The synthesis of mono- and bicyclic ethers via acid catalysed ring-openingcyclisation of tetrahydropyranyl ether derivatives

A range of monocyclic and bicyclic alkenols were synthesised via acid catal ysed ring-opening cyclisation of homoallylic tetrahydropyranyl ether deriva tives in excellent yield. Upon palladium catalysed hydrogenation these prod ucts were reduced with excellent diastereoselectivity to the corresponding saturated cyclic alcohols in essentially quantitative yield.