Triethylamine → 1-(1(S)-t-butoxycarbonylethyl)-3(R)-azido-4(S)-phenylazetidin-2-one

Participants

Reaction Steps

To 75 ml. of a solution of N-benzylidene-1(S)-t-butoxycarbonylethylamine (5.07 g., 21.7 mmol) and triethylamine (4.84 g., 47.8 mmol) in methylene chloride, there was gradually added dropwise 75 ml. of a solution of azidoacetyl chloride (5.19 g., 43.5 mmol) in methylene chloride at -78° C. After stirring at -78° C. to room temperature for 14 hours, the reaction mixture was washed with water and then with a saturated saline solution, followed by drying over anhydrous magnesium sulfate. After removal of the solvent by distillation, the residue was subjected to silica gel column chromatography, using hexane-ethyl acetate (3:1) as an eluent, to give 1-(1(S)-t-butoxycarbonylethyl)-3(S)-azido-4(R)-azetidin-2-one (2.68 g., yield: 39%) and 1-(1(S)-t-butoxycarbonylethyl)-3(R)-azido-4(S)-phenylazetidin-2-one (2.82 g., yield: 41%).

Provenance & Evidence