Chelation enforcing a dual gold configuration in the catalytic hydroxyphenoxylation of alkynes

The functionalization of alkynes by Au (N-heterocyclic carbene, NHC) complexes via the hydrophenoxylation reaction is a paradigm for the discussion between mono and dual metal catalysis. With the aim of mimicking the framework containing two gold units, achieved with molecular boxes, two NHC ligands were joined here with a chelated chain and this motif was examined in the hydrophenoxylation/hydroalkoxylation reactions through DFT calculations. This synthetic motif transforms the standard hydrophenoxylation intermolecular reaction from an inter- into an intra-molecular nucleophilic attack, when forming the C-O bond. Various chain lengths were tested with regard to the coordination of the alkyne to the cationic NHC-gold(I) center.

Automated summary

The functionalization of alkynes by Au (N-heterocyclic carbene, NHC) complexes through hydrophenoxylation reaction is a topic of discussion for mono and dual metal catalysis. This study examined a synthetic motif that mimics a framework with two gold units and tested its role in hydrophenoxylation/hydroalkoxylation reactions using DFT calculations. Different chain lengths were explored in terms of coordinating the alkyne to the cationic NHC-gold(I) center.