Sodium Chloride → 2-(1-((Tert-butoxy)carbonyl)piperidin-4-yl)-1,3-thiazole-4-carboxylic acid

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Reaction Steps

To a solution of 1,1-dimethylethyl 4-[4-(ethoxycarbonyl)-2-thiazolyl]-1-piperidinecarboxylate (i.e. the product of Example 1, Step A) (3.4 g, 10 mmol) in 20 mL of methanol and 20 mL of tetrahydrofuran was added 1 N aqueous NaOH solution (15 mL), and the resulting mixture was stirred at ambient temperature for 1.5 h. The reaction mixture was concentrated under reduced pressure, diluted with water and acidified with excess 20% aqueous citric acid solution to give a gummy precipitate. Ethyl acetate (30 mL) was added to dissolve the precipitate, the aqueous layer was saturated with NaCl, and the reaction mixture was extracted with ethyl acetate. The extract was dried over MgSO4 and concentrated under reduced pressure to give 3.09 g of the title compound as a tan solid.

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