title: Disubstituted 1,8-diamidonaphthalene ligands as a flexible, responsive, and reactive framework for tantalum complexes.
abstract: Deprotonated N,N'-disubstituted 1,8-diaminonaphthalenes (R(2)DAN(2-); R = (CH(3))(2)CH, C(6)H(5), 3,5-Me(2)C(6)H(3)) were incorporated into Ta(V) complexes employing two methods. The direct proton transfer reaction of the parent amine, 1,8-(RNH)(2)C(10)H(6), with TaMe(3)Cl(2) led to elimination of methane and formation of TaCl(3)[1,8-(RN)(2)C(10)H(6)] (1, 2). Reaction of the dilithiated amido species, Li(2)R(2)DAN, with TaMe(3)Cl(2) or [Ta(NEt(2))(2)Cl(3) ] yielded TaMe(3)[1,8-(RN)(2)C(10)H(6)] (3, 4) and TaCl(NEt(2))(2)[1,8-(RN)(2)C(10)H(6)] (5, 6), respectively. X-ray structural studies of these complexes revealed the flexible coordination behavior of R(2)DAN(2-) by demonstrating that the ligand bonded to Ta with a coordination array dependent on the identity of the other ligands bonded to tantalum. Computational analysis of these complexes confirmed that the energetic components for binding of R(2)DAN(2-) to these TaX(3)(2+) fragments were dominated by the electronic features of the metal fragment. Chemical transformations of the bound ligand were evaluated by reaction of compounds 5 and 6 with LiNMe(2) and MeLi. Simple metathesis products Ta(NEt(2))(2)NMe(2)[1,8-((i)PrN)(2)C(10)H(6)] (R = (i)Pr 7, R = 3,5-Me(2)(C(6)H(3)) 8) were obtained from reactions with LiNMe(2). In contrast, when the R group of the DAN ligand was (i)Pr, reaction with MeLi ultimately led to activation of the isopropyl group and formation of the metallaziridine [kappa(3)-(Me(2)CN)((i)PrN)C(10)H(6)]Ta(NEt(2))(2) (9) species via the elimination of methane.
authors.affiliation: Department of Chemistry and the Center for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Lavoie
authors.forename: Serge I
authors.initials: SI
authors.lastname: Gorelsky
authors.forename: Zhixian
authors.initials: Z
authors.lastname: Liu
authors.forename: Tara J
authors.initials: TJ
authors.lastname: Burchell
authors.forename: Glenn P A
authors.initials: GP
authors.lastname: Yap
authors.forename: Darrin S
authors.initials: DS
authors.lastname: Richeson
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives* / Q000737:chemistry; D018360:Crystallography, X-Ray; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013635:Tantalum / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D013635:Tantalum; D015081:2-Naphthylamine