Unveiling the complexity of the dual gold(I) catalyzed intermolecular hydroamination of alkynes leading to vinylazoles

Abstract

The conversion of alkynes into functionalised alkenes catalyzed by Au(NHC) complexes (NHC = N-heterocyclic carbene) is a fundamental and atom-economical transformation yet its mechanistic understanding is limited. In order to shed light on such catalytic reaction mechanisms, computational tools are utilized to gain insights into the gold catalyzed intermolecular hydroamination of internal alkynes. The combination of alkynes and benzotriazole leads to vinylazoles via a solvent free, gold(I) mediated hydroamination. DFT permits an in-depth discussion of single versus dual metal catalysis in this transformation. The role of the triflate anion is studied, being essential for the protodeauration and it helped to clarify the rate determining step, that consists of the gold-tiazolyl nucleophilic attack to the gold-alkyne π-complex