Methanol → 4-{(S)-1-[(S)-6-(2-Hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazinan-3-yl]-ethyl}-benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

NEt3 (0.47 mL) and [1,1′-bis(diphenylphosphino)ferrocene]-dichloropalladium(II)dichloromethane complex (0.15 g) were added to a solution of 3-[(S)-1-(4-bromo-phenyl)-ethyl]-(S)-6-(2-hydroxy-2-methyl-propyl)-6-phenyl-[1,3]oxazinan-2-one (1.04 g) in MeCN (2.5 mL), methanol (20 mL), and N,N-dimethylformamide (5 mL). The resulting mixture was sparged with argon for 5 min and then transferred to a pressure-resistant vessel that was filled with CO (5.5. bar). The mixture was heated to 70° C. and stirred at this temperature for 18 h before another portion of [1,1′-bis(diphenylphosphino)ferrocene]-dichloropalladium(II)dichloromethane complex (0.15 g) was added. After stirring at 70° C. for another 4 h, the mixture was cooled to ambient temperature, filtered, and concentrated under reduced pressure. The residue was taken up in ethyl acetate and the resulting mixture was washed with water and brine and dried (MgSO4). The solvent was removed and the residue was purified by chromatography on silica gel (cyclohexane/ethyl acetate 40:60→0:100) to afford the title compound as an oil.

Provenance & Evidence