[C:1]([CH2:3][C:4]([CH3:9])(O)[CH2:5][C:6]#[N:7])#[N:2].[BrH:10]>C(O)(=O)C>[NH2:2][C:1]1[N:7]=[C:6]([Br:10])[CH:5]=[C:4]([CH3:9])[CH:3]=156.4 g of 1,3-dicyano-2-methyl-2-hydroxypropane was added carefully to a 33% solution of hydrogen bromide in glacial acetic acid at ice-bath temperature. The reaction mixture was then stirred for 3 days at ambient temperature. The solvent was removed in vacuo and the residual oil was brought to pH 12 with a 10 molar aqueous solution of sodium hydroxide. This alkaline solution was extracted three times each with 100 ml ethyl acetate. The combined organic layers were dried with magnesium sulphate and the solvent removed in vacuo. 56 g (66%) of 6-amino-2-bromo-4-methylpyridine was obtained as a colourless solid of melting point 99° C.
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