Anion-Assisted Crystallization of a Novel Type of Rhenium(IV)-Based Salt

A novel rhenium­(IV)–manganese­(II) double salt of formula (NBu₄)₁₀[{ReCl₄(ox)}₃Mn]₂[ReCl₆] (1) (NBu₄⁺ = tetra-n-butylammonium cation and ox^2– = oxalate dianion) has been prepared through the simultaneous use of two different anionic Re^IV complexes, namely, [ReCl₄(ox)]^2– and [ReCl₆]^2–, in the presence of Mn^II ion, the [ReCl₆]^2– anion playing a key role in the crystallization process. 1 has been magnetically characterized and its crystal structure determined by single-crystal X-ray diffraction. The study of the magnetic properties reveals the occurrence of intramolecular antiferromagnetic exchange between Re^IV and Mn^II ions. Remarkably, 1 is the first reported example of Re^IV salt based on two different anionic Re^IV complexes.