Acetic Acid → allyl (5R,6S)-3-(1-allyloxycarbonylpyrrolidin-3-yl)-6-[(1R)-1-hydroxyethyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate

Participants

Reaction Steps

To a solution of allyl (5R,6S)-3-(1-allyloxycarbonylpyrrolidin-3-yl)-6-[(1R)-1-t-butyldimethylsilyoxyethyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (2.9 g) in tetrahydrofuran (30 ml) were added acetic acid (3.3 ml) and a 1M solution of tetrabutylammonium fluoride in tetrahydrofuran (28.7 ml) at 0° C. under nitrogen. After standing at ambient temperature for 7 hours and additionally at 5° C. for 14 hours, the reaction mixture was taken up into a mixture of ethyl acetate and water. After adjusting pH to around 7 with an aqueous sodium hydrogen carbonate, the organic layer was separated, washed in turn with water and brine, and dried over magnesium sulfate. Removal of the solvent gave a residue, which was chromatographed on silica gel eluting with a mixture of n-hexane and ethyl acetate (1:2, V/V) to give allyl (5R,6S)-3-(1-allyloxycarbonylpyrrolidin-3-yl)-6-[(1R)-1-hydroxyethyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (0.94 g).

Provenance & Evidence