One pot microwave-assisted synthesis of 3-benzyl-5-hydroxymethyl-1, 3-oxazolidin-2-one

Oxazolidinone is a five-member heterocyclic ring used as a privileged structure for the synthesis of ligands for different biological targets. Many synthetic approaches have been made available for oxazolidinone, however, they were found to be either time/energy consuming or multistep process. One of the approach is a one-pot method to synthesize 3-benzyl-5-hydroxymethyl-oxazolidin-2-one using reflux overnight (>12 h). The aim of the present work was to develop an improved method by the use of microwave irradiation to make 3-benzyl-5-hydroxymethyl-oxazolidin-2-one. Benzyl amine was reacted with the various carbonate salts and epichlorohydrin, in presence of bases and solvent and the reaction was carried out under open and sealed-vessel conditions. Various factors including the use of carbonate salts, base, solvent, time, temperature and power were optimized. Microwave-assisted synthesis of 3-benzyl-5-hydroxymethyl-1,3-oxazolidin-2-one gave yields of 69.59% and 77.0% in an open vessel and a closed vessel, respectively with reduction in reaction time from overnight (>12 h) to 1 h in the open vessel and to 30 min in closed vessel.