(2S)-2-amino-3,3-dimethyl-1-morpholin-4-ylbutan-1-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of (S)-2-(benzyloxycarbonylamino)-3,3-dimethylbutanoic acid (2.0 g, 7.54 mmol) in DMF (10 mL) were added morpholine (1.31 g, 15.1 mmol) and DIEA (3.95 mL, 22.62 mmol). TBTU (3.63 g, 11.31 mmol) was added in three portions 15 minutes apart. The reaction stirred at room temperature for 2 hours. DMF was removed under vacuum and the residue was partitioned between ethyl acetate and saturated sodium bicarbonate. The organic layer was separated, dried over sodium sulfate, filtered and concentrated under reduced pressure. The resulting crude material (2.11 g, 7.54 mmol) was combined with palladium on carbon, 10% dry basis, (0.29 g, 2.69 mmol) in MeOH (15 mL) and placed on a Parr Shaker under H2 atmosphere, 20 psi, for 3 hours. The reaction was filtered through a celite plug and concentrated under reduced pressure to provide 1.46 g (7.31 mmol) of intermediate 77D. LCMS (+ESI) m/z 201.1 [M+H]+. DMF was removed under vacuum the residue was partitioned between ethyl acetate and saturated sodium bicarbonate The organic layer was separated dried over sodium sulfate filtered concentrated under reduced pressure dry basis, (0.29 g, 2.69 mmol) in MeOH (15 mL) 20 psi, for 3 hours The reaction was filtered through a celite plug concentrated under reduced pressure