Lithium Hydroxide → 1-((Tert-butoxy)carbonyl)-4,4-difluoropiperidine-2-carboxylic acid

Participants

Reaction Steps

To a solution of 1-tert-butyl 2-methyl 4,4-difluoropiperidine-1,2-dicarboxylate, 13e, (4.6 g, 16.5 mmol) in THF (18 mL), methanol (18 mL) and H2O (9 mL) was added lithium hydroxide (3.45 g, 82.22 mmol). The reaction mixture was stirred at room temperature for 1 hour. All volatiles were removed under reduced pressure. The residue was diluted with a slight amount of water and ether. The layers were separated and the organic phase was discarded. The aqueous phase was acidified to pH 3 with the addition of aqueous saturated KHSO4 solution. The product was extracted with EtOAc. The organic phase was washed with water, dried over MgSO4, filtered and evaporated to dryness. The resulting product was used without further purification.

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