Study On The Synthesis Technology Of Roseoxide And The Chiral Resolution Of β-citronellol

My dissertation consists of two parts.The study on synthesis technology of rose oxide is the first part. Rose oxide (I) is a major natural fragrance compound. There are a lot of methods can be used to prepare rose oxide, but few can be used to industrial manufacture. In this paper, three step reactions were used to synthesize rose oxide, which involved oxidation, reduction and cyclization. In the first two steps, the3,7-dimethyl-oct-5-en-1,7-diol (II) and3,7-dimethyl-oct-7-en-1,6-diol (III) are prepared from β-citronellol. Finally, the rose oxide (I) was cyclized from (II) with acidic catalyst. In this paper, dosage of hydrogen peroxide, molar ratio, type and dosage of catalyst, reaction temperature and reaction duration were optimized. Under optimized conditions, the yields of mixed diols (II and III) and rose oxide (I) are95%and41.5%respectively, and the total yield is39.4%. And according to the repeated experiments results, the industrial design has been accomplished.The second part is the chiral separation of citronellol. Citronellol is one of important monoterpenes spices. We found that there is little information about the synthesis of chiral citronellol. So the kinetic resolution of Citronellol in organic phase, catalyzed by lipse, was investigated. Trough screening lipases, lipase Noxozym435was found, which show higher activity and better enantioselectivity for the resolution of Citronellol. The optimal reaction conditions were finally achieved by further investigating the effects of solvents, temperature, rotation speed and enzyme concentrations, and so on. Under optimal conditions,61.1%ee value of S-(-)-citronellyl acetate and the selectivity is up to7.2, while the enzyme can be reused six times.