Methyl 4-bromo-2-(bromomethyl)benzoate → (R)-methyl 4-bromo-2-((2-chloro-6a,7,9,10-tetrahydro-[1,4]oxazino[3,4-h]pteridin-5(6H)-yl)methyl)benzoate

Participants

Reaction Steps

(R)-2-chloro-5,6,6a,7,9,10-hexahydro-[1,4]oxazino[3,4-h]pteridine (200 mg, 0.882 mmol) (PREPARATION x2, 200 mg, 0.882 mmol) was dissolved in DMSO (5 mL). Sodium tert-butoxide (102 mg, 1.059 mmol) was then added to give a brown solution. After 5 minutes, methyl 4-bromo-2-(bromomethyl)benzoate (299 mg, 0.971 mmol) was added dropwise. The reaction was stirred overnight at room temperature, then quenched with aqueous saturated NH4Cl. The reaction mixture was diluted with ethyl acetate and washed with aqueous saturated NH4Cl (3×25 mL). The combined organic layers were dried over MgSO4, filtered, and concentrated in vacuo. The crude product was loaded onto an ISCO® silica gel cartridge (12 g) and eluted using an ethyl acetatehexane gradient. The product was collected and concentrated in vacuo to afford the title compound as a white foam (164 mg, 41%). ESI-MS m/z [M+H]+ calc'd for C18H18BrClN4O3, 453.04; found 453.2.

Provenance & Evidence