title: Mono- and Dinuclear Heteroleptic Cobalt Complexes with α-Diimine and Polyarene Ligands.
abstract: Reactions of the dimeric cobalt complex [(L(-) Co)2 ] (1, L=[(2,6-iPr2 C6 H3 )NC(Me)]2 ) with polyarenes afforded a series of mononuclear and dinuclear complexes: [LCo(η(4) -anthracene)] (2), [LCo(μ-η(4) :η(4) -naphthalene)CoL] (3), and [LCo(μ-η(4) :η(4) -phenanthrene)CoL] (4). The pyrene complexes [{Na2 (Et2 O)2 }{LCo(μ-η(3) :η(3) -pyrene)CoL}] (5) and [{Na2 (Et2 O)3 }{LCo(η(3) -pyrene)}] (6) were obtained by treating precursor 1 with pyrene followed by reduction with Na metal. These complexes contain three potential redox active centers: the cobalt metal and both α-diimine and polyarene ligands. Through a combination of X-ray crystallography, EPR spectroscopy, magnetic susceptibility measurement, and DFT computations, the electronic configurations of these complexes were studied. It was determined that complexes 2-4 have a high-spin Co(I) center coupled with a radical α-diimine ligand and a neutral polyarene ligand. Whereas, the ligand L in complexes 5 and 6 has been further reduced to the dianion, the cobalt remains in a formal (I) oxidation state, and the pyrene molecule is either neutral or monoanionic.
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular, Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (P.R. China).
authors.forename: Xuting
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular, Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (P.R. China).
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Center for Computational Quantum Chemistry, South China Normal University, Guangzhou 510631 (P.R. China).
authors.forename: Shida
authors.initials: S
authors.lastname: Gong
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular, Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (P.R. China).
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.affiliation: Center for Computational Quantum Chemistry, South China Normal University, Guangzhou 510631 (P.R. China).
authors.forename: Qian-Shu
authors.initials: QS
authors.lastname: Li
authors.affiliation: Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (P.R. China).
authors.forename: Ji-Hu
authors.initials: JH
authors.lastname: Su
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular, Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (P.R. China).
authors.forename: Biao
authors.initials: B
authors.lastname: Wu
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular, Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069 (P.R. China). yangxiaojuan@nwu.edu.cn.
authors.forename: Xiao-Juan
authors.initials: XJ
authors.lastname: Yang
keywords: alpha-diimine; cobalt; electronic structure; non-innocent ligands; polyarene