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

by Sílvia Escayola, Jordi Poater, Miguel Ramos, Luigi Cavallo, et.al.
Year: 2021 DOI: https://doi.org/10.1002/aoc.6362

Extra Information

Appl Organomet Chem.

Abstract

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.