Method for preparing 3-amino-2-chloro-4-alkylpyridine or-4-arylpyridine

A process for preparing 3-amino-2-chloro-4-alkyl-pyridine, wherein the alkyl moiety is of 1 to 3 carbons, which process comprises:

• (a) reacting 3-amino-4-alkyl-pyridine, wherein the alkyl moiety is of 1 to 3 carbons, with HCl/H.sub.2 O.sub.2 in aqueous solution;
• (b) adjusting the pH of the reaction medium to between -1 and +1 by the addition of a base, and extracting the by-products into a halohydrocarbon solvent;
• and,
• (c) adjusting the pH of the aqueous phase to between 3.5 and 5 by the addition of a base, and isolating the 3-amino-2-chloro-4-alkyl-pyridine so produced by extraction into a halohydrocarbon solvent, followed by evaporation of the solvent;
• or,
• in the case of derivatives which are not readily soluble, adjusting the pH of the aqueous phase to between 7 and 14, and directly precipitating the product.

A process for preparing 3-amino-2-chloro-4-methyl-pyridine, which process comprises:

• (a) reacting 3-amino-4-methyl-pyridine with HCl/H.sub.2 O.sub.2 in aqueous solution;
• (b) adjusting the pH of the reaction medium to between -1 and +1 by the addition of a base, and extracting the 2,6-dichloro-3-amino-4-methylpyridine into methylene chloride;
• and,
• (c) adjusting the pH of the aqueous phase to between 3.5 and 5 by the addition of a base, and isolating the 3-amino-2-chloro-4-methyl-pyridine so produced by extraction into methylene chloride, followed by evaporation of the methylene chloride.