Cross-coupling Reaction of Aryl Grignard Reagents with Aromatic Halides catalyzed by Bis (acetylacetonato) nickel (II)

Abstract

A series of cross-coupling reactions of aryl Grignard reagents with aromatic iodides catalyzed by bis (acetylacetonato) nickel (II) was studied to establish reaction conditions under which the cross-coupling proceeded selectively and quantitatively. Under the standard conditions thus selected, the coupling reactions proceeded within a few hours by a simple procedure and gave very pure product in high yield. Thus, the Kharash-type cross-coupling reaction was found to be very useful for the synthesis of a variety of polyphenyls. With some reactants of more or less orowded geometry, the reaction resulted in rather low yields of polyphenyls. This cross-coupling was successfully applied to the synthesis of a new compound, 2, 6, 2', 6'-tetraphenylbiphenyl, having a highly non-planar arrangement of π-systems.