title: Meso-helicates with rigid angular tetradentate ligand: design, molecular structures, and progress towards self-assembly of metal-organic nanotubes.
abstract: The self-assembly of two novel metallosupramolecular complexes of the general formulas [L2M2(CH3CN)4][BF4]4 (M = Co, 1a; M = Ni, 1b), where L stands for the tetradentate ligand 3,5-bis[4-(2,2'-dipyridylamino)phenylacetylenyl]toluene, is reported together with their molecular structures ascertained by single-crystal X-ray diffraction studies. Complexes 1a and 1b are isostructural and show the formation of dinuclear meso-helicates with the two octahedral metal centers displaying respectively Δ and Λ configurations. These meso-helicates display large nanocavities with metal---metal separation distance of >2 nm; furthermore, π-π-stacking occurs among individual units to form one-dimensional (1D) polymers which further autoassemble in another direction through π-π contacts among neighboring chains to generate a two-dimensional (2D) network with regular nanocavities. Our approach might be of interest to prepare metal-organic nanotubes via a bottom-up strategy depending on the assembling functional ligand and the geometry of molecular building block.
authors.affiliation: UPMC Université Paris 06 , Institut Parisien de Chimie Moléculaire (UMR CNRS 7201), 4 Place Jussieu, C. 42, 75252 Paris Cedex 05, France.
authors.forename: Rodrigue
authors.initials: R
authors.lastname: Djeda
authors.forename: Christophe
authors.initials: C
authors.lastname: Desmarets
authors.forename: Lise-Marie
authors.initials: LM
authors.lastname: Chamoreau
authors.forename: Yanling
authors.initials: Y
authors.lastname: Li
authors.forename: Yves
authors.initials: Y
authors.lastname: Journaux
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Gontard
authors.forename: Hani
authors.initials: H
authors.lastname: Amouri