Study On The Construction Of 3,1-Benzoxazine By Scandium Trifluoromethanesulfonate Catalyzed MPVO Cyclization Reaction

Benzoxazine are a class of important heterocyclic compounds with a wide range of biological activities and material properties.In medicine,they have a variety of pharmacological activities,such as bactericidal,fungicidal,microbicidal,anti-tumor,anti-HIV and anti-inflammatory;and it is an important raw material for the synthesis of polybenzoxazine.In recent years,chemists have tried new methods to synthesize the compound and made great progress.Different methods have been developed to construct Benzoxazine compounds containing halogen,alkyl and sulfur.However,2-aminobenzyl alcohol and aldehyde ketones are usually used under harsh conditions.Therefore,it is very important to develop other direct and effective ways to prepare benzoxazine compounds.This thesis mainly includes two chapters: the first chapter summarizes the research progress of MPVO reaction.It mainly includes the MPVO reactions catalyzed by metal aluminum,lanthanide metals,transition metals,other main group metals,and other non-metal catalytic systems,and MPVO cascade reactions.In the second chapter,we have achieved the first direct and efficient preparation of a series of Benzoxazines by MPVO cascade reaction catalyzed by Scandium trifluoromethanesulfonate.The reaction conditions are mild,the experimental operation is simple,and the applicability of the substrate is wide.Finally,a series of 4-H-3,1-Benzoxazine compounds were synthesized with excellent yields.