Cross-scale integratable catalytic stirrer for aqueous-phase organic synthesis

Abstract

Although aqueous-phase reactions are an environmentally friendly approach to organic synthesis, their effectiveness is limited by the inefficiency of coupling immiscible mass transfer with surface reactions. Here, we present a cross-scale, integratable catalytic stirrer that reduces this limitation by employing a synthesis strategy that intensifies the process. We demonstrate the stirrer’s effectiveness by using the hydrogenation of nitrobenzene in an aqueous phase as a model system. Production rates increase significantly under extremely mild conditions—by 26.7 and 9.7 times in water using hydrazine hydrate and H2 as hydrogen donors, respectively, compared to traditional hydrogenation in organic solvents using a powder catalyst. This strategy can be extended to synthesize a wide spectrum of amines (78 examples, 12 of which are drug intermediates), alkanes (9 examples) and alcohols (8 examples). We anticipate that our design strategy will facilitate the development of advanced systems that integrate catalysts and devices for significant yet challenging aqueous-phase transformations in multiphasic systems.