文摘
The reaction mechanism of the gold(I)-phosphine-catalyzed hydroamination of 1,3-dienes wasanalyzed by means of density functional methods combined with polarizable continuum models. Severalmechanistic pathways for the reaction were considered and evaluated. It was found that the most favorableseries of reaction steps include the ligand substitution reaction in the catalytically active Ph3PAuOTf speciesbetween the triflate and the substrate, subsequent nucleophile attack of the N-nucleophile (benzyl carbamate)on the activated double bond, which is followed by proton transfer from the NH2 group to the unsaturatedcarbon atom. The latter step, the most striking one, was analyzed in detail, and a novel pathway involvingtautomerization of benzyl carbamate nucleophile assisted by triflate anion acting as a proton shuttle wascharacterized by the lowest barrier, which is consistent with experimental findings.