Theoretical study on Au(I)-catalyzed [2 + 2 + 2] cycloadditions of ynamides with two discrete nitriles

The Au-catalyzed [2 + 2 + 2] cycloadditions of ynamides with two discrete nitriles were theoretically studied with the aid of DFT calculations. The reaction under consideration is found to start from binding of the catalyst with the ynamide rather than with the nitrile. The Au(I)–ynamide species (1) can effectively induce dimerization of two nitrile molecules while the catalyst only cannot. The Au(I)–ynamide species (1) is revealed to be more reactive than the Au(I)–nitrile species (2). Also, the regioselectivity and the influence of EWG vs. EDG involved in the reaction were also rationalized.