Surprising obtention of an enantiopure eight-membered cyclic ether from camphor

A highly-functionalized eight-membered cyclic ether, with an additional interesting trans-fusion to a cyclobutane ring, is enantiospecifically obtained in high yield from a camphor-derived di(spiroepoxide)-substituted 1-norbornyl triflate, via a regio- and stereocontrolled domino process. The described process could constitute a novel model procedure for the preparation of eight-membered cyclic ethers from α,α′-bis(spiroepoxide) cyclopentyl derivatives.