Highly Efficient Asymmetric [3+2] Cycloaddition Promoted by Chiral Aziridine-Functionalized Organophosphorus
Julia Szymańska1,2, Michał Rachwalski1, Adam M Pieczonka1
1Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, PL-91-403 Lodz, Poland.
Abstract:
The asymmetric [3+2] cycloaddition of azomethine ylides generated from the corresponding imino ester-to-trans-β-nitrostyrene catalysis by chiral aziridine-containing phosphines and phosphine oxides is described. Of the sixteen stereoisomers that could be formed as a result of the title reaction, three were formed, two of which were obtained in an enantiomerically enriched or pure form, and one in a racemic form. One of the products underwent epimerization under basic reaction conditions.
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