Charge-tagged polar phosphine ligands in Pd-catalysed reactions in aqueous and ionic media

TETRAHEDRON LETTERS

卷:59

Article

van Zyl, Vivien L.¹  Muller, Alfred¹  Williams, D. Bradley G.^1,2 

[1] Univ Johannesburg, Dept Chem, POB 524, ZA-2006 Auckland Pk, South Africa

[2] Univ Technol Sydney, Sch Math & Phys Sci, POB 123, Sydney, NSW 2007, Australia

关键词: Palladium;    Homogeneous catalyst;    Ionic liquid;    Ligand;   

DOI  :  10.1016/j.tetlet.2018.01.073

来源: Elsevier

【 摘 要 】

A new range of polar imidazolium and phosphate-containing ligands was synthesised from readily available starting materials in high yielding multi-step transformations. These ligands were used to generate Pd catalysts for Suzuki and Heck C-C coupling reactions in organic and organic/aqueous media. The catalysts performed well in aqueous media in the Suzuki reaction and less well in the Heck reaction, related to substrate solubility in the aqueous media. When moving to ionic liquids, the Heck reaction dramatically improved, especially in media compatible with the polar catalysts and the non-polar reagents. In all cases, the catalysts were stable to the formation of Pd black, a form of degradation that frequently befalls Pd catalysts. The catalysts could be successfully recycled without loss of activity. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

Free