N-bromobutanimide → 6-bromomethyl-8-cyclopentyl-2-methylsulfanyl-8H-pyrido[2,3-d]pyrimidin-7-one

Participants

Reaction Steps

8-Cyclopentyl-6-methyl-2-methylsulfanyl-8H-pyrido[2,3-d]pyrimidin-7-one (3.5 g, 12.7 mmol) and N-bromosuccinimide (2.6 g, 14.6 mmol) in carbon tetrachloride (100 ml) were irradiated with ultraviolet light allowing the temperature to reach 45° C. over 3 hours. The mixture was filtered, washed with dilute sodium sulfite solution, then brine, and dried over anhydrous magnesium sulfate. The crude product was chromatographed on silica gel eluting with 1:1 ethyl acetate:hexane to provide 6-bromomethyl-8-cyclopentyl-2-methylsulfanyl-8H-pyrido[2,3-d]pyrimidin-7-one as a crystalline solid yielding (1.46 g, 32% yield), mp 103-105° C.

Provenance & Evidence