Procedure for the preparation of di-N-meticarbamato of 2,6-bishidroximetilpiridina. (Machine-translation by Google Translate, not legally binding)

摘要

Process for the preparation of 2,6-bis-hydroxymethylpyridine di-N-methylcarbamate, of the formula ** (see formula) ** Characterized by comprising the following steps A) reacting, in methanolic medium, pyridine-2,6-dicarboxylic acid, of formula ** (see formula) ** With an excess of ethyl bromide, with respect to the stoichiometry of the reaction, B) treat the mass resulting from stage a), devoid of the excess ethyl bromide by distillation, with sodium bromohydride, in a reduction phase, and subsequently alkalize the product, once the methanol is separated, extracting with acetone the 2,6-bis-hydroxymethylpyridine formed, C) reacting the separated 2,6-bis-hydroxymethyl-pyridine with methyl isocyanate, at temperatures not higher than 10º c, in the presence of 2 parts by weight of pyridine per 1 part of 2,6-bis-hydroxymethylpyridine, and D) raise the temperature of the reaction mass, crystallizing the product insolubilized with water. (Machine-translation by Google Translate, not legally binding)