Palladium-catalyzed homocoupling and cross-coupling reactions of aryl halides in poly(ethylene glycol).
The direct coupling of aryl halides to prepare symmetrical and unsymmetrical biaryls were performed successfully in poly(ethylene glycol) (PEG) using Pd(OAc)2 as the catalyst in the absence of other additives or reductants. The selectivity toward biaryl depended on the amount of PEG used. Excessive PEGs induce the increase of hydrodehalogenation product, and the best selectivity to biaryl is obtained when the concentration of the hydroxyl group in PEG achieves 100 mol % relative to aryl halides. The catalyst system could be recycled and reused up to five times with no loss of catalytic activity.
Wang
Liang
L
Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China.
Zhang
Yuhong
Y
Liu
Leifang
L
Wang
Yanguang
Y
D002384:Catalysis; D003432:Cross-Linking Reagents / Q000737:chemistry*; D006846:Hydrocarbons, Halogenated / Q000737:chemistry*; D007462:Iodobenzenes / Q000737:chemistry; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*
D003432:Cross-Linking Reagents; D006846:Hydrocarbons, Halogenated; D007462:Iodobenzenes; D011092:Polyethylene Glycols; D010165:Palladium; C031905:iodobenzene