Synthesis of Chiral Isoxazoline Derivatives by Highly Diastereoface-Selective 1,3-Dipolar Cycloaddition of Nitrile Oxides Mediated by Magnesium Bromide and Ytterbium Trifluoromethanesulfonate

In the presence of an equimolar amount of Lewis acid such as magnesium bromide and ytterbium trifluoromethanesulfonate, 1,3-dipolar cycloaddition reactions of aromatic nitrile oxides to a chiral 3-acryloyl-2-oxazolidinone gave the corresponding chiral 2-isoxazolines in a diastereoselective manner.