Modular Synthesis of Optically Active Tröger’s Base Analogues

Abstract

For the first time, enantioselective catalysis was applied for the preparation of Tröger's base derivatives affording N-stereogenic building blocks not only in excellent enantiomeric purity but also in an easily scalable fashion. Enzymatic kinetic resolution proved efficient to yield functionalized Tröger's bases, which can be subsequently modified by various chemical methods without any erosion of stereogenic information. In concert with a preparatively convenient protocol for the synthesis of the racemic substrates from commercially available anilines, a highly practicable and flexible route towards a wide range of enantiopure Tröger's base analogues is provided.