Synthese und Struktur von [Re(NH)Cl2(PMe2Ph)3][TaCl6] und [(Me2PhP)3Cl2Re≡N]2VOCl2

Synthesis and Structure of Re(NH)Cl₂(PMe₂Ph)₃]TaCl₆] and (Me₂PhP)₃Cl₂Re≡N]₂VOCl₂ The products of the reaction of ReNCl₂(PMe₂Ph)₃ with TaCl₅ are dependent on the solvent. In CH₂Cl₂ the solvent protonates the nitrido ligand to yield Re(NH)Cl₂(PMe₂Ph)₃]TaCl₆] as air-stable, reddish brown needles with the space group P2₁/n and a = 1213.8(3), b = 1358.0(2), c = 2165.9(4) pm, β = 92.88(1)°, Z = 4. The Re atom of the cation exhibits an octahedral coordination with the phosphine ligands in meridional arrangement. The imido ligand is in trans-position to a Cl atom with a distance Re–N = 170.4(4) pm. When the reaction is carried out in toluene the dinuclear nitrido complex Re(NTaCl₅)Cl₂(PMe₂Ph)₃] is obtained instead. The reaction of ReNCl₂(PMe₂Ph)₃ with VCl₃(THF)₃ in toluene affords the threenuclear complex Re₂N₂Cl₄(PMe₂Ph)₅]VCl₃, which upon crystallization at air gives air-stable, reddish-brown crystals of (Me₂PhP)₃Cl₂ReN]₂VOCl₂. They crystallize in the monoclinic space group P2₁ with a = 1519.2(5), b = 1257.1(1), c = 1564.3(6) pm, β = 102.86(2)°, and Z = 2. The threenuclear complex shows an almost linear arrangement Re≡N–V–N≡Re with distances Re–N 171(2) pm and V–N of 209(2) pm.