Ethyl Acetate → HCID 15086182, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-nitrobenzyl (4R)-2-diazo-4-[(2R,3S)-3-{(1R)-1-hydroxyethyl}-4-oxoazetidin-2-yl]-3-oxopentanoate (0.28 g) in 1.2-dichloroethane (15 ml) was added rhodium (II) acetate (2 mg) under reflux. The mixture was reluxed for 30 minutes under nitrogen atmosphere and concentrated under reduced pressure to give a syrup. The syrup was dissolved in acetonitrile (15 ml) and N,N-diisopropyl-N-ethylamine (0.37 ml). Diphenyl chlorophosphate (0.16 ml) was added thereto at -10--5° C. in a nitrogen stream, followed by stirring at -10--5° C. for 30 minutes. To the solution were added a solution of (2S,4S)-2-(imidazol-1-yl)methyl-4-mercapto-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (0.26 g) in acetonitrile (2 ml) at -30--25° C. and the mixture was stirred at 0-10° C. for 2 hours. The mixture was poured into ethyl acetate (75 ml), washed with water (50 ml ×2), dried over magnesium sulfate and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on sili.COPYRGT.a gel (20 g) and eluted with a mixture of acetone and dichloromethane (50:50, V/V) to give 4-nitrobenzyl (4R,5S,6S)-6-[(lR)-1-hydroxyethyl]-3-[(2S,4S)-2-(imidazol-1-yl)methyl-1-(4-nitrobenzyloxycarbonyl)pyrrolidin-4-yl]thio-4-methyl -7-oxo-1-azabicyclo[3.2.0]-hept-2-ene-2-carboxylate (0.19 g).

Provenance & Evidence