Study On Synthesis Of Magnolol

Magnolol is one of the main effective components of Magnolia which is one of the most famous and precious Chinese traditional medicine. Magnolol has comprehensive pharmacological action such as antioxidation, sedation of central nervous system, muscle relaxation and anti-ulcer action. It has an obvious activity and a wide application prospect. So far, the study for Magnolol concentrates on such factors: pharmacological study, planting, identifying and plantchemistry. The report of synthesis method is not much and the yield is low. So study on synthesis of Magnolol is very important.In this paper, magnolol was synthesized from anisole as the raw material via bromination, grignard reaction, allylation, undo-methyl reaction and oxidative coupling reaction. In designed route, the step of experimental operation is simplified and some problems reported in literature such as low yield and low purity in the course of synthesis, isolation and purified are avoided. At the same time, the reaction condition was optimized.The optimal reaction conditions (dosage ratio, temperature, time, yield) were as follows. Bromination ( the mol ratio of anisole, KBr, H₂O₂ and ammonium molybdate was 1:1.1:1.1:0.013, room temperature, 40min, 98%); grignard reaction and allylation (the mol ratio of 4-bromoanisole, Et₂O, Mg and propenyl bromine was 1:4.0:5.5:1.3, reflux, 3.5h, the total yield of the two steps was 85%); undo-methyl reaction ( the mol ratio of 4-allylanisol, AlCl₃ and ethanethiol was 1:1.2:1.1, room temperature, 3.5h, 95%); oxidative coupling reaction ( the mol ratio of chavicol, AlCl₃ and DDQ was 1:1.55:0.73, room temperature, 1.5h, 79%). The melting point of the product was the same as those reported in literatures, and the structure of the target product was affirmed by TLC and IR.