Dimethylformamide → methyl 3-(3-bromo-2-oxopyrazin-1(2H)-yl)-4-chlorobenzoate

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Reaction Conditions

Reaction Steps

A suspension of methyl 4-chloro-3-(2,3-dioxo-3,4-dihydropyrazin-1(2H)-yl)benzoate (Example 330d, 8 g) in DCM (80 mL) was treated with N,N-dimethylformamide (0.220 mL) and oxalyl bromide (2.94 mL) dropwise over 5 min at room temperature under nitrogen. The resulting mixture was stirred at 20° C. for 16 h. The reaction mixture turned black and was evaporated to afford crude product. Purification (SiO2 chromatography eluting with 30% diethyl ether in dichloromethane) gave the subtitle compound (6.33 g).

Provenance & Evidence