Copper-catalyzed Synthesis Of The Quinazolinone And Quinzaoline Qeribatives

Quinazolinone and quinazoline derivatives are abundant in nature,and they often exist in natural products.A variety of the reports regarding synthetic of quinazolinone and quinazoline derivatives have been presented due to their chemical and biological interests.In this thesis,our researches focus on the preparation of quinazolinone and quinazoline derivatives via Ullmann coupling reaction,and some important results were obtained as follows:A new and highly efficient method was developed for synthesis of quinazolinone derivatives via copper-catalyzed coupling reactions of 2-halobenzoic acid derivatives with guanidines.After the optimization process of catalysts,bases and solvents,the protocol uses 20 mol%CuI as catalysts,Cs₂CO₃ as base and DMF as solvent.A series of2-amino-4?3H?-quinazolinone derivatives were synthesized in good yields without the addition of a ligand or an additive.A possible formation mechanism of 2-amino-4?3H?-quinazolinone derivatives was proposed.This method is economical and practical,providing an opportunity for the construction of diverse and useful molecules in organic and medicinal chemistry.A new and convenient approach was developed for synthesis of quinazoline derivatives via copper-catalyzed coupling reactions of 2-bromobenzaldehyde or2-bromophenylketones with guanidines.The protocol uses 20 mol%CuI as catalysts,40mol%L-proline as ligand,Cs₂CO₃ as base and DMF as solvent.A series of2-aminoquinazoline derivatives were synthesized in good yields under mild conditions.This method is of important application values for construction of N-heterocycles in organic chemistry and medicinal chemistry.