Bromine → HCID 57779807, compound

Participants

Reaction Conditions

Reaction Steps

At −78° C., a solution of 202 mg (0.75 mmol) of 4-[[(6-chloropyridin-3-yl)methyl](2-hydroxyethyl)-amino]furan-2(5H)-one (II-1) in 7 ml of tetrahydrofuran, also cooled to −78° C., is added to a mixture of 0.6 ml (1.50 mmol) of a 2.5M solution of n-butyllithium in hexane and 3 ml of tetrahydrofuran. After 20 minutes of stirring at −78° C., 39 μl (0.75 mmol) of bromine are added a little at a time, and stirring at −78° C. is continued for a further 30 min. After addition of saturated aqueous ammonium chloride solution, the mixture is warmed to room temperature and extracted with ethyl acetate. The combined organic phase is dried over magnesium sulphate and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel (silica gel 60, Merck, particle size: 0.04 to 0.063 mm) using the mobile phase mixture dichloromethane:methanol (95:5) gives 67 mg (32% of theory) of 1-[(6-chloropyridin-3-yl)methyl]-2,3-dihydro-1H-furo[2,3-b][1,4]oxazin-6(4aH)-one.

Provenance & Evidence