title: A new bis(1-naphthylimino)acenaphthene compound and its Pd(II) and Zn(II) complexes: synthesis, characterization, solid-state structures and density functional theory studies on the syn and anti isomers.
abstract: A new rigid bidentate ligand, bis(1-naphthylimino)acenaphthene, L1, and its Zn(II) and Pd(II) complexes [ZnCl 2( L1)], 1, and [PdCl 2( L1)], 2, were synthesized. L1 was prepared by the "template method", reacting 1-naphthyl amine and acenaphthenequinone in the presence of ZnCl 2, giving 1, which was further demetallated. Reaction of 1-naphthyl amine with acenaphthenequinone and PdCl 2 afforded dichloride bis(1-naphthyl)acenaphthenequinonediimine palladium, 2. L1, 1, and 2 were obtained as a mixture of syn and anti isomers. Compound 2 was also obtained by the reaction of PdCl 2 activated by refluxing it in acetonitrile followed by the addition of L1; by this route also a mixture of syn and anti isomers was obtained, but at a different rate. The solid-state structures of L1 and the anti isomer of compound 2 have been determined by single-crystal X-ray diffraction. All compounds have been characterized by elemental analyses; matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry; IR; UV-vis; (1)H, (13)C, and (1)H- (1)H correlation spectroscopy; (1)H- (13)C heteronuclear single quantum coherence; (1)H- (13)C heteronuclear single quantum coherence-total correlation spectroscopy; and (1)H- (1)H nuclear Overhauser effect spectrometry NMR spectroscopies when applied. Density functional theory studies showed that both conformers for [PdCl 2(BIAN)] are isoenergetic, and they can both be obtained experimentally. However, we can predict that the isomerization process is not available in a square-planar complex, but it is possible for the free ligand. The molecular geometry is very similar in both isomers, and only different orientations for naphthyl groups can be expected.
authors.affiliation: REQUIMTE, Departamento de Quimica, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, 2829-516, Portugal.
authors.forename: Vitor
authors.initials: V
authors.lastname: Rosa
authors.forename: Teresa
authors.initials: T
authors.lastname: Avilés
authors.forename: Gabriel
authors.initials: G
authors.lastname: Aullon
authors.forename: Berta
authors.initials: B
authors.lastname: Covelo
authors.forename: Carlos
authors.initials: C
authors.lastname: Lodeiro
mesh_terms: D000073:Acenaphthenes / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D011789:Quantum Theory; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D015032:Zinc / Q000737:chemistry*
chemical_list: D000073:Acenaphthenes; D009942:Organometallic Compounds; C533504:bis(1-naphthylimino)acenaphthene; D010165:Palladium; D015032:Zinc