A Merger of Relay Catalysis with Dynamic Kinetic Resolution Enables Enantioselective β-C(sp3)-H Arylation of Alcohols

Abstract

The conceptual merger of relay catalysis with dynamic kinetic resolution strategy is reported to enable regio- and enantioselective C(sp³)-H bond arylation of aliphatic alcohols, forming enantioenriched β-aryl alcohols typically with >90 : 10 enantiomeric ratios (up to 98 : 2 er) and 36-74 % yields. The starting materials bearing neighbouring stereogenic centres can be converted to either diastereomer of the β-aryl alcohol products, with >85 : 15 diastereomeric ratios determined by the catalysts. The reactions occur under mild conditions, ensuring broad compatibility, and involve readily available aryl bromides, an inorganic base, and commercial Ru- and Pd-complexes. Mechanistic experiments support the envisioned mechanism of the transformation occurring through a network of regio- and stereoselective processes operated by a coherent Ru/Pd-dual catalytic system.

Keywords: C−H bond functionalisation; dynamic kinetic resolution; enantioselective reactions; relay catalysis; transition metal catalysis.