Paramagnetic Chloro‐, Alkoxo‐, or Azidovanadium( IV ) Complexes Supported by an [ONNO]‐Type Amine Bis(phenolate) Ligand

The reactions between V(N 3 ) 2 (NMe 2 ) 2 or V(O i Pr) 4 and the chelating dianionic bis(phenoxy)amine ligand [ONNO]H 2 afford complexes formulated as [V(N 3 ) 2 {ONNO}] ( 1 ) and [V(O i Pr) 2 {ONNO}] ( 2 ). When refluxed in toluene with an excess of Me 3 SiCl, compound 2 leads to mono‐ or dichloro derivatives [V(Cl)(O i Pr){ONNO}] ( 3 ) and [VCl 2 {ONNO}] ( 4 ) depending on the experimental conditions. The crystal structures of complexes 1 − 4 were solved and show in all cases an [ONNO] ligand that has phenolate groups in a trans configuration, with both amino‐nitrogen donor atoms of the ligand coordinated to the octahedral vanadium center. Complexes 1 − 4 were further characterized by EPR spectroscopy and susceptibility measurement studies typical of d 1 ‐paramagnetic V IV species. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)