Studies Toward Synthesis Of Conosilane A Skeleton

This thesisi mainly discussesd a synthetic process of the skeleton of sesquiterpenoid Conosilane A,which was described in the following two chapters.The first chapter introduced the research progress of atom transfer radical reactions in recent years from chemists at home and abroad,especially focusing on types of catalyst used in the research process.The development trend of catalyst for atom transfer radical reactions,which is from the initial peroxide,organotin reagents to the transition-metal reagent and later organic light catalyst,was also presented the research progress of atom transfer radical reactions.In chapter 2,the isolation,bioactivities,biosynthesis of sesquiterpene and the complete synthesis of the Conosilane A by other research group were briefly introduced.After that,we mainly discussed the use of the Ni-catalyzed tandem cyclization reaction developed by our research group to try to construct the 6-5-5tricyclic carbon skeleton of this nature product.Since the traditional Ni-catalyzed tandem cyclization reaction could not afford the desired carbon skeleton smoothly,the subsequent reaction could not be carried out.Therefore,a preliminary attempt using the photo-nickel dual catalytic system was made to construct the tricyclic carbon skeleton structure of this molecule,although the experimental work failed to get the target compound.After that,we redesigned a more convergent synthetic route.Although different cyclization precursors were prepared and the corresponding reaction conditions were also optimized,disappointedly,the expected cyclization product was still not obtained.