Mixed phosphine/N-heterocyclic carbene palladium complexes: synthesis, characterization and catalytic use in aqueous Suzuki-Miyaura reactions

作者：Schmid Thibault E; Jones Dale C; Songis Olivier; Diebolt Olivier; Furst Marc R L; Slawin Alexandra M Z; Cazin Catherine S J^*

来源：Dalton Transactions, 2013, 42(20): 7345-7353.

DOI：10.1039/c2dt32858e

A series of N-heterocyclic carbene (NHC)/PR3 palladium(II) and palladium(0) complexes has been synthesized and fully characterized. X-ray crystallographic data have allowed comparison of ligand steric properties. The NHC ligand was found to vary its steric properties as a function of the phosphine co-ligand. These complexes display interesting catalytic properties in the Suzuki-Miyaura reaction performed in aqueous media. The pre-catalyst [PdCl2(IPr)(XPhos)] (IPr = N,N%26apos;-bis-(2,6-diisopropylphenyl)imidazol-2-ylidene; XPhos = 2-dicyclohexylphosphino-2%26apos;,4%26apos;,6%26apos;-triisopropylbiphenyl) was found to be the most efficient system, promoting the coupling of a wide range of aryl chlorides with boronic acids in aqueous media with a typical catalyst loading of 0.03 mol%.

• 出版日期2013