Au(I) and Au(III)-Catalyzed Mechanism of the Cyclization Reaction of 3-(Ethynylamino)-1,3-diphenylprop-2-en-1-one

Resumo

The mechanisms of the cyclization reaction of 3-(ethynylamino)-1,3-diphenyl-2-en-1-one catalyzed by AuCl and AuCl₃ catalysts were studied using the density functional theory based on the M06 and B3LYP functionals combined with the 6-31G(d,p), 6-311++G(d,p), LANL2TZ) basis sets. The results show that the reaction can occur through one pathway containing four processes to yield the final product both with AuCl and AuCl₃ catalysts. The energy barrier of the rate-determining step of the reaction with AuCl, hydrogen transferring process, is 18.22 kJ mol^–1 lower than that of the reaction with AuCl₃. And the energy barrier of the catalysts depriving from the product with AuCl is 58.11 kJ mol^–1 lower than that with AuCl₃. These results indicate that the catalytic activity of AuCl is better than that of AuCl₃ for this type of reactions. The results of this study can be a theoretical reference in selecting a suitable catalyst for this type of reactions.