An Efficient and One-pot Procedure for the Synthesis of Chiral Isoxazolidine via Catalytic Highly Enantioselective 1,3-dipolar cycloaddition

Synthesis of enantiomerically pure isoxazolidine via an asymmetric 1,3- dipolar cycloaddition reaction of nitrone with electron-deficient dipolarophile was described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendate bis(imine)–Cu(II)triflate complex as catalyst. The reaction mechanism is discussed on the basis of the assignment of the absolute configuration of the cycloadducts.