Sodium Hydroxide → 5-[1-(tert-Butoxycarbonyl)piperidin-4-yl]-1,3-oxazole-4-carboxylic acid

Participants

Reaction Steps

To a stirred solution of tert-butyl 4-[4-(methoxycarbonyl)-1,3-oxazol-5-yl]piperidine-1-carboxylate (8.90 g, 28.7 mmol) in methanol (340 mL) was added 1 M NaOH solution (86 mL). After being stirred at room temperature for 2 h, the reaction mixture was concentrated to about one quarter. To this mixture was added ethyl acetate (80 mL) and the mixture was acidified with 10% KHSO4 solution under ice-cooling. The organic layer was separated, washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The resulting light yellow solid was triturated with diisopropyl ether to give the title compound (7.32 g, 86%) as a light yellow solid.

Provenance & Evidence