Stereoelectronic control in the solvolysis of spiroepoxidic 1-norbornyl triflates: unexpected reactivity in 3-bromomethyl derivatives

Interesting norbornane-fused tetrahydrofurans, with an additional synthetically-valuable vicinal dioxy-substitution in the norbornane skeleton, are enantiospecifically obtained in high yield from epimeric camphor-derived 3-endo-bromomethyl-substituted spiroepoxidic 1-norbornyl triflates. The process takes place via a domino reaction stereoelectronically controlled by the bromine atom. The described process has synthetic value, since it opens the way for a future enantiospecific preparation of 2,3-disubstituted tetrahydrofurans from camphor.