Asymmetric transformations enabled by synergistic dual transition-metal catalysis

Abstract

From its beginnings in the Sonogashira reaction, synergistic dual transition-metal catalysis has gained increasing prominence and importance. In the past decade, this strategy has been intensively investigated in the enantioselective construction of chemical bonds and has shown an increasing number of novel transformations and yielded greater reactivity, selectivity, and efficiency than traditional mono-transition-metal catalysis. In this review, we present recent examples of asymmetric reactions enabled by synergistic dual metal catalysis to provide readers with the fundamental attributes and abilities of this concept. We discuss the mechanism, kinetics, and selectivity in detail to showcase how two distinct transition-metal complexes would work cooperatively and independently to enable challenging transformations. Asymmetric synergistic dual metal catalysis, a conceptually promising strategy in which two (or more) reactants are activated concurrently and cooperatively by distinct metal catalysts, has received increasing attention because of its ability to yield unprecedented reactivity (e.g., new bond-forming mechanism) and selectivity (e.g., regio-, chemo-, diastereo-, and enantioselectivity) toward the catalytic construction of enantiopure molecules. The key issue in designing and developing successful dual metal catalytic systems is the judicious selection of a pair of transition-metal/ligand complexes that are compatible with redox and metal-ligand coordination and dissociation, as well as have comparable kinetics—the turnover of two metallic catalysts should be near simultaneous. To enhance the understanding of current synergistic dual metal catalysis and aid in the development of related fields, this review provides a general overview of the reported types of asymmetric dual metal catalysis, their catalytic mechanisms, and the design and application of catalyst systems. In this review, Wei and Wang present recent examples of asymmetric reactions enabled by synergistic dual metal catalysis to provide readers with the fundamental attributes and abilities of this concept. They discuss the mechanism, kinetics, and selectivity in detail to showcase how two distinct transition-metal complexes would work cooperatively and independently to enable challenging transformations.