Johan Van der Eycken,Timothy Noël, Katrien Bert and Pieter Janssens

Laboratory for Organic and Bioorganic Synthesis, Department of Organic Chemistry, Ghent University, Krijgslaan 281 (S.4), B-9000 Ghent, Belgium

Abstract:

Nitrogen-containing ligands are known as cheap, readily accessible and stable alternatives for phosphane ligands [1], which are often very sensitive to air and require a multistep synthesis [2].  We wish to present a combinatorial approach to a novel type of nitrogen-based mono- and bidentate ligands [3]. These ligands are characterized by their modular structure, allowing an easy one-step synthesis by simply combining two readily variable precursors which are either commercially available, or can be reached in only a few steps: a cyclic imidate 1 and a (chiral) amine, respectively diamine. These ligands show promising results in e.g. the Cu(I)-catalyzed asymmetric aziridination of methyl cinnamate, in asymmetric diethylzinc additions to benzaldehydes, in the Pd(0)-catalyzed asymmetric allylic alkylation and amination, and in Ir(I)-based asymmetric hydrogenation of alkenes, and hence are promising tools for medicinal chemistry.

References
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[3]        (a) Noël, T.; Vandyck, K.; Robeyns, K.; Van Meervelt, L.; Van der Eycken, J. Tetrahedron 29, 65, 8879-8884; (b) Noël, T.; Robeyns, K.; Van Meervelt, L.; Van der Eycken, E.; Van der Eycken, J. Tetrahedron: Asymmetry 29, 2, 1962-1968; (c) Noël, T.; Bert, K.; Van der Eycken, E.; Van der Eycken, J. Eur. J. Org. Chem. 2010, 21, 4056-4061; (d) Bert, K.; Noël, T.; Kimpe, W.; Goeman, J.L.; Van der Eycken, J. Org. Biomol. Chem., 2012, 10, 8539-8550.