Suzuki cross-coupling reactions over Pd(II)-hydrotalcite catalysts in water

We studied the Suzuki cross-coupling reaction between bromobenzene and phenylboronic acid at room temperature in aqueous media containing K2CO3 as the base and solids consisting of Pd(II) supported on an Mg/Al hydrotalcite as catalysts. Based on the results, a surfactant facilitating the dissolution of phenylboronic acid in water is required for the reaction to develop at room temperature. Sodium dodecylsulphate proved the most effective surfactant among those tested for this purpose, which included anionic, cationic and neutral compounds. The conversion and selectivity results were excellent and on a par with previously reported values. However, ICP-MS measurements of palladium content before and after the reaction revealed that some metal in the catalyst was dissolved, so the catalytic process was not completely heterogeneous; rather, the reaction involves substantial homogeneous catalysis.

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