Lithium hydroxide, monohydrate → (S)-4-methyl-2-[2-oxo-4-(5,6,7,8-tetrahydro-naphthalen-1-yloxy)-2,5-dihydro-pyrrol-1-yl]-pentanoic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of (S)-4-methyl-2-[2-oxo-4-(5,6,7,8-tetrahydro-naphthalen-1-yloxy)-2,5-dihydro-pyrrol-1-yl]-pentanoic acid methyl ester (94 mg, 0.26 mmol) in tetrahydrofuran (1.5 mL) and water (0.5 mL) was treated with lithium hydroxide monohydrate (14 mg, 0.33 mmol). The reaction was stirred at 25° C. for 3 h. At this time, the reaction was concentrated in vacuo. The residue was diluted with water (25 mL) and was extracted with diethyl ether (1×25 mL). The aqueous layer was then acidified with a 1N aqueous hydrochloric acid solution and then extracted with 10% methanol/dichloromethane (2×25 mL). The organics were then dried over magnesium sulfate, filtered, rinsed with dichloromethane and concentrated in vacuo to afford (S)-4-methyl-2-[2-oxo-4-(5,6,7,8-tetrahydro-naphthalen-1-yloxy)-2,5-dihydro-pyrrol-1-yl]-pentanoic acid (61 mg, 67%) as an orange solid: 1H NMR (300 MHz, DMSO-d6) δ ppm 0.87 (d, J=6.3 Hz, 3H), 0.93 (d, J=6.3 Hz, 3H), 1.36-1.84 (m, 7H), 2.53-2.61 (m, 2H), 2.68-2.83 (m, 2H), 4.12 (d, J=17.8 Hz, 1H), 4.24 (d, J=17.8 Hz, 1H), 4.62 (dd, J=11.2, 4.2 Hz, 1H), 4.66 (s, 1H), 6.99-7.07 (m, 2H), 7.18 (t, J=7.8 Hz, 1H), 12.84 (br. s., 1H).

Provenance & Evidence