Acetic acid, 2-(triphenylphosphoranylidene)-, ethyl ester → Benzhydryl (E)-(2S,3S,5R)-3-(2-ethoxycarbonyl-vinyl)-3-methyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

500 mg (1.30 mmol) of benzhydryl (2S,3R,5R)-3-formyl-3-methyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate were dissolved in 20 ml of THF under argon and treated with 500 mg (1.40 mmol) of ethoxycarbonylmethylene-triphenylphosphorane. The yellow solution was stirred at 50° C. for 75 minutes and subsequently concentrated. The residue remaining behind was chromatographed over silica gel (0.040-0.063 mm particle size) with ethyl acetate:hexane (9:16) as the eluent.

Provenance & Evidence