Organic Synthesis Reaction Based On Enaminone Carbon-hydrogen And Carbon-carbon Bond Functionalization

As the most basic and common chemical bonds and structural units in nature,C-H and C-C bonds exist widely in various organic compounds.It is a very important synthetic strategy to construct new chemical bonds by directly functionalizing C-H and C-C bonds.Enaminones are a class of intermediates chemicals in organic synthesis,and are widely used in the synthesis of various organic molecules because of their enriched reaction sites and high reactivity.This thesis is devoted to the synthesis of diffierent molecules via the conversion of enaminones C-H and C-C bonds.Three main sections of research work are included.In the first section,we developed a method for synthesizing trifluoromethylsulfonylated enaminones based on enaminones α-C-H trifluoromethylsulfonylation.By employing N,N-disubstituted enaminones and sodium trifluoromethanesulfinate as reaction substrates,and iodine was as a promoter in media of mixed acetonitrile and dimethylsulfoxide,the synthesis of trifluoromethylsulfonylated enaminones was achieved.In addition,under the same system,the synthese of difluoromethylsulfonylated and pentafluoroethylsulfonylated enaminones were also achieved.In the second section,we explored and realized the synthesis of 3-trifluoromethylchromones and 3-trifluoromethylpyrimidines.By using potassium persulfate as an oxidant,the o-hydroxyphenyl functionalized N,N-disubstituted enaminones and cheap sodium trifluoromethylsulfinate reacted effciently to provide 3-trifluoromethylchromones.The trifluoromethylpyrimidines were successfully synthesized using these chromones to react with amidines under the promotion of potassium carbonate.In the third section,we realized the synthesis of α-ketoester by enaminones C=C double bond α-oxoesterification via transition metal-free photocatalysis.A green photocatalytic system using Rose Bengal as a photocatalyst and glacial acetic acid as a promoter was established for the reation of N,N-disubstituted enaminones and alcohols.On this basis of this transfomation,adding o-phenylenediamine to the finished reaction system enabled the one-pot,two-step synthesis of quinoxalinone compounds.