Synthesis of 2‐amino‐5‐ethoxypyridine

Abstract

Abstract 2‐Amino‐5‐ethoxypyridine has been synthesised starting from 2‐amino‐pyridine and 3‐ethoxypyridine. The synthesis from 2‐aminopyridine via 2‐amino‐5‐bromopyridine is not a feasible method of preparation because of the occurrence of various side‐reactions in the action of sodium ethylate on the latter substance in the presence of copper powder as a catalyst. The bromine atom is then replaced mainly by hydrogen instead of by ethoxyl, while simultaneously, one of the hydrogen atoms in the amino group is replaced by an ethyl group. An alternative route via 5‐bromo‐2‐nitro‐pyridine leads to no better result, since in this compound sodium ethylate replaces not the bromine atom but the nitro group by ethoxyl. 2‐Amino‐5‐ethoxypyridine can be prepared in a satisfactory manner, however, from 3‐ethoxypyridine via 2‐bromo‐3‐ethoxy‐6‐nitropyridine.