Study On The Synthesis Of 2-mercapto-4-methyl Pyrimidine Hydrochloride

2-mercapto-4-methyl pyrimidine hydrochloride is an important intermediate in sulfanilamide medicine, it can be widely used in chemical industry and pharmacy. The author made an deeper investigation into its synthesis.This paper describes the synthesis process: the condensation reaction are taken place by dropping the mixture of acetone and methyl formate into methanol solution of sodium methoxide to form sodium formyl acetone, then the additive reaction are carried out between sodium formyl acetone and methanol to form 4,4-dimethoxy-2-butanone in the presence of sulfuric acid, finally in the methanol solution of hydrochloride acid, 4,4-dimethoxy-2-butanone and thiourea cyclize to form the final product. During the experiments, we study all the influent factors to each reaction. The main influent factors to the condensation reaction are raw material molar ratio, reaction temperature and reaction time, oxygen and water. It can be acquired satisfying result when the reaction is taken place under suitable condition and completely cut off oxygen and moisture. The main influent factors to the additive reaction are acid, reaction temperature, oxygen and water. Using suitable process and optimizing the reaction condition, the total yield of these two steps is 62.8%. There are also some factors like raw material molar ratio, reaction temperature and time, water content influent the cyclization reaction. The cyclization reaction yield is 95.1% under suitable conditions. The whole process yield is 60%.This study provides an important technical foundation to the industrialization of the 2-mercapto-4-methyl pyrimidine hydrochloride.