Studies On Total Syntheses Of Calyciphylline D, Calyciphylline F, Caldaphnidine M And Organocatalyzed Tandem Reactions

This dissertation is mainly divided into three parts. The first part is a review of organocatalysis. The second part is the studies on the total syntheses of Daphniphyllum alkaloids Calyciphylline D, Calyciphylline F and Caldaphnidine M. The third part is a methodological study of organocatalyzed tandem cyclization to build a multi-substituted five-membered carbocyclic compounds.In the first chapter, we briefly review the history and the overview of organocatalysis, and systematically introduces the research progress of organocatalysis in organic methodology and total synthesis applications.In the second chapter, we designed a synthetic route which used a cationic cyclization reaction as a key step. Using adivergent synthetic strategy, we conducted a preliminary exploration on the total synthesis of Daphniphyllum alkaloids Calyciphylline D, Calyciphylline F and Caldaphnidine M.In the third chapter, we studied on a organocatalyzed asymmetric Michael addition/Aldol tandem reaction to build multi-substituted five-membered carbocyclic compounds. Through a large number of screening tests and reasonable theoretical analysis, we initially ruled out the unreasonable strategies and conditions, and reasonably speculate the cause of failure in early attempt. Then we proposed a solution which applied a multistep One-pot reaction, and conducted a large number of attempts. Finally, we completed a preliminary exploration of the new method to build multi-substituted five-membered carbocyclic compounds.