Oxidative atom-transfer to a trimanganese complex to form Mn6(μ6-E) (E = O, N) clusters featuring interstitial oxide and nitride functionalities

J Am Chem Soc. 2011 Oct 26;133(42):16750-3. doi: 10.1021/ja2066384. Epub 2011 Sep 30.

Abstract

Utilizing a hexadentate ligand platform, a trinuclear manganese complex of the type ((H)L)Mn(3)(thf)(3) was synthesized and characterized ([(H)L](6-) = [MeC(CH(2)N(C(6)H(4)-o-NH))(3)](6-)). The pale-orange, formally divalent trimanganese complex rapidly reacts with O-atom transfer reagents to afford the μ(6)-oxo complex ((H)L)(2)Mn(6)(μ(6)-O)(NCMe)(4), where two trinuclear subunits bind the central O-atom and the ((H)L) ligands cooperatively bind both trinuclear subunits. The trimanganese complex ((H)L)Mn(3)(thf)(3) rapidly consumes inorganic azide ([N(3)]NBu(4)) to afford a dianionic hexanuclear nitride complex [((H)L)(2)Mn(6)(μ(6)-N)](NBu(4))(2), which subsequently can be oxidized with elemental iodine to ((H)L)(2)Mn(6)(μ(6)-N)(NCMe)(4). EPR and alkylation of the interstitial light atom substituent were used to distinguish the nitride from the oxo complex. The oxo and oxidized nitride complexes give rise to well-defined Mn(II) and Mn(III) sites, determined by bond valence summation, while the dianionic nitride shows a more symmetric complex, giving rise to indistinguishable ion oxidation states based on crystal structure bond metrics.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Manganese / chemistry
  • Models, Molecular
  • Molecular Structure
  • Nitrogen / chemistry*
  • Organometallic Compounds / chemistry
  • Oxidation-Reduction
  • Oxides / chemistry
  • Oxygen / chemistry*

Substances

  • Organometallic Compounds
  • Oxides
  • Manganese
  • Nitrogen
  • Oxygen