Studies on the Lewis acid catalyzed synthesis of isoxazolidin-3-ones

The reaction of α, β-epoxy esters with N-alkyl-1-phenylmethanimine oxides in the presence of a Lewis acid was explored in this study. A substrate sustained-release strategy was successfully employed to overcome the inherent conflict between substrate activation and catalyst poisoning, allowing for the efficient synthesis of a variety of substituted isoxazolidin-3-ones. The reaction employs inexpensive and readily available starting materials, proceeds under mild conditions, and demonstrates broad substrate compatibility. Moreover, when chiral epoxy substrates were used, the products were obtained with high retention of enantiomeric purity.