Ethyl Acetate → (E)-(R)-2-((S)-1-Hydroxy-2-morpholin-4-yl-2-oxo-ethyl)-5-phenyl-pent-4-enoic acid methyl ester

Participants

Reaction Steps

Lithium hexamethyldisilazide (1M in THF, 14.5 ml, 14.5 mmol) was added to a solution of (S)-3-Hydroxy-4-morpholin-4-yl-4-oxo-butyric acid methyl ester (1.5 g, 6.9 mmol) in dry THF (15 ml) at −78° C. under N2 and stirred for 30 min. Cinnamyl bromide (1.6 g, 7.32 mmol) was then added, the reaction mixture stirred at −78° C. for 2 hrs, warmed up to room temperature and stirred overnight at room temperature. The reaction was quenched with saturated ammonium chloride solution, adjusted the pH to 6 with 1N HCl and extracted with ethyl acetate. Combined ethyl acetate extracts were dried over MgSO4 and concentrated under reduced pressure to give pale brown solid. Column chromatography on silica eluting with a mixture of ethyl acetate and methylene chloride gave the title compound as pale, yellow solid (1.15 g).

Provenance & Evidence