Surface-functionalized mesoporous nanoparticles as heterogeneous supports to transfer bifunctional catalysts into organic solvents for tandem catalysis

The combination of chemo- and biocatalysts offers a powerful platform to address synthetic challenges in chemistry, particularly in synthetic cascades. However, transferring both catalysts into organic solvents remains technically difficult because of the enzyme inactivation and catalyst precipitation. Herein, we designed a facile approach using functionalized mesoporous silica nanoparticles (MSN) to transfer chemo- and biocatalysts into a variety of organic solvents. As a proof-of-concept, two distinct catalysts, palladium nanoparticles (Pd NPs) and Candida antarctica lipase B (CalB), were stepwise loaded into separate locations of the mesoporous structure, which not only provided catalysts with heterogeneous supports for the recycling but also avoided their mutual inactivation. Moreover, mesoporous particles were hydrophobized by surface alkylation, resulting in a tailor-made particle hydrophobicity, which allowed bifunctional catalysts to be dispersed in eight organic solvents. Eventually, these attractive material properties provided the MSN-based bifunctional catalysts with remarkable catalytic performance for cascade reaction synthesizing benzyl hexanoate in toluene. With a broader perspective, the success of this study opens new avenues in the field of multifunctional catalysts where a plethora of other chemo- and biocatalysts can be incorporated into surface-functionalized materials ranging from soft matters to porous networks for synthetic purposes in organic solvents.