P,N,N-Pincer nickel-catalyzed cross-coupling of aryl fluorides and chlorides

P,N,N-Pincer nickel complexes [Ni(Cl){N(2-R2PC6H4)(2'-Me2NC6H4)}] (R = Ph, 3a; R = Pr-i, 3b; R = Cy, 3c) were synthesized and their catalysis toward the Kumada or Negishi cross-coupling reaction of aryl fluorides and chlorides was evaluated. Complex 3a effectively catalyzes the cross-coupling of (hetero)aryl fluorides with aryl Grignard reagents at room temperature. Complex 3a also catalyzes the cross-coupling of (hetero) aryl chlorides and arylzinc reagents at 80 degrees C with low catalyst loadings and good functional group compatibility.