478837-18-2

The general procedure for the synthesis of tert-butyl 3-hydroxy-8-azabicyclo[3.2.1]octane-8-carboxylate using 3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylic acid as a starting material was as follows: sodium borohydride (178 mg, 4.7 mmol) was slowly added to a solution of tert-butyl 3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylate (0.50 g, 2.2 mmol) at room temperature. butyl ester (0.50 g, 2.2 mmol) in a solution of ethanol (10 mL). The reaction mixture was stirred continuously for 1 hour at room temperature. Upon completion of the reaction, the reaction was quenched with saturated ammonium chloride solution (30 mL) followed by extraction with ethyl acetate (3 x 20 mL). The organic phases were combined, washed sequentially with water and brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford the title compound tert-butyl 3-hydroxy-8-azabicyclo[3.2.1]octane-8-carboxylate (463 mg, 92% yield) as a mixture of endo and exo stereoisomers. The product was analyzed by GC-MS (EI) and the molecular ion peak (M+) of molecular formula C12H21NO3 was 227.

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