Sodium Iodide → HCID 86752082, compound

Participants

Reaction Steps

To a solution of 4-nitrobenzyl 2-[(3S ,4R)-3-[(1R)-1(tert-butyldimethylsilyloxy)-ethyl]-4-[(4Z)-methoxy-2-oxobut-3-en-1-yl]-2-azetidinon-1-yl]-2-hydroxyacetate (8.49 g, 15.8 mmol) in THF (300 ml) at -20° C. was added successively 2,6-lutidine (5.5 ml, 47.5 mmol) and thionylchloride (1.7 ml, 24 mmol). The cooling bath was removed and the reaction mixture stirred at ambient temperature for 30 minutes. The mixture was filtered, the solvent evaporated, the residue redissolved in toluene, the solution again filtered and evaporated. The residue was taken up in THF (300 ml) and triphenylphosphine (8.3 g, 32 mmol), 2,6-lutidine (3.7 ml, 32 mmol) and sodium iodide (0.5 g, 32 mmol) were added successively. The reaction mixture was stirred at ambient temperature for 1 hour, filtered and evaporated. The residue was purified by flash chromatography on silica using dichloromethane/ethyl acetate (8:2) as eluant to afford the title compound 4-nitrobenzyl 2-[(3S,4R)-3[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(4Z)-methoxy-2-oxobut-3-en-1-yl]-2-azetidinon-1-yl]-2-(triphenylphosphoranylidene)acetate (7.5 g, 58% ).

Provenance & Evidence