N-bromobutanimide → (13E)-(5RS,6RS,9alpha,11alpha,15S)-5-Bromo-6,9-epoxy-11,15-bis(tetrahydropyran-2-yloxy)prost-13-enoic acid methyl ester

Participants

Reaction Steps

Under an atmosphere of nitrogen, a solution of 3.4 g of (5Z,13E)-(9α,11α,15S)-9-hydroxy-11,15-bis-(tetrahydropyran-2-yloxy)prosta-5,13-dienoic acid methyl ester in a mixture of 30 ml of methylene chloride and 6 ml of N,N-dimethylformamide was added dropwise to a suspension of 1.35 g of N-bromosuccinimide in 50 ml of methylene chloride at -20° to -10° C. and the mixture was stirred for 30 minutes at the same temperature. The reaction mixture was then poured into ice-water and extracted with diethyl ether. The extract was washed with water and an aqueous solution of sodium chloride, dried over magnesium sulphate and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using a mixture of cyclohexane and ethyl acetate (4:1) as eluent to give 3.43 g of the title compound having the following physical characteristics:

Provenance & Evidence