Synthesis, characterization and magnetic properties of head-to-head stacked vanadocenes. Issue 44 (1st November 2017)

• Record Type: Journal Article
• Authors: Puhl, Sarah; Steenbock, Torben; Harms, Reentje; Herrmann, Carmen; Heck, Jürgen
• Is Part Of: Dalton transactions. Volume 46:Issue 44(2017)
• Page Start: 15494
• Page End: 15502
• Publication Date: 2017-11-01
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c7dt03101g
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Despite six unpaired electrons, this bisvanadocenyl complex shows poor antiferromagnetic exchange coupling due to both weak through-space and through-bond interactions. Abstract : In order to design magnetically active molecular materials, it is desirable to arrange paramagnetic molecules in one dimension, which may lead to a molecular bar magnet. For this purpose, vanadocenyl units with three unpaired electrons each can be stacked in a head-to-head fashion. The target compound in this work is 1, 8-bisvanadocenyl naphthalene, where the naphthalene backbone serves as a clamp keeping two vanadocene units together. The target compound in this work is obtained through the reaction of the disodium salt of 1, 8-biscyclopentadiendiylnaphthalene with the cyclopentadienyl vanadium (CpV) transfer reagent [V(μ2 -Cl)(η 5 -Cp)(thf)]2 . The 1, 8-bisvanadocenyl naphthalene is fully characterized. In addition, variable temperature 1 H NMR spectroscopy, X-ray structure analysis, magnetic measurements and DFT calculations have been performed. In both experiment and theory, a weak antiferromagnetic coupling between the spin centers is found, with the spin highly localized on the V(ii ) ions.