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  • Publication
    Accès libre
    Synthesis of Calix[4]pyrrolidine, Calix[m]tetrahydrofuran[n]pyrrolidine (m+n=4) and similar macrocyclic systems - elucidation of the hydrogenation sequence and factors influencing the stereoselectivity
    The first meso-octaalkylporphyrinogen (calix[4]pyrrole) was synthesized by Baeyer more than 120 years ago, mixing pyrrole and acetone in the presence of an acid. We have performed a thorough study of the catalytic hydrogenation of calix[4]pyrrole 1, by using common as well as novel heterogeneous catalysts based on transition metals (Pd, Rh, Ru) supported on solid matrices. Another investigation concerning the hydrogenation reaction was performed using twelve different macrocyclic substrates. Different factors were tested, which might influence the stereoselectivity during the hydrogenation process and therefore the number of diastereomers obtained. One of the macrocycles synthesized, offers interesting perspectives for the development of novel catalysts. In this context, we investigated the reactivity and the modification of this macrocycle. A thorough study of the nucleophilic properties and a kinetic study allow the discovery the factors that influence the reactivity of these macrocycles.