Abstract The intramolecular carbolithiation of a series of propargylic ethers has been performed to evaluate the influence of the terminal substituent on the efficiency and the stereochemical outcome of the cyclization. Our results show that only 5-exo-dig cyclizations are observed, and dihydrobenzofurans are obtained exclusively. Depending on the nature of the terminal substituent, two cases can be considered. If the terminal substituent carried ...
