Room‐temperature Suzuki–Miyauracross‐coupling reaction with α‐diimine Pd(II) catalysts

Abstract

An α‐diimine Pd(II) complex containing chiral sec‐phenethyl groups, {bis[N,N′‐(4‐methyl‐2‐sec‐phenethylphenyl)imino]‐2,3‐butadiene}dichloropalladium (rac‐C1), was synthesized and characterized. rac‐C1 was applied as an efficient catalyst for the Suzuki–Miyaura cross‐coupling reaction between various aniline halides and arylboronic acid in PEG‐400–H2O at room temperature. Among a series of aniline halides, rac‐C1 did not catalyze the cross‐coupling of aniline chlorides and fluorides but efficiently catalyzed the cross‐coupling of aniline bromides and iodides with phenylboronic acid. The catalytic activity reduced slightly with increasing steric hindrance of the aniline bromides. The complexes {bis[N,N′‐(4‐fluoro‐2,6‐diphenylphenyl)imino]‐2,3‐butadiene}dichloropalladium and {bis[N,N′‐(4‐fluoro‐2,6‐diphenylphenyl)imino]acenaphthene}dichloropalladium were also found to be efficient catalysts for the reaction. Copyright © 2015 John Wiley & Sons, Ltd.

Synthesis of highly branched polyethylene using para‐phenyl‐substituted α‐diimine nickel catalysts

“…Formic acid (0.2 ml) was added to a stirred solution of 2,3‐butanedione (0.17 g, 2.00 mmol) and 2,6‐diisopropyl‐4‐phenylaniline (1.01 g, 4.00 mmol) in MeOH (35 ml). The mixture was refluxed for 12 h, and then cooled, and the precipitate was separated by filtration.…”

“…Dichloromethane, toluene, tetrahydrofuran and hexanes were purified by solvent purification systems. All para ‐phenylaniline derivatives and complexes 5 were prepared according to reported procedures. All other reagents were purchased from commercial sources and used without purification.…”

Precision Chain‐Walking Polymerization of trans‐4‐Octene Catalyzed by α‐Diimine Nickel(II) Catalysts Bearing ortho‐sec‐Phenethyl Groups

“…We have previously reported that bulky ortho‐sec‐ phenethyl ‐ substituted and ortho‐ phenyl substituted α‐ diimine nickel and palladium complexes exhibited high activities toward ethylene polymerization and produced highly branched polyethylene upon activation with Et 2 AlCl or MMAO, and also produced branched poly(1‐alkene)s with high molecular weight. We anticipated that bulky α‐ diimine ligands might control chain walking and produce regioregular polymers.…”

Cationic para‐phenyl‐substituted α‐diimine nickel catalyzed ethylene and 4‐methyl‐1‐pentene (co)polymerizations via living/controlled chain‐walking

“…A solution of 2,3‐butanedione (0.17 g, 2.00 mmol), 2‐ethyl‐6‐methy ‐ 4 ‐ phenylaniline (0.84 g, 4.00 mmol), and formic acid (0.2 ml) in MeOH (35 mL) was heated to reflux for 12 h. The mixture was cooled, and the precipitate was separated by filtration. The yellow solid was washed with cold ethanol and dried under vacuum (0.71 g, 75% yield).…”