Heterocyclic carbene and cyclic (alkyl)(amino)carbene complexes of vanadium() and vanadium()

[VCl 3 (THF) 3 ] offers a convenient entrance point into the chemistry of carbene stabilized V( iii ) complexes. Herein we report the paramagnetic mono- and biscarbene complexes [VCl 3 (cAAC Me )] 1 , [VCl 3 (cAAC Me )(THF)] 1(thf) , [VCl 3 (IMes)] 2 , [{VCl 2 (IiPr Me )(μ-Cl)} 2 ] 3 , [VCl 3 (IDipp)] 4 , [VCl 3 (SIDipp)] 5 , [VCl 3 (SIDipp)(THF)] 5(thf) , [VCl 3 (I t Bu)] 6 , [VCl 3 (cAAC Me ) 2 ] 7 and [VCl 3 (IiPr Me ) 2 ] 8 . Reaction of 1 with MesMgCl, MesLi and LiNPh 2 afforded the complexes [VCl 2 (Mes)(cAAC Me )] 9 , [cAAC Me H] + [VCl 2 Mes 2 ] − 10 and [VCl 2 (NPh 2 )(cAAC Me )] 11 . The V( v ) complexes [V(O)Cl 3 (IDipp)] 12 and [V(O)Cl 3 (SIDipp)] 13 were selectively prepared from oxygen oxidation of 4 and 5 . [V(O)Cl 3 (IDipp)] 12 and [V(O)Cl 3 (IMes)] react with isocyanates to yield the NHC-ligated imido complexes [V(N- p -CH 3 C 6 H 4 )Cl 3 (IDipp)] 14 , [V(N- p -FC 6 H 4 )Cl 3 (IDipp)] 15 , [V(N- p -CH 3 C 6 H 4 )Cl 3 (SIDipp)] 16 , [V(N- p -FC 6 H 4 )Cl 3 (SIDipp)] 17 , [V(N- p -CH 3 C 6 H 4 )Cl 3 (IMes)] 18 and [V(N- p -FC 6 H 4 )Cl 3 (IMes)] 19 . The synthesis, characterization, and molecular structures of NHC and cAAC Me stabilized V( iii ) and V( v ) complexes are presented.