A facile synthesis of isoxazolo[3,4-a]pyrrolizine and isoxazolo[4,3-c]pyridine derivatives via intramolecular nitrone cycloaddition reaction

Abstract

A facile and efficient protocol for the construction of isoxazolo[3,4-a]pyrrolizine and isoxazolo[4,3-c]pyridine derivatives through in situ formation of nitrone ylide followed by an intramolecular [3 + 2] cycloaddition reaction is described. This reaction paved the pathway way for the successful assembly of angularly substituted cyclic heterocycles, which creates two new rings, three contiguous stereocenters and one tetra substituted carbon center in a highly diastereoselective fashion with good yields.