Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reaction...Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reactions of aryl bromides and iodides with very high turnover numbers (ca. 103–104).展开更多
The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported...The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.展开更多
Water-soluble diol-functionalized imidazolium ionic liquid 1, prepared from 2,2-bis（1-methyl-methyl-imida- zolium）propane-l,3-diol bromide, potassium hydroxide, and malononitrile, was used as an efficient phosphine-...Water-soluble diol-functionalized imidazolium ionic liquid 1, prepared from 2,2-bis（1-methyl-methyl-imida- zolium）propane-l,3-diol bromide, potassium hydroxide, and malononitrile, was used as an efficient phosphine-free ligand for palladium-catalyzed arylation of aryl halides with acrylates in aqueous phase under mild conditions. It was found that the synergistic coordinating action of diol-functionalized imidazolium cation with CN-containing anion played the key role in improving the activity and stability of the catalyst.展开更多
文摘Some 1,3-dicarbonyl compounds (such as pentane-2,4-dione and 3-oxo-N-phenylbutanamide) were found to constitute highly efficient, yet low-priced and phosphine-free ligands for the Pd-catalyzed Heck and Suzuki reactions of aryl bromides and iodides with very high turnover numbers (ca. 103–104).
基金Acknowledgement We acknowledge the Natural Science Foundation of China （Grant 20676033）, China Postdoctoral Science Foundation （Grant 20070410169） and Shanghai Leading Academic Discipline Project （Project Number： B507） for financial support.
文摘The coordination mode of IL-supported diols used as phosphine-free ligands for palladium catalyzed Heck reaction has been investigated by tuning their compositions. The difference in coordination of these IL-supported diols with metal Pd in Heck reaction was related to the changes of the cation rings, leading to the different activities of Pd catalyst in the reaction. The experimental results indicated that the activities of Pd catalyst were affected mainly by n-electron density of the cation rings. Compared to pyridinium and piperidinium cations, imidazolium cations showed the best coordination to metal Pd. In the meantime, C-2 hydrogen and the length of alkyl side chains had impacts on the coordination as well.
基金the National Natural Science Foundation of China （No. 20676033）, the China Post- doctoral Science Foundation （No. 20070410169） and the Shanghai Leading Academic Discipline Project （No. B507） for financial support.
文摘Water-soluble diol-functionalized imidazolium ionic liquid 1, prepared from 2,2-bis（1-methyl-methyl-imida- zolium）propane-l,3-diol bromide, potassium hydroxide, and malononitrile, was used as an efficient phosphine-free ligand for palladium-catalyzed arylation of aryl halides with acrylates in aqueous phase under mild conditions. It was found that the synergistic coordinating action of diol-functionalized imidazolium cation with CN-containing anion played the key role in improving the activity and stability of the catalyst.
