Sustainability concerns are the wind in the sails for the development of novel, more selective catalytic processes. Hence, chiral catalysts play a crucial role in the green production of enantioenriched compounds. To further increase the green profile of this approach, the use of solid-supported catalytic species is appealing due to the reduced generation of waste, as well as the possibility of reusing the precious catalyst. Even more attractive is the implementation of flow processes based on these immobilized catalysts, a flexible strategy that allows to generate from milli- to multi-gram amounts of chiral product with a reduced footprint set-up. Herein, we will present the efforts devoted in our laboratory towards the immobilization of chiral catalysts and their use in single-pass, highly enantioselective, flow processes. Proline, diarylprolinols, other aminocatalysts, squaramides, thioureas, phosphoric acids and even chiral ligands and metal-based catalysts constitute our current toolkit of supported species for enantioselective catalysis.
Catalytic Enantioselective Flow Processes with Solid-Supported Chiral Catalysts
Chem Rec. 2019, 19 (9), 1872-1890, DOI: 10.1002/tcr.201800097.