A gas-phase study of the gold-catalyzed coupling of alkynes and alcohols

Mass spectrometric methods are used for an investigation of the C-O bond formation between alkynes and alcohols mediated by cationic gold(l) complexes. In the condensed-phase catalysis, an efficient coupling to the corresponding enol ethers has been observed. In the gas phase, however, kinetic and entropic restrictions are too large for both bare Au+ as well as (CH3)(3)PAu+ to permit bond formation in strictly bimolecular collisions occurring at thermal energies. The experimental findings are complemented by a theoretical study of the Au+/C2H2/CH3OH system using density functional theory. (c) 2005 Elsevier B.V. All rights reserved.