Preparation Of Secondary Amine Via Reductive Alkylation Process From Ketone And Primary Amine

The dehydration,condensation and reduction of aldehyde/ketone and amine to prepare advanced amine is an important organic reaction,which has been widely used in synthesizing a variety of amines.In this thesis,the reductive alkylation of ketone and primary amine to synthesize secondary amine was investigated.Taking the reductive alkylation of N-phenyl-p-phenylenediamine(RT base)and methyl isobutyl ketone(MIBK)to N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine(rubber antioxidant 4020)as the probe reaction,we studied one-step and two-step synthesis processes.The one-step process was achieved by the direct synthesis of 4020 from RT base and MIBK in the presence of Pd/C catalyst treated with sulfide.Despite the method is simple,it has many drawbacks such as lower convention of raw materials at low reaction temperature and unstability of catalyst at high reaction temperature.Therefore,we improved the one-step process and proposed a two-step preparation method,i.e.,firstly the formation of imine from RT base and MIBK,and then the hydrogenation of imine to 4020.We selected the catalysts used for preparing secondary amine and optimized the synthesis conditions.The results showed that the co-utilization of activated carbon and molcular sieve was the most effective and resulted in better activity and selectivity.The test of catalyst-stability suggested that the catalyst exhibited good stability during the reactions.In the case of catalytic hydrogenation of imine on Pd/C treated by Ph2S,the effects of the content of sulfurization agent as well as different loadings of Pd on the yield product were discussed.The reaction conditions were also optimized to obtain 4020 with high convention and selectivity successfully.The Pd-S/C catalyst with 10%loading of Pd under the optimum reaction conditions of 160?,3.0 MPa,6 h,the convention of raw materials and the selectivity of target product could reach 100%and 97%,respectively.After the reaction finished,Pd-S/C could be regenerated by simple sulfide treatment.The regenerated catalyst could be reclaimed for forteen recycles without loss of activity.