Computational interpretation of the stereoselectivity for a dirhodium tetracarboxylate-catalyzed amidation reaction

A catalytic cycle of a dirhodium tetracarboxylate (diRh) catalyzed intramolecular amidation reaction was investigated with density functional calculations, and the stereoselectivity of the amidation product was successfully interpreted. The product selectivity was calculated from the free energy of activations for four different reaction pathways. The pathway that forms cis-stereomer on the singlet potential energy surface has the lowest free energy of activation in the four pathways examined. The results may provide deeper insight into transition-metal catalyzed C-N bond formation reactions, as well as help synthetic chemists better design/select the catalyst ligands and the reactant substrates for this type of reaction. (C) 2010 Elsevier B.V. All rights reserved.