Fatty acids. part 42 The preparation and properties of methyl monomercaptostearates. some related thiols, and some methyl epithiostearates

Some saturated and unsaturated mercapto C₁₈ esters have been obtained for the first time. Such compounds are prepared from hydroxy esters via their mesyloxy derivatives by reaction with sodium hydrogen sulphide or with potassium thioacetate (followed by deacetylation) or from alkene esters by radical addition of thioacetic acid. The mercapto esters are readily identified by infrared, nuclear magnetic resonance, and mass spectroscopic procedures, preferably after acetylation or trifluoroacetylation.γ-Mesyloxy alkenes furnish tetrahydrothiophen rather than mercapto alkenes and methyl 9,12-epithiostearate was synthesised by an independent route from thiophen.