Monobromination of 2-aminopyrazine was achieved by modification of the method reported by Sato. 3-Bromo-2-aminopyrazine reacted with various alkyl, allyl and arylstananes to form 3-substituted 2-aminopyrazines in moderate to good yields.

3,5-Dibromo-2-aminopyrazine prepared by Sato's method gave 3-aryl or 3,5-diaryl derivatives depending on the amount of arylstananes. The higher reactivity of the 3 position might be explained by the chelation effect of an amino group at 2 position.