The reaction of arenesulfonyl iodides with alkynols generally provides adducts in good yields. Treatment of these adducts with KN (SiMe3) 2 gives enol ethers; cyclisation of the functionalised pentenol (5) results in formation of the exo-alkylidene tetrahydrofuran (7), whereas the homologous hexenol (6) gives the dihydropyran (8). Attempts to cyclise the hexenol (6) with potassium t-butoxide under the conditions reported by Short and Ziegler ...
