Formation of Bridging Nitride Versus Terminal Oxovanadium Promoted by a Vanadium(II) Macrocyclic Complex

The reaction of [VCl 2 (tmeda) 2 ] with the tetralithium salt of octaethylporphyrinogen (oepg)[Li(thf)] 4 initially yielded a monomeric V II complex [(oepg)‐VLi 4 Cl 2 (thf) 4 ] ( 1 ). Treatment of this species with tetramethylethylenediamine afforded a mixture from which [(oepg)‐V(thf) 2 ][Li(tmeda) 2 ].0.5 toluene ( 2 a ) (or 2 b when ethyl is replaced by n Pr) and the unprecedented nitrido‐bridged dimeric species [{oepg)V} 2 (μ‐N)(μ‐Li) 4 ]‐[Li(tmeda) 2 ] ( 3 ) were isolated and characterized. The bridging nitrogen atom probably originated from the cleavage of dinitrogen, since the same reaction carried out under exclusion of N 2 gave [(oepg)VO]‐[Li(tmeda)] 2 ( 4 ), where the oxo atom probably originated from deoxygenation of THF. The connectivity of 1, 2 b, 3 , and 4 was demonstrated by X‐ray analysis.