Triethylamine → (1S)-3-[(2S,3R)-2-(4-{[tert-butyl(dimethyl)silyl]oxy}phenyl)-1-(4-iodophenyl)-4-oxoazetidin-3-yl]-1-(4-fluorophenyl)propyl acetate

Participants

Reaction Conditions

Reaction Steps

To a solution of 0.5 g. (0.894 mmol, 1 equiv.) (3R,4S)-3-[(3S)-3-(4-fluorophenyl)-3-hydroxypropyl]-4-(4-hydroxyphenyl)-1-(4-iodophenyl)azetidin-2-one (i-6) in 5 mL anhydrous methylene chloride under inert atmosphere at 0° C. was added 0.36 mL (1.564 mmol, 1.75 equiv.) tert-butyldimethylsilyl trifluoromethanesulfonate, 0.175 mL (0.894 mmol, 1 equiv.) N-tert-butyldimethylsilylimidazole and 0.311 mL (2.234 mmol, 2.5 equivalents) triethylamine. The resulting reaction mixture was stirred at 0° C. for 15 minutes then quenched by the addition of 5 mL of sat. aq. solution of sodium carbonate. The resulting mixture was transferred to a separatory funnel, extracted with methylene chloride (3×5 mL). The combined organic extracts were dried over anhydrous Na2SO4 filtered and the solvent removed under vacuum. The residue was purified by prep. Tlc eluting with EtOAc/hexanes (2/1) to afford the title compound. m/z (ES) 696.0 (M+Na+), 614.0 (M−OAc+).

Provenance & Evidence