Eco-Friendly Synthesis of Sulphonic Acid Oxime Esters Catalyzed by 2-(1<i>H</i>-Benzotriazole-1-yl)-1,1,3,3-Tetramethyluronium Tetrafluoroborate

Abstract

Herein we describle a facile synthesis of sulphonic acid oxime esters in acetonitrile from the corresponding sulphonic acids and oximes catalyzed by the environmental friendly 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU) in the presence of triethylamine (TEA) under mild conditions. The present approach offers the advantages of a clean reaction, simple methodology, employing readily available catalyst, short reaction duration, high selectivity and high yield.