Synthesis of N , N-Dimethyl-N′-lauryl-1 , 3-propanediamine and Its Homologues with Boric Acid Catalyst

N,N-Dimethyl-N′-lauryl-1,3-propanediamine and its homologues were synthesized from different kinds of fatty acids and N,N-dimethyl-1,3-propanediamine(DMAPA).By changing the reaction temperature,adjusting the mole ratio of fatty acid and N,N-dimethyl-1,3-propanediamine and adding different proportions of boric acid,the optimal reaction of the amidation reaction were oftained,which were as follows:n(fatty acids)∶n(DMAPA)=1∶1.8,the amount of boric acid 5mol%,reacting temperature of 110℃and reaction time of 6to 8h.The yield was 78%～90%.The product was characterized by IR spectroscopy.