| Officinal Magnolia belong to Magnoliaceae, whose bark is used for traditional Chinese medicines. As the three-medicine management of the national plan of musk, is one of the important medicine ingredients with anti-inflammatory, antibacterial, anti-oxidation, anti-tumor, suppression of morphine withdrawal, and other pharmacological effects. Although Chinese distribution of Officinal Magnolia is broad, market prices are also most expensive with large market demand. Generally, Magnolol is separated and purified from Chinese herbal medicine by such method as thermal extraction with ethanol or petroleum ether as solvent. Magnolol from organic synthesis will help protect the ecological environment with less impact of the season and market demand. In the paper, the research work about synthesis of Magnolol and 2,2'-hydroquinone derivatives have been done, especially about the route involving grignard reaction and oxidation coupling reactions. The result will be benefitful for industrialization of Magnolol.With 4-bromophenol as raw material, 4-Bromophenol methoxy methyl ether is obtained by reaction of methoxymethyl chloride with Crude yield 89.3%. Grignard reagents is prepared from reaction of 4-bromophenol methoxy methyl ether with allyl bromide. Alllylphenol is gained from the acid solutions with yield up to Crude 65.5%. Finally, Magnolol is achieved with yield to 71% from alllylphenol with TMEDA as oxidation coupling reactor. The structure was confirmed by IR and 1HNMR and HPLC analysis. Some reaction conditions were optimized.In this paper, we also obtained 5,5′-dimethyl-2,2′-dihydroxy diphenyl, 3,3′-dimethoxy- 2,2′-dihydroxy diphenyl and 5,5′-Dibromo-2,2′-dihydroxy-biphenyl by oxidation coupling reactions. Their structure was confirmed by IR and 1HNMR. The result suggest that oxidation coupling reaction prone to occur with more electronics in the benzene ring, Other synthesis route of Magnolol is also discussed from research work about oxidation coupling reactions. |
PDF Full Text Request