Multicomponent Synthesis Of α-substituted α,β-unsaturated Ketones Based On Electrophile Intercepted Meyer-Schuster Rearrangement

α-substituted α,β-unsaturated ketones have important biomedical applications.Although there are many synthesis ways,a simple and fast method without metal catalyst is still needed to be further studied.Therefore,a new method for the synthesis of α-substituted α,β-unsaturated ketones is developed in this paper.The main work of this paper is to achieve the construction of α-substituted α,β-unsaturated ketones by blocking the Meyer-Schuster rearrangement of propargyl alcohol with electrophilic reagent.The first part of the study is the synthesis of α-aminomethyl α,β-unsaturated ketone from three components of aryl propargyl alcohol,sulfonamide and aldehyde catalyzed by trifluoromethanesulfonic acid as electrophilic reagents.The second part is the synthesis of α-alkoxy-methyl α,β-unsaturated ketone from acetal as electrophilic reagent,aryl proparylene alcohol catalyzed by silver trifluoromesylate,aldehyde protective reagent and aldehyde three components.Both electrophiles do not need to be prepared separately and are generated directly from commercial raw materials in situ during the reaction process to avoid excessive reaction steps that affect the reaction rate and yield.This method provides a new method for the synthesis of α-substituted α,β unsaturated ketones.This method is a multi-component one-pot reaction,which has the advantages of easy availability of catalyst,simple operation,high utilization rate of atoms,wide range of substrate application and low reaction cost.