catalytic asymmetric 1,3-dipolarcycloaddition of pyruvate-derived nitrones to α,β-unsaturatedaldehydes was investigated in the presence of various chiral amines. Highly functionalized isoxazolidines containing a quaternary stereocenter were obtained in moderate yields with up to 92% ee. To the best of our knowledge, this is the first example of an enantioselective1,3-dipolarcycloaddition of ketonitrones