Thionyl Chloride-Mediated One-Pot <i>O</i> -, <i>N</i> -, and <i>S</i> -Deacetylation and Esterification of a Diverse Series of Acetoxy, Acetamido, and Thioacetate Carboxylic Acids

Thionyl chloride (SOCl₂) has been extensively used as a chlorinating reagent for the esterification of carboxylic acids via the formation of an acid chloride intermediate. While SOCl₂-mediated deacetylation of acetoxy (<i>O</i>-deacetylation) and acetamido (<i>N</i>-deacetylation) esters is rare and has been reported on a coumarin substrate, deacetylation of thioacetate (<i>S</i>-deacetylation) esters by SOCl₂ is unknown. Furthermore, a simultaneous deacetylation and esterification of acetoxy, acetamido, and thioacetate carboxylic acids in a one-pot synthetic scheme has not been reported in the literature. We report deacetylation and esterification of a diverse series of acetoxy carboxylic acids mediated by SOCl_2, with examples from acetamido and thioacetate carboxylic acids to obtain hydroxy, amino, and thiol esters in a one-pot procedure. The reaction can be conveniently carried out at room temperature for 8-18 h, followed by an aqueous workup in good to excellent yields and has a very broad substrate scope.