Hydrogen Bond-Catalyzed Synthesis of Oxazolidinone over Ionic Liquid 1-Hydroxyethyl-3-methylimidazolium Acetate

Abstract

Herein, we report a hydrogen bonding-catalyzed three-component reaction of 1,2-benzylamine, styrene oxide, and dimethyl carbonate over ionic liquid 1-hydroxyethyl-3-methylimidazolium acetate ([OH-EMIm][OAc]) to synthesize various oxazolidinones in excellent yields at 100 °C. This indicates that [OH-EMIm][OAc] can activate 1,2-benzylamine and styrene oxide through hydrogen bonding to form intermediate 2-(benzylamino)-1-phenylethan-1-ol, which further reacts with dimethyl carbonate activated by [OH-EMIm][OAc], producing oxazolidinone via intramolecular cyclization of the intermediate methyl benzyl(hydroxy(phenyl)methyl)carbamate. Moreover, [OH-EMIm][OAc] could be reused five times without loss of activity. This protocol provides a facile and novel route to oxazolidinones, which may have promising application potential.