A New Iron-Catalyzed Aluminum Variant of the Negishi Coupling

Significance Herein, the first example of an iron-catalyzed Negishi-style cross-coupling of arylaluminum reagents and alkyl bromides is described. The highest conversions are obtained when FeCl 2 (dppbz) 2 is used as catalyst. To obtain the arylaluminum compounds, the transmetalation of arylmagnesium species with AlCl 3 is the best route. The presence of magnesium salts in the ­reaction mixture is crucial for the success of this reaction, as salt-free triarylaluminum reagents do not react well under these conditions.