Methylaluminoxane as an Alternative for BArF in the Iridium-Catalyzed Asymmetric Hydrogenation of Imines

Authors

  • Dr. Nataša Mršić,

    1. Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
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  • Dr. Lavinia Panella,

    1. DSM Innovative Synthesis B.V., a unit of DSM Pharma Chemicals, P.O. Box 18, 6160 MD Geleen (The Netherlands), Fax: (+31) 46-4767604
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  • Edwin G. IJpeij,

    1. DSM Innovative Synthesis B.V., a unit of DSM Pharma Chemicals, P.O. Box 18, 6160 MD Geleen (The Netherlands), Fax: (+31) 46-4767604
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  • Prof. Dr. Adriaan J. Minnaard,

    Corresponding author
    1. Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
    • Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
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  • Prof. Dr. Ben L. Feringa,

    Corresponding author
    1. Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
    • Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
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  • Prof. Dr. Johannes G. de Vries

    Corresponding author
    1. Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
    2. DSM Innovative Synthesis B.V., a unit of DSM Pharma Chemicals, P.O. Box 18, 6160 MD Geleen (The Netherlands), Fax: (+31) 46-4767604
    • Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen (The Netherlands), Fax: (+31) 50-3634296
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Abstract

original image

An ionic revolution? BArF has been the anion of choice for iridium-catalyzed imine hydrogenation; however, for large-scale production its use may be too costly. Methylaluminoxane (MAO) can be used instead in conjunction with [{Ir(COD)Cl}2], although enantioselectivities are somewhat lower than with BArF if 50–500 eq. of MAO are used.

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