Multicatalysis – Pushing the boundaries beyond multi-disciplinarities

Introduction
The emergence of catalysis has had a transformative impact in many fields, including the production of chemicals, healthcare, materials, agriculture and in the environmental sector. Historically, catalysts were first developed to enhance the performance of known reactions, but later catalysis started enabling new transformations to address new challenges. Today, catalytic processes produce almost 90% of the chemical industry (1) products.
Driven by the demand for more efficient and sustainable chemical processes, and bringing solutions for more complex molecules, the field of catalysis continues to evolve rapidly.
Recently, there has been a growing interest in developing multi-catalytic systems, which are inspired by the complexity of catalytic reactions occurring in nature. Indeed, synthetic chemists try to mimic the efficient metabolic networks in living organisms to build complex molecules by combining different types of catalysts in the same reaction vessel. These multistep cascade processes provide many advantages to synthetic procedures, resulting in higher productivities with lower waste generation and cost.
As illustrated in this article, multi-catalysis emerges not only to enlarge the avenue of new methodologies but also to offer potential new valuable short-cuts to the synthetic practitioner.
Within multi-catalytic processes, either multiple catalysts execute single reactions, or precise sequences of multiple catalytic reactions occur in a ‘one-pot’ fashion. Special emphasis is dedicated to the integration of several catalysts from different fields, such as chemocatalysis and biocatalysis.

The classification of multi-catalytic systems refers to some key criteria (2):