Mohadeseh Goli - School of Chemistry, Damghan University, Damghan, Iran
Hamzeh Kiyani - School of Chemistry, Damghan University, Damghan, Iran

Organosulfonic acids demonstrate an important generation of organocatalysts in organic synthesis,which have been successfully applied in different types of acid-catalyzed organictransformations [1]. Isoxazole and its derivatives are good synthetic targets on account oftheir important applications, including pharmaceutical functions in medicine as antimicrobial,antiviral, anticancer, anti-inflammatory, immunomodulatory, anticonvulsant or anti-diabeticagents, pest control in agriculture, and also convertible to other heterocyclic compoundsthrough catalytic processes [2]. Multi-component reactions (MCRs) are one of the most syntheticallyareas in modern organic synthesis for the synthesis of high levels of molecular diversityfrom three or more substrates with a minimal number of operations. Some obviousadvantages of MCRs include atom-, and step-economy, cost-effectiveness, no need for isolationof intermediates, and manufacture of heterocyclic compounds with high diversity in onesynthetic step. These characteristics together with the associated reduction of waste make agreener alternative to multistep synthesis [3]. In the present work, catalytic amounts of 2-benzyl-1-sulfopyridin-1-ium have been used for the synthesis of isoxazol-5(4H)-ones througha MCR procedure. This eco-friendly, one-pot, three-component process was performed usingethyl acetoacetate, various aromatic aldehydes, and hydroxylamine hydrochloride as reactants,and above-mentioned catalyst under aqueous conditions (Fig. 1). The heterocyclicproducts were obtained in good to excellent yields and relatively shorter reaction times.