Site-Selective C-H alkylation of Complex Arenes by a Two-Step Aryl Thianthrenation-Reductive Alkylation Sequence
Beatrice Lansbergen1, Paola Granatino1, Tobias Ritter1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, D-45470 Mülheim an der Ruhr, Germany.
Abstract:
Herein, we present an undirected para-selective two-step C-H alkylation of complex arenes useful for late-stage functionalization. The combination of a site-selective C-H thianthrenation with palladium-catalyzed reductive electrophile cross-coupling grants access to a diverse range of synthetically useful alkylated arenes which cannot be accessed otherwise with comparable selectivity, diversity, and practicality. The robustness of this transformation is further demonstrated by thianthrenium-based reductive coupling of two complex fragments.
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