三甲苯麝香合成新工艺的研究

Study on New Process of Synthesizing Musk Tibetene

介绍了以炼油厂催化重整的C9重芳烃中的连三甲苯为起始原料经叔丁基化、混酸硝化两步法制备三甲苯麝香的新工艺,实验得出了优化工艺参数。采用高效液相色谱来测定三甲苯麝香的含量,并通过熔点测定、元素分析、核磁共振谱以及红外光谱等手段对三甲苯麝香产品进行了表征。以连三甲苯计三甲苯麝香的总收率达到45%(mol),三甲苯麝香的纯度达到99%以上。连三甲苯两步法合成三甲苯麝香的工艺简单、原料价格便宜、产品收率高,有较好的工业应用前景。

New process for preparing musk tibetene from 1,2,3-trimethylbenzene by tert-butylation and nitration is described. The best technological parameters of each reaction were as following:in tert-butylation[5], the molar ratio of 1,2,3-trimethylbenzene to 2-chloro-iso-butane was 1:1, the mass ratio of W100 catalyst (home-made, heterogeneous) to 1,2,3-trimethylbenzene was 1:50, reaction temperature was 5 ℃, reaction time was 7h. 5-tert-butyl-1, 2, 3-trimthyl-benzene intermediate was separated by distillation under vacuum. In nitration, with nitro-sulfuric acid(95% fuming nitric acid, 98% concentrated sulfuric acid) as nitration agent, the molar ratio of nitric acid to intermediate was 2.73:1, the molar ratio of sulfuric acid to intermediate was 3.73:1, the mass ratio of stabilizing agent urea to nitric acid was 1:100, reaction temperature was 20→60℃(2h at 20℃, 5h at 60℃) and reaction time was 7h. Musk tibetene was purified by recrystallization with 95% alcohol. The composition of product was analyzed by HPLC. Through melting point test, elementary analysis, NMR and FTIR, the constitutional formula of product was proved to be musk tibetene. New process had many advantages such as simple procedure, shorter reaction period, cheaper raw material, higher yield, etc. So the process had good prospect for industrialization.