N-bromosuccinimide (0.55 g, 3.1 mmol) was added to 1,4-dioxane/water (3:1) (20 mL). 2-(1-Ethoxyvinyl)-5-phenyl-N-(pyridin-2-ylmethyl)quinazolin-4-amine (0.59 g, 1.5 mmol) was then added in small portions at 0° C. Upon completion of addition, the reaction mixture was stirred at room temperature for 20 min. After this time, water was added and the aqueous portion was extracted twice with DCM. The combined organic layers were dried, filtered and evaporated under reduced pressure to yield 2-bromo-1-(5-phenyl-4-(pyridin-2-ylmethylamino)quinazolin-2-yl)ethanone (600 mg, 69% purity by LCMS), which was used without further purification. LCMS Method Y: retention time 1.996 min, [M+1]=433.
