Bromine → 6-Benzyl-5,6,7,8-tetrahydro-1,6-naphthyridin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

Bromine (750 μl, 14.6 mmol) in glacial acetic acid (5 ml) was added dropwise over 5 minutes to (6-benzyl-3,4,5,6,7,8-hexahydro-1H-[1,6]naphthyridin-2-one (3.37 g, 13.9 mmol) (reference WO9830560) dissolved in glacial acetic acid (50 ml) at 100° C. The mixture was heated at 100° C. for 2.5 hours and then was cooled to room temperature. The solvent was evaporated under reduced pressure and the residue was basified with 10% sodium carbonate solution (50 ml). The aqueous mixture was extracted with chloroform (4×50 ml) and the combined organic solutions were dried over sodium sulphate and evaporated under reduced pressure. The residue was purified by chromatography on silica gel using methanol in dichloromethane (gradient from 0:100 to 3:97) to give the title compound as yellow crystals (1.5 g).

Provenance & Evidence