Synthesis, characterization, and applications of novel di-2-pyridyl imine ligands
摘要:
Two novel di-2-pyridyl imines, 2,4,6-trimethyl-(di-2-pyridyl methylene)aniline (1) and 2,6-di-isopropyl-(di-2-pyridyl methylene)aniline (2), were prepared through condensation reactions between 2,2'-dipyridyl ketone and 2,4,6-trimethylaniline and 2,6-di-isopropylaniline. They reacted readily with bis(benzonitrile)dichloropalladium(II) to afford palladium imine complexes. The crystal structure of the palladium complex (3) bearing the 2,4,6-trimethyl-(di-2-pyridylmethylene)aniline ligand revealed coordination of a pyridyl group and an imine group to the metal center. The novel ligands were successfully employed in the Suzuki coupling reaction of p-bromoanisole and phenylboronic acid. (C) 2009 Elsevier B.V. All rights reserved.
Synthesis, characterization, and applications of novel di-2-pyridyl imine ligands
摘要:
Two novel di-2-pyridyl imines, 2,4,6-trimethyl-(di-2-pyridyl methylene)aniline (1) and 2,6-di-isopropyl-(di-2-pyridyl methylene)aniline (2), were prepared through condensation reactions between 2,2'-dipyridyl ketone and 2,4,6-trimethylaniline and 2,6-di-isopropylaniline. They reacted readily with bis(benzonitrile)dichloropalladium(II) to afford palladium imine complexes. The crystal structure of the palladium complex (3) bearing the 2,4,6-trimethyl-(di-2-pyridylmethylene)aniline ligand revealed coordination of a pyridyl group and an imine group to the metal center. The novel ligands were successfully employed in the Suzuki coupling reaction of p-bromoanisole and phenylboronic acid. (C) 2009 Elsevier B.V. All rights reserved.
2,2'-Dipyridyl-N-arylimines L (L-1 = 2,4,6-trimethyl(di-2-pyridylmethylene)aniline, L-2 = 2,6-diisopropyl(di-2-pyridylmethylene)aniline) react with arene ruthenium dichloride dimer in methanol to give cationic arene ruthenium complexes of the general type [(arene)Ru(eta(2)-N,N-L)Cl](+) (arene = C6H6, p-MeC6H4Pri). Two coordination modes of the chelating ligands N,N-L are observed. In the major isomer, the ketimine nitrogen atom and one of the two pyridine nitrogen atoms are coordinated to ruthenium, while in the minor isomer the two pyridine nitrogen atoms coordinate to the metal center. In the case of L-1, the minor isomer of the p-cymene ruthenium chloro complex could be isolated as the tetrafluoroborate salt and characterized by single crystal X-ray analysis. The molecular structure of the major isomer was determined by X-ray crystallography in the case of the tetraphenylborate salt of the benzene ruthenium chloro derivative. In both structures, the ruthenium atom shows the expected pseudo-tetrahedral coordination geometry. (c) 2012 Elsevier B.V. All rights reserved.