Decarbonylation Reaction Promoted By Phtoredox Catalysis

The cleavage of C-C bonds by transition metal centres plays an important rolein the functionalization of hydrocarbons and in the synthesis of complex orgnicmolecular from biomass and petroleum feedstocks. Compared with the cleavage ofC-H bonds, the cleavage of C-C bonds is much more difficult attributed to kineticand thermodynamic factors. Starting materials with special functional groups orharsh reaction conditions such as high temperature or pressure were used to facili-tate it. In this thesis, efficient carbon-carbon bond cleavage with unactive fragmentsas leaving group promoted by phtoredox catalysis(Ru(II)) afford to ketone deriva-tives.At first2-(2-oxo-2-phenylethyl)cyclopentanecarbaldehyde was choosed as thestandard substrate to optimize reaction condition. as a result,2-(2-oxo-2-phenyleth-yl)cyclopentanone was formed up to95%in GC conversion detection in the condi-tion of5mol%(Ru(bpy)3Cl2.6H2O),3equivalentiPr2NH as coupling partners inCH3CN,45W lamp as light source.The scope and generality of this decarbonylation reaction of nonactivated al-dehyde was explored.18substrate aldehydes containing α-hydrogen were synthe-sized and cyclopentaneformaldehyde derivatives and α-aryl formaldehyde performbetter than other substrate under the optimized reaction conditions and achievemore than80%conversion.On the basis of the observations, we propose the mechanism of enamine singleelectron transfer reaction.All the target compounds were characterized by NMR and HRMS analysis.