Photocatalytic Synthesis Of Fused Pyran Compounds And Quinazolinone Derivatives

In recent years,visible light photoredox catalysis has become an important area of the organic synthesis,as it is environmentally friendly,highly efficient,and operationally simple,etc.In a general sense,these approaches rely on the ability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single-electron transfer with organic substrates,thereby generating reactive intermediates.The chemistry of fused pyran compounds and quinazolinone derivatives synthesis and functional group transformation has attracted interests from organic chemists because these moieties exists in natural products and drugs.In this dissertation,we have introduced the latest development of visible light catalysis,and we have developed visiblelight-induced reactions to synthesize fused pyran compounds and quinazolinone derivatives.This dissertation is divided into three parts:Part I: This chapter described the recent advances of visible-light photoredox catalysis in organic synthesis and summarized the work of the relevant research group in the field.Part II: This chapter firstly described the research progress of organic cascade reactions with 1,7-enynes as substrate.Then,we developed a visible-light-catalyzed cascade reaction: synthesis of fused pyran derivatives via visible-light-induced cascade cyclization of 1,7-enynes with acyl chlorides.Finally,we studied the mechanism of acyl radical formation using fluorescence quenching techniques and an electrochemical method.Part III: This chapter firstly described the research progress of organic reactions with 1,2,3-benzotriazinones as substrate and the utility of triplet sensitization by energy transfer in organic photochemistry.Then,we present a method for the efficient synthesis of quinazoline derivatives by visible light catalysis.Finally,we proposed a plausible reaction mechanism to describe this transformation.