The invention discloses 3,5-diaminopyridine and a preparation method of 3,5-dimethoxycarboxylaminopyridine. The preparation method comprises the following steps: using 3,5-dimethylpyridine to perform oxidation reaction so as to obtain 3,5-pyridinedicarboxylic acid; using 3,5-pyridinedicarboxylic acid to perform acyl chlorination and obtain 3,5-pyridinedicarbonyl
chloride; using 3,5-pyridinedicarbonyl
chloride to perform ammoniation reaction to obtain 3,5-pyridinedimethylformamide; and performing Hofmann degradation on the 3,5-pyridinedimethylformamide to prepare 3,5-diaminopyridine or 3,5-dimethoxycarboxylaminopyridine. In the invention, 3,5-dimethylpyridine is used as
raw material to design the synthetic
route of the target compound, the
reaction conditions of each step are mild, the product purity and yield are obviously increased, the yield is more than 70%; and the aftertreatment of each step of the provided synthetic
route is simple, the method is green and
environmentally friendly, the oxidation product is
solid manganese dioxide, the oxidation product can be recycled through filtering, and the compound 2 can be used to perform the next step without being separated.