月桂酸与二甲胺合成N,N-二甲基月桂酰胺的研究

Study of synthesizing N,N-dimethyl laurylamide using lauric acid and dimethylamine

以月桂酸和二甲胺为原料,在Cu基催化剂作用下,采用高压釜反应合成N,N-二甲基月桂酰胺。研究了温度、压力、原料配比、催化剂用量和时间等对月桂酸转化率和N,N-二甲基月桂酰胺选择性的影响,并考察了升温速率对产物色泽的影响。结果表明:在180℃,2.0 MPa,n(二甲胺)∶n(月桂酸)=1.4∶1,催化剂用量为月桂酸质量的3.0%,反应时间6 h,转速600 r/min,升温速率10℃/min的优化工艺条件下,月桂酸转化率达到95.8%,N,N-二甲基月桂酰胺选择性达到98.6%,且产物色泽较淡。

N,N-dimethyl laurylamide was synthesized by the action of Cu-based catalyst in an autoclave,taking lauric acid and dimethylamine as raw materials.Effects of reaction temperature,pressure,raw material proportion,reaction time and catalyst dosage on the lauric acid conversion and laurylamide selectivity were studied,as well as the effects of heating up rate on the color of product was examined.The result indicated that under reaction temperature 180 ℃,reaction pressure 2.0 MPa,molar ratio for dimethylamine to lauric acid 1.4∶ 1,catalyst dosage 3.0%（w） of lauric acid,reaction time 6 h,rotating speed of stirrer 600 r/min and with heating up rate of 10 ℃/min,the conversion of lauric acid achieves 95.8%,the selectivity of laurylamide achieves 98.6%,and a rather light color product can be obtained.