Anti-addition mechanism in the intramolecular hydroalkoxylation of alkenes catalyzed by PVP-stabilized nanogold.

(1R*,4S*,4aR*,9aS*,10S*)-10-Hydroxy-10-phenyl-1,4a,9a,10-tetrahydro-1,4-methanoanthracen-9(4H)-one (1c) was prepared for the elucidation of the reaction mechanism of intramolecular hydroalkoxylation of alkenes catalyzed by gold nanoclusters stabilized by a hydrophilic polymer, poly(N-vinyl-2-pyrrolidone) (Au:PVP). It was found that the reaction proceeded via anti-addition of alcohol to the alkene assisted by p-activation of the gold clusters, which is the same mechanism as the hydroamination by toluenesulfonamides.