Reaction Mechanism of 2-Propynyl-Aniline with Propyne

Abstract

The reaction mechanism of 2-propynyl-aniline with propyne catalyzed by AuCl3 has been studied by the B3PW91 method with the LANL2DZ effective core potential and basis set for gold, and 6-31G* and 6-311++G** basis set for C,H,O,Cl. The calculated results show that the reaction occurred through eight steps. The hydrogen migration step with the highest activation free energy of 198.13 kJ/mol is the rate determining step. The catalyst is easy to detach from the product with an activation of free energy of 48.83 kJ/mol. In addition, although the reaction has a relative high activation free energy, it can smoothly yield the indole derivatives because it is a strong exothermic reaction of 418.60 kJ/mol.