Heterometallic complexes, tandem catalysis and catalytic cooperativity

This minireview reports the most recent advances in the use of heterometallic catalysts based on single-frame N-heterocyclic carbene ligands. The article describes the synthetic strategies for the preparation of heterometallic catalysts, and their applications in the design of tandem processes by combining the catalytic properties associated with the two (or more) different metal centers. Several examples are discussed in which the use of heterometallic complexes results in a clear enhancement of the catalytic outcome compared to the results provided by mixtures of related homometallic complexes. The field constitutes a research area that is full of potential and is at its very earliest stage.