Biswas, S., and D. Weix. Mechanism and Selectivity in Nickel-Catalyzed Cross-Electrophile Coupling of Aryl Halides With Alkyl Halides. J. Am. Chem. Soc., 2007.
|Abstract||The direct cross-coupling of two different electrophiles, such as an aryl halide with an alkyl halide, offers many advantages over conventional cross-coupling methods that require a carbon nucleophile. Despite its promise as a versatile synthetic strategy, a limited understanding of the mechanism and origin of cross selectivity has hindered progress in reaction development and design. Herein, we shed light on the mechanism for the nickel-catalyzed cross-electrophile coupling of aryl halides with alkyl halides and demonstrate that the selectivity arises from an unusual catalytic cycle that combines both polar and radical steps to form the new C-C bond.|
|Keywords||aromatic halides, carbon bond formation, complexes, direct arylation, functionalized grignard-reagents, ketone formation, organic halides, oxidative addition, radical catalysis, reductive conjugate addition|