Thionation of esters and lactones with the reagent combination of phosphorus pentasulfide and hexamethyldisiloxane

The combination of P4S10 and hexamethyldisiloxane converts esters and lactones to thionoesters and thionolactones in yields comparable to or superior to those obtained with Lawessonʹs reagent. The method has the advantage that reagent-derived byproducts may be removed by a simple hydrolytic workup or by filtration through silica gel, rather than by chromatography, as required for Lawessonʹs reagent.