Researches On Visible-Light Photoredox Catalyzed Minisci Reactions

Although minisci reactions playing a crucial role in C-H functionalization of N-heteroarenes have been discovered for almost half a hundred year,their obviously disadvantages such as harsh reaction conditions and low production efficiency limit their wide applications in organic synthesis.In recent years,because visible-light photoredox catalysis charactered by mild reaction conditions,safety and high production efficiency has developed rapidly,it is of great significance to catalyze Minisci reactions by visible-light photoredox catalysis.Here we accomplished our studies about visible-light photoredox catalyzed Minisci reactions and achieved research results.This paper displaying our research results was divided into three parts showed as follows:Chapter Ⅰ:Mechanisms of visible-light photoredox catalysis and early-stage developments of Minisci reactions.In the first part of this chapter,we detailly illustrated mechanisms of visible-light photoredox catalysis by taking the common photocatalyst,Ru（bpy）₃²⁺,as an example.Furthermore,we summarized photocatalyst category and briefly explained two mechanism study experiments.In the second part,we detailedly introduced the early-stage development history of Minisci reactions and briefly described polar effects and medical applications of Minisci reactions.Chapter Ⅱ:Researches on Minisci alkylation via visible-light photoredox catalysis.At the beginning of our work,reports about Minisci alkylation reaction in past decade were reviewed,and then we found that compared with other prefuntionlized alkylation reagents,bromoalkanes charactered by available preparation are ideal alkyl radical precursors.However,in traditional Minisci reactions,as bromoalkanes are difficult to activate,we need to strictly control reaction conditions.Herein,we achieved Minisci alkylation reaction of heteroarenes（i.e.,isoquinoline）via phototredox catalysis under mild condition using bromoalkanes as alkyl radical precursors.Chapter Ⅲ:Researches on Minisci aroylation via visible-light photoredox catalysis.At the beginning of this work,we reviewed reports about Minisci aroylations reaction in the past decade and applications of acyl chlorides in photoredox catalysis.Our investigation results demonstrated that although acyl chlorides were frequently used as acylation reagents,there were no reports,as far as we know,about Minisci acylation using acyl chlorides as radical sources.Herein,we describe a new strategy for Minisci aroylation employing aroyl chlorides as acyl radical precuesors for the first time via visible-light photoredox catalysis.