The reaction mechanism of incorporation of carbon dioxide into o-alkynylaniline derivatives catalyzed by silver salt

We investigated a DFT study on the reaction mechanism of CO2 and alkynylaniline derivative. Three reaction systems have been studied for comparison, with no catalyst, silver salt catalyst and copper salt catalyst, respectively. The results indicate that the reaction catalyzed by silver salt in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) is the optimal path and it involves two parts: the transfer of hydrogen, the insertion of CO2 molecule. In this path, silver salt can reduce the whole energy of the system, and DBU makes the hydrogen transfer more easily. Moreover, all the energy barriers of this path are very low, so that it is more likely for the reaction to proceed at normal temperatures and pressures.