Configured droplet reactor by Pd/g-C3N4 for the Suzuki-Miyaura cross-coupling reaction under water condition

The Pd-catalyzed Suzuki-Miyaura coupling reaction is a crucial tool for constructing C−C bonds. Currently, the organic solvents employed during reaction may cause serious environmental problems. Moreover, the low solubility of inorganic bases in organic solvents leads to enormous mass transfer resistance. To address this issue, the Pickering droplets reactor stabilized by Pd/g-C₃N₄ at substrate-water two-phase interface is reported. Benefiting from the hydrophobic conjugated framework and hydrophilic terminal groups, Pd/g-C₃N₄ can configure stable Pickering emulsion without additional functionalization. The Pd loaded catalysts exhibits excellent performance (TOF = 21852 h⁻¹) for the Suzuki-Miyaura coupling reaction, which is deriving from unique electronic structure of g-C₃N₄ and high interfacial area of emulsion. Moreover, there is no clear decrease in reactivity after six cycles (conversion >86%). In this study, the organic solvent was replaced by reaction substrate, and the high activity can be achieved for various halogenated aromatic hydrocarbons and their derivatives.