Diastereoselective Synthesis of Novel Spiro-Isoxazolidines via [3 + 2] Cycloaddition.

In this protocol, synthesis of novel 2,5-diphenyl-3,3-spiropentamethylene-5H-2,3,3a,6a-tetrahydropyrrolo[3,4-d]isoxazole-4,6-diones through [3 + 2] cycloaddition of N-cyclohexylidene N-phenyl nitrones with cyclic dipolarophiles is described. 1,3-Dipolar cycloaddition of nitrones with substituted N-arylmaleimides gives exclusivelyendo-diastereoisomers of spiro-isoxazolidines and their stereochemistry was assigned using1H NMR and1H-1H correlation spectroscopic studies. [ABSTRACT FROM AUTHOR]