Selenothioic acid S-alkyl esters were synthesized from the reaction of terminal acetylenes with n-butyllithium, selenium, and alkanethiols in moderate to high yields. The use of substituted benzenethiols or (triphenylsilyl)acetylene allowed for the isolation of S-aryl esters. The synthesis of α-aryl selenothioic acid S-alkyl esters was attained by the acid-catalyzed reaction of selenoacetic acid Se-alkynyl