Studies On Cu-Catalyzed Intramolecular Hydroarylation Reactions Of Alkynes

Intramolecular hydroarylation reactions of alkynes have been demonstrated in this thesis. A series of challenging and utility polycyclic aromatic frameworks can be synthesized by this reaction. Polycyclic aromatic frameworks have been widely practical utilized in the fields of agrochemicals, Pharmaceuticals. For example, dihydronaphthalenes and chromenes derivatives are very important compounds. Pd, Pt, Au, Ru, and others precious-metal and/or poisonous catalysts catalyzed intramolecular hydroarylation reaction of alkynes have been reported in the past decades. Therefore, the development of a nontoxic and inexpensive catalyst system to complete this reaction is substantial practical interest.In this paper, We began our study by testing the intramolecular hydroarylation of 1-methoxy-4-(4-phenylbut-1-ynyl)benzene. we determined using Cu(OTf)2as catalyst, 1,2-dichloroethane or toluene as solvent at 60℃ for 4-12 h as the optimal reaction conditions after screening catalyst, solvents, temperature and time. The method employs nontoxic and inexpensive catalyst and the reaction is experimentally simple, good yield and exhibiting wide functional group tolerance and certain heteroaromatics. The further transformation of the model product can be complete very well. The results of kinetic isotope experiment suggest that the present Cu-catalyzed cyclization may proceed via a Friedel-Crafts type process.