Research on Esterification in Fluorous Biphase System

It was studied that esterification of equal-molecular carboxylic acid and alcohol catalysed by conc.sulfuric acid was conducted in perfluorous solvent without removing any product in the process of reaction.Compared with the reaction without perfluorous solvent,perfluorous nonene reduces the temperature of esterifications by 10~37 ℃,and raises the yield by 10%~47%.Yields of the esters are higher than 90%.Thus,equal-molecular acetic acid and n-butanol was refluxed in perfluorous nonene at 80 ℃for 1.5 h,and the average yield of 5 runs was 98.5%.The aftertreatment was simple.The perfluorous solvents and catalyst sulfuric acid were recovered by simple phase separation and reused directly in next run.