Gold-catalyzed intermolecular hydroalkoxylation of allenes; difference in mechanism between hydroalkoxylation and hydroamination

A wide range of alcohols 2 react with various allenes 1 in the presence of ClAuPPh3/AgOTf catalyst at ambient temperature without solvent to produce allylic ethers 3. Contrary to the hydroamination, which proceeds through high chiral-face selectivity for chiral allenes to give the corresponding chiral allylic amines, transfer of chirality is not observed in the hydroalkoxylation, suggesting that the mechanism of the gold-catalyzed hydroalkoxylation is different from that of hydroamination. (C) 2008 Elsevier Ltd. All rights reserved.