), 7.70 (dd, J=8.8, 2.3 Hz, 1H), 7.76 (d, J=2.1 Hz, 1H), 10.45 (s, 1H), 12.1 (bs, 1H).

Provenance & Evidence