Overcoming the Incompatibility Challenge in Chemoenzymatic and Multi-Catalytic Cascade Reactions.

Multi-catalytic cascade reactions bear a great potential to minimize downstream and purification steps, leading to a drastic reduction of the produced waste. In many examples, the compatibility of chemo- and biocatalytic steps could be easily achieved. Problems associated with the incompatibility of the catalysts and their reactions, however, are very frequent. Cascade-like reactions can hardly occur in this way. One possible solution to combine, in principle, incompatible chemo- and biocatalytic reactions is the defined control of the microenvironment by compartmentalization or scaffolding. Current methods for the control of the microenvironment of biocatalysts go far beyond classical enzyme immobilization and are thus believed to be very promising tools to overcome incompatibility issues and to facilitate the synthetic application of cascade reactions. In this Minireview, we will summarize recent synthetic examples of (chemo)enzymatic cascade reactions and outline promising methods for their spatial control either by using bio-derived or synthetic systems.