Propargyl bromide → (3S)-3-ethoxycarbonyl-4-(2-propynyl)morpholine

Reaction equation

Cl.[CH2:2]([O:4][C:5]([C@@H:7]1[CH2:12][O:11][CH2:10][CH2:9][NH:8]1)=[O:6])[CH3:3].[CH2:13](Br)[C:14]#[CH:15].C(=O)([O-])[O-].[K+].[K+]>CN(C)C=O>[CH2:2]([O:4][C:5]([C@@H:7]1[CH2:12][O:11][CH2:10][CH2:9][N:8]1[CH2:15][C:14]#[CH:13])=[O:6])[CH3:3]

Participants

Procedure

A mixture of (3S)-3-ethoxycarbonylmorpholine hydrochloride (0.3 g), propargyl bromide (0.34 ml) and potassium carbonate (0.91 g) in N,N-dimethylformamide (10 ml) was stirred at room temperature for 1 hour and then the solvent was removed under reduced pressure. Ethyl acetate and sodium hydrogen carbonate solution were added to the residue and the organic layer was separated, dried over magnesium sulfate, and evaporated in vacuo. The residue was purified by column chromatography on silica gel with a mixture of ethyl acetate and n-hexane (3:7) as an eluent to give (3S)-3-ethoxycarbonyl-4-(2-propynyl)morpholine (0.22 g) as an oil.