Synergistic catalysis, a type of plural catalysis which utilizes at least two different catalysts to enable a reaction between two separately activated substrates, has unlocked a plethora of previously unattainable transformations and novel chemical reactivity. Despite the appreciable utility of synergistic catalysis, specific examples involving two transition metals have been limited, as ensuring a judicious choice of reaction parameters to prevent deactivation of catalysts, undesirable monocatalytic event(s) leading to side products, or premature termination and other potentially troublesome outcomes present a formidable challenge. Excluding those driven by photocatalytic mechanisms, this review will highlight the reported examples of reactions that make use of two simultaneous catalytic cycles driven by two transition metal catalysts.

A mild and efficient synthesis of N-arylcarbamates was achieved by reacting azidoformates with boronic acids in the presence of 10 mol % of copper chloride catalyst. The reaction proceeds readily in an open flask at room temperature without additional base, ligand, or additive. Rapid access to urea analogues via a two-step one-pot procedure is enabled by reacting N-arylcarbamates with aluminum-amine complexes. In addition, among several boronic acid derivatives prepared, dimethylphenyl boronate was found to react rapidly in its reaction with benzyl azidoformate, invoking in situ generation of this species in the catalytic cycle.

Reported is a tandem palladium‐catalyzed Heck/regioselective C(sp3)−H activation reaction for the divergent synthesis of spiro‐ and fused‐cyclopropanated indolines from N‐methallylated 2‐bromoarylamides. The regioselectivity of the C−H bond activation in the σ‐alkylPdII intermediate is controlled by the solvent used. DFT calculations suggest that the polarity of solvent molecules could influence the transition‐state energy, leading to a bifurcation of the C−H bond activation in the σ‐alkylPdII intermediate.

An efficient method for the synthesis of ketones using organolithium and acid chlorides under continuous flow conditions has been developed.