Studies Toward Total Synthesis Of Ovafolinin B

This thesis focuses on the total synthesis of lignan ovafolinin B.It consists of the following three chapters.Chapter 1: This chapter introduces the progress of 1,4-conjugate addition with the emergence of some new ligands and new metal catalysis systems in recent years.At the same time,this chapter demonstrates synthetic applications of 1,4-conjugate addition.Chapter 2: This chapter begins with a brief discussion of total synthesis of lignan Ovafolinin B by other groups.Then we introduce our synthetic exploration of this molecule,in which nickel-catalyzed reductive cyclization could be used as a key reaction.However,the elongation of the carbon chain has encountered obstacles,and I am trying to solve this problem.Asymmetric synthesis of Ovafolinin B was also tried,which used 1,4-conjugate addition induced by the chiral auxiliary group to construct the diaryl methine center.However,problems still existed in the attempted addition of the aromatic nucleophile.Chapter 3: This chapter introduces the synthetic study of indene-type compounds using reductive nickel catalysis developed by our laboratory.Optimization of reaction conditions for intramolecular coupling catalyzed by nickel was shown in detail.