Synthesis, structural characterisation and bonding in an anionic hexavanadate bearing redox-active ferrocenyl groups at the periphery

0437165 - ÚFCH JH 2015 RIV GB eng J - Journal Article
Schulz, J. - Gyepes, Robert - Císařová, I. - Štěpnička, P.
Synthesis, structural characterisation and bonding in an anionic hexavanadate bearing redox-active ferrocenyl groups at the periphery.
New Journal of Chemistry. Roč. 34, č. 12 (2010), s. 2749-2756. ISSN 1144-0546. E-ISSN 1369-9261
R&D Projects: GA MŠMT(CZ) LC06070
Institutional research plan: CEZ:AV0Z40400503
Keywords : synthesis * redox-active ferrocenyl groups * ferrocene
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.631, year: 2010

Amide FcCONHC(CH2OH)(3) (1; Fc = ferrocenyl), prepared from fluorocarbonylferrocene and tris(hydroxymethyl)methylamine, reacts with (Bu4N)(3)[H3V10O28] in N, N-dimethylacetamide to afford a salt containing a bis(triolato) capped hexavanadate anion bearing two ferrocenyl groups at its periphery, (Bu4N)(2)[{FcC(O)NHC(CH2O)(3)}(2)V6O13] (2). Compounds 1 and 2 were characterised by elemental analysis, spectroscopic methods (IR, NMR, and MS) and by cyclic voltammetry; the crystal structures of 1.1/2CH(3)CO(2)Et and (Bu4N)(2)[{FcC(O)NHC(CH2O)(3)}(2)V6O13]center dot 2Me(2)NCHO were determined by X-ray diffraction analysis. Single-point DFT calculations performed for the isolated hexavanadate anion revealed the presence of 3-centre 4-electron (3c4e) O-V-O bonds on the hexavanadate cage, which are responsible for the high energy of the occupied frontier orbitals. The upper eleven occupied molecular orbitals including the HOMO are all delocalized over the hexavanadate cage and, therefore, any electrochemical oxidation can be expected to occur preferentially at the hexavanadate anion without affecting the pendant ferrocene moieties.
Permanent Link: http://hdl.handle.net/11104/0240729