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In this study, a set of enantiomerically pure aziridines bearing a phosphine oxide moiety were prepared in high yields and tested as chiral catalysts in the direct asymmetric Mannich reaction of hydroxyacetone, an amine (p-anisidine), and various aromatic aldehydes. The appropriate Mannich adducts were formed in chemical yields from moderate to good with a high level of enantio- and diastereoselectivity. The best results were obtained using the catalysts bearing a free NH-aziridine subunit.

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The isomerization of (Z)‐1,4‐diacetoxy‐2‐butene (1) catalyzed by PdCl2(MeCN)2 was studied in THF and DMF. The reaction occurs more rapidly in THF than in DMF, but in both solvents it did not proceed to complete consumption of the substrate and led to a mixture of 1, (E)‐1,4‐diacetoxy‐2‐butene (2), and 1,2‐diacetoxy‐3‐butene (3). The formation of 2 is more favored in DMF than in THF. The reactivity of 1 and the solvent effect differ strongly from those previously obtained with Pd(PPh3)4 as the catalyst. Interpretations are provided for the crucial role of the nature of both solvent and intermediates on the course of the isomerizations.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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Over the course of the present studies, a series of optically pure phosphines functionalized by chiral aziridines was synthesized in reasonable/good chemical yields. Their catalytic activity was checked in the enantioselective Friedel–Crafts alkylation of indoles by β-nitrostyrene in the presence of a copper(I) trifluoromethanesulfonate benzene complex. The corresponding Friedel–Crafts products were achieved efficiently in terms of chemical yield and enantioselectivity (up to 85% in some cases).