Mono- and Dinuclear Pincer Nickel Catalyzed Activation and Transformation of C–Cl, C–N, and C–O Bonds

Abstract

Condensation of 2-NH 2 C 6 H 4 P(Et)Ph (2) with pyrrole-2-carboxaldehyde generated 2-(C 4 H 4 N-2′-CHN)-C 6 H 4 P(Et)Ph (3). Treatment of 3 with NaH and followed by (DME)NiX 2 (X = Cl, Br) afforded mononuclear pincer nickel complexes [Ni{2-(C 4 H 3). Catalysis of the complexes for the activation and transformation of C−Cl, C−N, and C−O bonds was evaluated. Complex 7c exhibited excellent catalytic activity in the cross-coupling of aryl chlorides or aryltrimethylammonium iodides with arylzinc reagents as well as of aryl sulfamates with aryl Grignard reagents. The dinuclear nickel complexes 7b−d showed higher catalytic activity than the mononuclear complexes in each type of reaction.

Transition‐Metal‐Free Reaction of Aryltrimethylammonium Iodides with Arylzinc Reagents

“…In previous studies of transition‐metal‐catalyzed cross‐coupling reactions we noticed that the existence of Mg 2+ and Li + ions greatly affected reactivity of the arylzinc reagents ,. In this study we also examined Mg 2+ and Li + ion effect.…”

Pincer‐Nickel‐Catalyzed Cross‐Coupling of Aryl Sulfamates with Arylzinc Chlorides

“…4′‐Methoxy‐2‐methylbiphenyl: 10c 1 H NMR (400 MHz, CDCl 3 ): δ = 2.27 (s, 3 H), 3.84 (s, 3 H), 6.95 (d, J = 8.8 Hz, 2 H), 7.19–7.28 (m, 6 H) ppm. 13 C NMR (101 MHz, CDCl 3 ): δ = 20.68, 55.41, 113.63, 125.89, 127.11, 130.04, 130.38, 130.43, 134.52, 135.62, 141.69, 158.65 ppm.…”

“…4′‐Methoxy‐ N , N ‐dimethylbiphenyl‐4‐amine: 10c 1 H NMR (400 MHz, CDCl 3 ): δ = 2.95 (s, 6 H), 3.81 (s, 3 H), 6.78 (d, J = 8.8 Hz, 2 H), 6.93 (d, J = 8.8 Hz, 2 H), 7.44 (d, J = 8.8 Hz, 2 H), 7.47 (d, J = 8.8 Hz, 2 H) ppm. 13 C NMR (101 MHz, CDCl 3 ): δ = 39.77, 54.43, 112.04, 113.23, 126.40, 126.42, 128.26, 133.07, 148.72, 157.37 ppm.…”

“…N , N ‐Dimethyl‐4′‐(trifluoromethyl)biphenyl‐4‐amine: 10c 1 H NMR (400 MHz, CDCl 3 ): δ = 3.01 (s, 6 H), 6.80 (d, J = 8.8 Hz, 2 H), 7.52 (d, J = 8.8 Hz, 2 H), 7.61–7.66 (m, 4 H) ppm. 13 C NMR (101 MHz, CDCl 3 ): δ = 40.56, 112.77, 124.67 ( J = 272.7 Hz), 125.73 ( J = 4.0 Hz), 126.34, 127.42, 127.97 ( J = 32.3 Hz), 128.01, 144.80, 150.64 ppm.…”

“…(4′‐Methylbiphenyl‐4‐yl)(phenyl)methanone: 10c 1 H NMR (400 MHz, CDCl 3 ): δ = 2.41 (s, 3 H), 7.28 (d, J = 7.9 Hz, 2 H), 7.49 (t, J = 7.4 Hz, 2 H), 7.55 (d, J = 8.4 Hz, 2 H), 7.57–7.61 (m, 1 H), 7.68 (d, J = 8.4 Hz, 2 H), 7.81–7.85 (m, 2 H), 7.88 (d, J = 8.4 Hz, 2 H) ppm. 13 C NMR (101 MHz, CDCl 3 ): δ = 21.30, 126.83, 127.26, 128.42, 129.83, 130.11, 130.87, 132.45, 136.07, 137.19, 137.97, 138.31, 145.32, 196.49 ppm.…”