微波辐射下己二酸、壬二酸双酯的无溶剂合成

Microwave -Promoted Synthesis of Di-esters of Adipic Acid and Azelaic Acid without Solvent

摘要:

在微波辐射下，用己二酸、壬二酸分别与异辛醇、正十二醇合成四种润滑油类双酯。研究结果表明：在微波辐射下催化剂用量为3.0% ～3.5%、微波功率为300 w～320 w的反应条件下己二酸双异辛酯和壬二酸双异辛酯分别在反应时间为8 min和12 min合成得到98%和99.4%的高产率；；己二酸双十二酯和壬二酸双十二酯分别在反应时间为6.5 min和7.5 min合成得到95%和97%的高产率。研究得到了二元羧酸双异辛酯和二元羧酸双十二酯微波合成的实验参数。产物的色泽和结晶点被测定，并用1H NMR、13C NMR和 IR对产物结构进行了表征。与传统合成方法比较，微波合成法将己二酸双十二酯、壬二酸双十二酯、己二酸双异辛酯和壬二酸双异辛酯产率分别提高了3%、6%、11.5%和29%，反应时间缩短了7.1～11.4倍，且产物色泽好。微波合成方法对润滑油类双酯是一种快速、高效、新的合成方法。

Abstract:

Under microwave irradiation the di-esters of lubricating oil are synthesized by the reaction of adipic acid or azelaic acid with 2-ethylhexyl alcohol or dodecanol. The results show that for catalyst amount of 3.0% ～3.5% and microwave power of 300 w～320 w the yields of di-(2-ethylhexyl)adipate and di-(2-ethylhexyl) azelate are respectively 99.4% and 98% for 12 min and 8 min, and the yields of didodecyl adipate and didodecyl azelate are respectively 97%and 95% for 6.5 min and 7.5 min. The experimental parameters of microwave synthesis for four di-esters are investigated. The chromaticity and crystallization point of di-esters are measured and their structures have been characterized by 1H NMR、13C NMR and IR spectra. Compared with conventional synthesis method, the microwave method can achieve excellent yield of 95%-～99.4% within 6.5 min -～12 min. The reaction time has a reduction by a factor of 7.1 to 11.4 and the yields of didodecyl adipate, didodecyl azelate, di-(2-ethylhexyl) adipate and di-(2-ethylhexyl) azelate are 3%, 6%, 11.5% and 29% higher than the conventional yields, respectively. Moreover, the color of products is colorless or white. Microwave synthesis method is a rapid, highly efficient and novel synthetic approach for lubrication oil di-esters.