10.1055/s-0033-1339653
The research investigates the catalytic activity of amido pincer nickel complexes in the Kumada cross-coupling reaction, aiming to explore effective catalyst systems for C–Cl bond activation and to probe the structural effects on catalytic activity. The study found that amido pincer nickel complexes with [4,5]-fused nickel rings, such as {Ni(Cl)[2P(Ph2)C6H4NC(Ph)=NAr]} (Ar = 4-MeC6H4, 1; Ar = 4-ClC6H4, 2; Ar = 4-MeOC6H4, 3), efficiently catalyzed the cross-coupling of various aryl, heteroaryl, and vinyl chlorides with aryl Grignard reagents. Key chemicals used include 4-MeOC6H4Cl, 4-MeC6H4MgBr, 2-chloropyridine and vinyl chlorides like 1-chloro-2-methylprop-1-ene. The study concluded that these complexes are effective catalysts for a wide range of substrates, including activated, unactivated, and deactivated aryl chlorides, heteroaryl chlorides, vinyl chlorides, and 1,4-dichlorobenzene. In contrast, pincer nickel complexes with [5,5]- and [5,6]-fused nickel rings exhibited much lower catalytic activity.