Asymmetric Organocatalyzed Intermolecular Functionalization of Cyclohexanone-Derived Dienones.

Over the past decades, the advent of asymmetric organocatalysis has changed the way chemists think about creating or breaking chemical bonds, enabling new enantioselective strategies for functionalized molecules. The success of asymmetric organocatalysis is notably based on the existence of various activation modes, leading to countless transformations, and on the vast array of available chiral organic catalysts. Breakthroughs in this area have also been driven by selective functionalization of compounds with multiple activation sites such as cyclohexanone-derived dienones. These platforms can undergo diverse transformations such as Michael addition, Friedel-Crafts alkylation or Diels-Alder cycloaddition that offer new opportunities for reaching natural products and biologically relevant compounds. Amongst cyclohexanone-derived dienones, the 2,5-cyclohexadienone motif has received a great deal of attention due to its reactivity pattern and recently, (cross)-conjugated cyclohexanone-derived substrates have also been considered. In this review, we discuss the intermolecular functionalization of (cross)-conjugated cyclohexanone-derived compounds employing asymmetric organocatalysis.