108914-10-9Relevant articles and documents
Chiral drugs related to guaifenesin: synthesis and phase properties of methocarbamol and mephenoxalone
Bredikhin, Alexander A.,Bredikhina, Zemfira A.,Zakharychev, Dmitry V.,Pashagin, Alexander V.
, p. 1239 - 1244 (2007)
The muscle relaxant methocarbamol 2 and tranquilizer mephenoxalone 3, as well as intermediate cyclic carbonate 4, have been prepared in enantiopure form by starting from enantiopure guaifenesin 1 easily available by an entrainment resolution procedure. Th
Method for preparing methocarbamol
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Paragraph 0036-0037; 0038-0039; 0040-0041; 0042-0055, (2019/07/16)
The invention discloses a method for preparing methocarbamol. The method comprises the steps that guaifenesin serves as a raw material, alkali and 4-dimethylaminopyridine serve as a catalyst, carbonicester serves as an esterification agent, and a compound shown in the formula (I) is obtained through an esterification reaction, the compound shown in the formula (I) reacts with ammonia water through an ammoniation reaction to obtain the methocarbamol shown in the formula (II), and the reaction equation of the methocarbamol is that the alkali is hydroxide or carbonate of the first main alkali metal group. Accordingly, guaifenesin serves as a raw material, the alkali and DMAP serves as the catalyst, the carbonic ester is catalyzed to be esterified and then ammonified and crystallized, and themethocarbamol is obtained. A nucleophilic reagent DMAP is used for catalysis, the carbonic ester can rapidly and highly selectively complete the reaction with hydroxide radical, and the high-yield guaifenesin ester is obtained; in addition, the dosage of the carbonic ester is small, safety and environmental protection are achieved, pollution is small, the economic benefit is high, operation is easy, and the method is suitable for industrial production.