[Cr(N)Cl4]2-: a simple nitrido complex synthesized by nitrogen-atom transfer.

A new general route to nitrido complexes of Cr(V) based on nitrogen-atom transfer from Mn(N)(salen) to labile CrCl3(THF)3 is presented. By this approach, the simplest nitrido complex of a first row transition metal, [Cr(N)Cl4]2-, has been synthesized and isolated. [[N(CH3)4]2[Cr(N)Cl4].H2O crystallizes in the cubic space group Fm-3m with disordered anions. Cr-N is 1.555(19) A, Cr-Cl is 2.2912(16) A, and N-Cr-Cl is 101.24(4) degrees . The orbital splitting scheme of [Cr(N)Cl4]2- is extreme with the dx2-y2 orbital 10 000 cm-1 lower in energy than the degenerate {dzx, dyz} set of orbitals destabilized by pi-bonding with the nitrido ligand. Hydrolysis of [Cr(N)Cl4]2 preserves the {CrN}2+ moiety.