Abstract In reactions of (alkylthio) fluorobenzenes with n-butyllithium the compounds 4-RSC 6 H 4 F (R= Me, i Pr) and 2-i PrSC 6 H 4 F were found to undergo metalation selectively ortho to the fluorine atom, whereas 2-MeSC 6 H 4 F undergoes metalation at the thiomethyl carbon atom.