title: Synthesis and structural characterization of stable organogold(I) compounds. Evidence for the mechanism of gold-catalyzed cyclizations.
abstract: The vast majority of homogeneous Au-catalyzed reactions have exploited the propensity of Au to activate unsaturated carbon-carbon bonds as electrophiles. It is generally assumed that a nucleophile attacks a gold-activated carbon-carbon multiple bond to give an alkenyl Au intermediate, notwithstanding the fact that these intermediates are hitherto unknown. We have obtained room temperature stable gamma-lactone gold(I) complexes through the reaction of cationic Au(I) reagents with allenoates, under mild conditions. The reactions of one such complex with electrophiles yielded the expected products of Au-catalyzed cyclizations. These results furnish experimental evidence for the mechanism of Au-catalyzed cyclizations.
authors.affiliation: Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, USA.
authors.forename: Le-Ping
authors.initials: LP
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Xu
authors.forename: Mark S
authors.initials: MS
authors.lastname: Mashuta
authors.forename: Gerald B
authors.initials: GB
authors.lastname: Hammond