反应详情

Preparation A3, Step 3: (1R,2S,5R)-Tert-butyl 2-((S)-2-(benzyloxycarbonylamino)-4-(methylthio)butanamido)-7-oxo-6-aza-bicyclo[3.2.1]octane-6-carboxylate (5.1 g) was dissolved in iodomethane (40 mL). The resulting solution was stirred at rt for 12 h before being concentrated in vacuo. The residue was dissolved in methylene chloride, and the resulting solution was concentrated; this was repeated to afford the salt. This material was dissolved in DMF (30 mL) and the solution was charged with Cs2CO3 (6.6 g). After 12 h, the reaction was partitioned between EtOAc and brine. The organic phase was dried (MgSO4), filtered, and concentrated. The resulting residue was purified by flash chromatography to afford (1R,2S,5R)-tert-butyl 2-((S)-3-(benzyloxycarbonylamino)-2-oxopyrrolidin-1-yl)-7-oxo-6-aza-bicyclo[3.2.1]octane-6-carboxylate (2.0 g). MS found: (M+H)+=458.6.

1. concentrationbefore being concentrated in vacuo
2. dissolutionThe residue was dissolved in methylene chloride
3. concentrationthe resulting solution was concentrated
4. customto afford the salt
5. waitAfter 12 h
6. customthe reaction was partitioned between EtOAc and brine
7. dry with materialThe organic phase was dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. customThe resulting residue was purified by flash chromatography