Amino to Bromo Substituents

Ellingson and Henry (798) first showed that 2-amino-3-methoxycarbonylpyrazine 

Preparations of halogenopyrazines utilizing primary syntheses from a-(p-toluenesulfonyloxyimino)malononitrile have been discussed in Section II.7. a-Aminophenylacetonitrile with chloral (or bromal) were claimed to give 2,3-dichloro(or dibromo)-5-phenylpyrazine (830, 893), but this has now been shown to be in error (829). 

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