Functionalization of Sulfonic Acid to Sulfonic Ester Using Diazo Compound under Mild Reaction Conditions in the Absence of Additives

Abstract Sulfonate esters are important owing to their special bioactivities. Nevertheless, severe reaction conditions, use of expensive catalysts along with additives and the numerous side reactions in the previously reported methods demand the development of valid approaches for the synthesis of aryl sulfonate esters. Herein, we report a facile synthetic strategy utilizing the V IV based catalyst for the carbene insertion into the O−H bond of sulfonic acids to afford sulfonate esters up to 90 % yield under mild reaction conditions. All the synthesized sulfonate esters were fully characterized by using standard spectroscopic and analytical techniques such as NMR, IR, ESI‐MS and single crystal XRD analysis.