title: Self-ordering of metallogrid complexes via directed hydrogen-bonding.
abstract: Reaction of imidazole aldehydes with dihydrazino derivatives of 2-phenylpyrimidine provides a family of bis(acylhydrazone) ligands which form [2 × 2] metallogrid complexes with transition metal ions including Fe(II), Co(II), Cu(II) and Zn(II). The free ligands show H-bonding interactions, both donor and acceptor, largely involving the imidazole units, while binding of the metal ions occupies all the acceptor sites and leaves only the pyrrolic-NH site as an H-bond donor, although its deprotonation by a strong base can regenerate an acceptor. These H-bonding interactions have been studied by (1)H NMR spectroscopy in solution and in the solid state by means of several crystal structure determinations. The Fe(II) grids appear to be exclusively high-spin species over a wide temperature range in solution. In the solid state various forms of spin-crossover behaviour can be observed between 1.8 and 300 K, which has been rationalised in terms of the varied forms of hydrogen-bonding possible in the crystalline state.
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaires, Université de Strasbourg, France.
authors.forename: Artur R
authors.initials: AR
authors.lastname: Stefankiewicz
authors.forename: Guillaume
authors.initials: G
authors.lastname: Rogez
authors.forename: Jack
authors.initials: J
authors.lastname: Harrowfield
authors.forename: Alexandre N
authors.initials: AN
authors.lastname: Sobolev
authors.forename: Augustin
authors.initials: A
authors.lastname: Madalan
authors.forename: Juhani
authors.initials: J
authors.lastname: Huuskonen
authors.forename: Kari
authors.initials: K
authors.lastname: Rissanen
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Lehn
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D006835:Hydrazones / Q000138:chemical synthesis / Q000737:chemistry*; D006860:Hydrogen Bonding; D007093:Imidazoles / Q000737:chemistry; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D028561:Transition Elements / Q000737:chemistry
chemical_list: D000447:Aldehydes; D006835:Hydrazones; D007093:Imidazoles; D008024:Ligands; D009942:Organometallic Compounds; D028561:Transition Elements