Aqueous-Phase, Palladium-Catalyzed Suzuki Reactions under Mild Conditions

Yueqin Cai, Gonghua Song, Zhongyuan Wu, Jiawei Zhang

School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, China.
Shanghai Key Laboratory of Chemical Biology, Institute of Pesticides & Pharmaceuticals, East China University of Science and Technology, Shanghai, China.

DOI: 10.4236/gsc.2013.34A001                

Abstract

Water-soluble ionic liquid-supported diols have been used as phosphine-free ligands in Suzuki couplings of aryl idides/bromides/chlorides under mild conditions in aqueous solvent. It was found that 2,2-bis((1-hexylimidazolium)-mehyl) propane-1,3-diol hexafluorophosphate (4) in combination with palladium (II) salts gave the most significant catalyst. Suzuki couplings of aryl iodides/bromides occurred efficiently at room temperature in water/acetonitrile. Notably, the reactions of hydrophilic aryl bromides gave high yields in neat water. The catalyst PdCl₂-4 was recycled five times in Suzuki couplings in water before catalyst activity began to significantly drop. The average yield of five cycles was >95% per cycle.

Keywords

Suzuki Reaction; Ionic Liquid-Supported Diols; Phosphine-Free Ligands

Conflicts of Interest

The authors declare no conflicts of interest.

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