基于1,5-H迁移/环化的C-H官能化反应的机理研究

Seven-membered benzoazacyclic frameworks are widely found in natural products and pharmaceutical molecules. Nitrogen-containing heterocyclic derivatives can be directly obtained by using br?nsted acid as a catalyst, but the corresponding reaction mechanism is still unclear. In this paper, the br?nsted acid-catalyzed Pictet-Spengler reaction for the synthesis of benzoaza-skeleton derivatives was selected as the template reaction, and the reaction mechanism was studied by theoretical calculation. The theoretical calculations are consistent with the experimental reports that the introduction of different numbers of methoxy groups into the benzene ring results in different products, and the rate determining step of the reaction is all 1,5-hydride shift. In addition, the geometric structure and electrostatic potential energy surface (ESP) analysis of the key transition states and intermediates were performed to explain the cause of chemoselectivity.