Research On Synthesis Process Of Fexofenadine

Allergic disease is common of a kind of disease and its incidence continuously. Theantihistamine can effective treatment for the allergic disease,alleviate the suffering ofpatients.The fexofenadine appears to be quite a promising one among the newantihistamines since it fulfills almost all the criteria for an ideal H1antagonist.Afterlong-term clinical validation, fexofenadine has obvious curative effect. It has little sideeffect and no sedative function,and very good market prospects.This topic in the domestic and foreign research report based on the author putsforward two innovation.First, we should take cyclization reaction before oxidation withthe potassium to protect the side chain on benzene ring and prevent the generation of otherproducts.Then we open the ring after oxidation,improving the purity and yield of product.Second,we shouid take reduction reaction before N-alkylation reaction to reduce theconsumption of α,α-two phenly-4-piperidine methanol and the cost of reaction.We use benzene and methallyl allyl alcohol ester as starting reactant,via the steps ofFriedel-Crafts alkylation reaction,hydrolysis,oxidation,esterification reaction,reductionreaction get middle product.The followed reaction was N-alkylation reaction and4-{1-hydroxy-4-[4-(hydroxydi-phenyl)-piperidine]butyl}-α,α-dimethylbenaen acetate wasobtained.Then we can get the final product fexofenadine after hydrolysis.In the synthesisprocess of the reaction time,reaction temperature,solvent selection and other factors wereconsidered,constantly optimize the reaction conditions,improve the target productfexofenadine set the final production rate.