Hydrochloric Acid → 4-(Cyclopropanesulfonamido)-2-methylcyclopentanecarboxylic acid

Participants

Reaction Steps

To a flask containing ethyl 4-(cyclopropanesulfonamido)-2-methylcyclopentanecarboxylate (7.5 g, 27.3 mmol) was added aqueous NaOH (1N, 150 mL, 150 mmol). After stirring at ambient temperature for about 5 h, the reaction was acidified to about pH 1 with aqueous 6 N HCl and extracted with DCM (3×100 mL). The combined organic layers were washed with brine, dried over anhydrous MgSO4, filtered, and concentrated under reduced pressure to give crude 4-(cyclopropanesulfonamido)-2-methylcyclopentanecarboxylic acid containing about 5 mol % DCM (6.6 g, 97%) as a white solid: 1H NMR (DMSO-d6) δ 12.09 (s, 1H), 7.11 (d, J=8.1 Hz, 1H), 3.66-3.53 (m, 1H), 2.78-2.68 (m, 1H), 2.50 (tq, J=5.1, 7.7 Hz, 1H), 2.29-2.17 (m, 1H), 2.17-2.01 (m, 2H), 1.82 (dt, J=9.9, 12.7 Hz, 1H), 1.24 (dt, J=8.9, 12.4 Hz, 1H), 0.98-0.85 (m, 7H).

Provenance & Evidence