Trimethylsilyl triflate → HCID 86607072, compound

Participants

Reaction Steps

To 4-nitrobenzyl (4-acetyl-2-{[(allyloxy)carbonyl]amino}phenyl)acetate (10.0 g) and triethylamine (8.2 mL) in dichloromethane (100 mL) was dropped at 0° C. trifluoromethanesulfonic acid trimethylsilyl ester (11.9 g). After detecting the production of silylenol ether by TLC, (2R,3R)-3-((1R)-1-{[tert-butyl(dimethyl)silyl]oxy}ethyl)-4-oxo-2-azetidinyl acetate (6.98 g) and zinc iodide (4.65 g) were added thereto at 0° C. After stirring for 1 hour, further (2R,3R)-3-((1R)-1-{[tert-butyl(dimethyl)silyl]oxy}ethyl)-4-oxo-2-azetidinyl acetate (3.0 g) was added thereto and the mixture was stirred at room temperature for 14 hours. To the reaction mixture were added a 5% aqueous potassium hydrogensulfate solution (380 mL) and saturated brine (100 mL), and the mixture was extracted with ethyl acetate (200 mL, 2×100 mL). The organic layers were combined, dried over magnesium sulfate, filtered and the solvent was removed in vacuo. The residue was purified with column chromatography (SiO2 500 g, hexane/ethyl acetate 1:1˜1:3) to give the object compound (11.4 g, 70%) as a pale amorphous.

Provenance & Evidence