Benzyl 2-(triphenyl-lambda5-phosphanylidene)acetate → Benzhydryl (E)-(2S,3S,5R)-3-(2-benzyloxycarbonyl-vinyl)-3-methyl-7-oxo-4-thia-1-aza-bicyclo[3.2.0]heptane-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

763 mg (2.0 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 15 ml of THF under argon, treated with 821 mg (2.0 mmol) of benzyloxycarbonylmethylene-triphenylphosphorane and the orange solution was stirred at 50° C. for 2 hours. It was left to cool to room temperature, the solvent was removed on a rotary evaporator and the red-brown oil was chromatographed over silica gel (particle size 0.040-0.063 mm) with ethyl acetate:hexane (9:16) as the eluent.

Provenance & Evidence