The Synthesis And Phytophthora Citralis Nitrile Mating Hormone Synthesis

With the development of green chemistry and resource chemistry, our group hasinvented an efficient and environment-friendly method to degrade steroidalsapogenins with hydrogen peroxide. Therefore optically pure chiral segments arereadily obtained from the residue of degradation of steroidal sapongenins, which havebeen transformed to stable building blocks with chiral methyl center and then are usedfor synthesis of various target molecules with stereogenic centers bearing methylgroups.Our synthetic targets are bioactive natural products and their analogues, and those thatcan be made using these chiral building blocks as starting materials. This thesis willcover the following two parts.1（R）-Citralis Nitrile^? has been synthesized from （2R,4R）-5-（（tert-butyldimethyl-silyl）oxy）-4-methylpentane-1,2-diol, with dehydroxylation by Raney Ni in neutralreaction condition as a key step. And the total yield is up to80.7%for6steps.（S）-Citralis Nitrile^? has been synthesized from the same starting material above, withCu-catalyzed cross coupling as a key step. And the total yield is up to83.4%for6steps.2Three different synthetic routes have been explored to synthesize C6-C16fragment of Phytophthora Mating Hormone α1and α2, which are based on adivergent strategy by using different stable building blocks with chiral methyl group.Hydroxyl-directed addition as the key step to construct the right confirmation of chiraltertiary alcohol has been conducted.