Acetic acid, 2-(triphenylphosphoranylidene)-, methyl ester → HCID 86586485, compound

Participants

Reaction Conditions

Reaction Steps

A solution containing 16.3 g of (4RS)-4-allyl-1-benzyloxycarbonylpiperidin-3-one in 200 cm3 of toluene was stirred under reflux with methyl (triphenylphosphoranylidene)acetate, under an inert atmosphere, for 16 hours. After cooling to about 20° C., the reaction mixture was concentrated under reduced pressure (5 kPa) at a temperature in the region of 40° C., the residue obtained, solubilized in 50 cm3 of dichloromethane in the hot state, was purified by chromatography, under a nitrogen pressure of 50 kPa, on a column of silica gel (particle size 20-45 μ; diameter 10 cm; height 45 cm), eluting with a cyclohexane-ethyl acetate (80/20 by volume) mixture. 250-cm3 fractions were collected. Fractions 13 to 15 were combined and then concentrated as above. 5.8 g of methyl (4RS)-4-allyl-1-benzyloxycarbonylpiperidin-3-ylidenacetate (Z isomer) were obtained in the form of a colorless oil.

Provenance & Evidence