Lithium Hydroxide → 4-(2-Carboxy-4-fluoro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

4-(4-Fluoro-2-methoxycarbonyl-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (5.5 g, 16.2 mmol) is dissolved in THF (40 mL) and 1 M aqueous LiOH (33 mL) is added at room temperature. The solution is warmed to 50° C. for 3 h. THF is removed under reduced pressure and the aqueous part is washed with 50% EtOAc in hexane. The aqueous part is acidified with 1 M aqueous HCl followed by extraction with EtOAc (3×50 mL). Combined organic layer is dried over anhydrous MgSO4 and concentrated under reduced pressure to afford 4-(2-carboxy-4-fluoro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester as a solid (4.9 g, 98%).

Provenance & Evidence