Preparation method for tetradecyl methyldihydroxyethyl ammonium bromide

The invention discloses a preparation method for tetradecyl methyldihydroxyethyl ammonium bromide. The method includes the steps of: mixing bromotetradecane with N-methyldiethanolamine according to a mole ratio of 1:1, dissolving the mixture in n-pentanol, conducting reflux reaction in microwave, at the end of reaction, adding an ethanol-ethyl acetate mixed solvent into the reaction solution to crystallize the product so as to obtain a white solid; and during reflux, always maintaining continuous action of microwave and boiling of the reaction solution. Compared with traditional methods, the method provided by the invention has enhanced target product conversion rate, and the required reaction time is 27% of that of the traditional methods.