The Hydroboration of 1-Alkylthio-l-alkynes, and Its Application to the Syntheses ofS-Alkyl Alkanethioates and (Z)-1-Alkylthio-1-alkenes

Abstract Hydroboration of 1-alkylthio-1-alkynes with dicyclohexylborane or bis(1,2-dimethylpropyl)borane proceeded smoothly, adding most of the dialkylboryl group to the α-position of the triple bond. The resulting alkenylboranes afforded either S-alkyl alkanethioates on a controlled oxidation with alkaline hydrogen peroxide in the presence of N,N,N′,N′-etramethylethylenediamine or (Z)-1-alkylthio-1-alkenes on a basic protonolysis, successive treatments with methyllithium, copper(I) iodide and water in the presence of hexamethylphosphoric triamide.