Golden times for allenes: Gold-catalyzed cycloisomerization of beta-hydroxyallenes to dihydropyrans.

The gold(I)-catalyzed 6-endo cycloisomerization of beta-hydroxyallenes provides a mild and efficient access to chiral functionalized dihydropyrans which were obtained at room temperature in good chemical yields with axis-to-center chirality transfer. The method was extended to the beta-aminoallene 12, which afforded tetrahydropyridine 13 in good yield as well.