Ester and Lactone Formation with the Reagent 1,2‐Dihydro‐4,6‐dimethyl‐2‐thioxo‐3‐pyridinecarbonitrile

Transformation of long‐chain ω‐hydroxy acids into the macrolactone can be accomplished with the title compound. The disulfied derived therefrom is esterified with the acid to give (1) ; on heating (1) gives the lactone. The thiol esters (1) are less expensive and more readily accessible than comparably reactive lactone precursors.