A new enantioselective Michael addition between 3-(3-hydroxy-1-pyrazol-1-yl)oxindole, a new synthon generated from isatin ,-cyclic azomethine imine 1,3-dipole, and β-nitrostyrene has been disclosed. A series of chiral 3-(3-oxo-2,3-dihydro-1-pyrazol-1-yl) disubstituted oxindoles were obtained in excellent results (up to 97% yield, up to 94% ee) with moderate to good diastereoselectivities (up to 4.3:1 dr).

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http://dx.doi.org/10.1021/acs.joc.9b03337DOI Listing

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