Trifluoroacetic acid → HCID 86754241, compound

Participants

Reaction Steps

(E)-(6R,7R)-7-tert-Butoxycarbonylamino-3-(1-isobutyl-2-oxo-pyrrolidin-3-ylidenemethyl)-8-oxo-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester (21.9 g, 35.0 mmol) was dissolved in 240 ml dichloromethane and 23 ml anisole. At 20° C. 120 ml trifluoroacetic acid were added dropwise while maintaining the temperature below 50° C. After complete addition the ice-bath was removed and the solution was stirred at ambient temperature for 2.5 hours The volatile material was then removed under reduced pressure and the remaining yellow oil was added slowly to 400 ml of diethyl ether, in which the product started to precipitate. After 1.5 hours the suspension was filtered under argon atmosphere and the remaining crystals were stirred in 150 ml of ethyl acetate for 2 hours. The suspension was filtered under argon giving the desired product as a yellow crystalline powder.

Provenance & Evidence