title: Bioinspired hydrogen bond motifs in ligand design: the role of noncovalent interactions in metal ion mediated activation of dioxygen.
abstract: Hydrogen bonds influence secondary coordination spheres around metal ions in many proteins. To duplicate these features of molecular architecture in synthetic systems, urea-based ligands have have been developed that create rigid organic frameworks when bonded to metal ions. These frameworks position hydro-gen bond donors proximal to metal ion(s) to form specific chem-ical microenvironments. Iron(II) and manganese(II) complexes with constrained cavities activate O(2), yielding M(III) (M(III) = Fe and Mn) complexes with terminal oxo ligands. Installation of anionic sites within the cavity assists the formation of complexes with M(II/III)-OH and M(III)-O units derived directly from water. Opening the cavity promotes M(mu-O)(2)M rhombs, as illustrated by isolation of a cobalt(III) analogue, the stability of which is promoted by the hydrogen bonds surrounding the bridging oxo ligands.
authors.affiliation: Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA.
authors.forename: A S
authors.initials: AS
authors.lastname: Borovik
mesh_terms: D003035:Cobalt / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry; D006860:Hydrogen Bonding; D007477:Ions; D008024:Ligands; D017895:Manganese Compounds / Q000737:chemistry; D008667:Metalloproteins / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D005296:Ferrous Compounds; D007477:Ions; D008024:Ligands; D017895:Manganese Compounds; D008667:Metalloproteins; D008670:Metals; D009942:Organometallic Compounds; D010087:Oxides; D003035:Cobalt; C027424:manganese oxide; D010100:Oxygen