Highly Exo-Selective Epoxidation and Hydroxylation of Triquinacene and Its Derivatives: all-exo-Hexahydroxytriquinane.

Epoxidation of triquinacene 3 with dimethyldioxirane proceeded with a high degree of exo-face selectivity to give a quantitative yield of a 1:1.5 mixture of all-exo-4a and endo,exo,exo-triepoxytriquinane 4b. Subsequent lithium aluminum hydride reduction of the all-exo-triepoxide 4a gave all-exo-2,5,8-5a and all-exo-2,5,9-trihydroxytriquinane 5b, respectively.