Crystal structure of bis­(5-bromo-1,10-phenanthroline-κ2N,N′)bis­­[di­hydro­bis­­(pyrazol-1-yl)borato-κ2N2,N2′]iron(II) toluene disolvate

The structure determination of the title compound was undertaken as part of a project on the modification and synthesis of new spin-crossover (SCO) compounds based on octa­hedral FeII bis­(pyrazol­yl)borate complexes. In the course of these investigations, the compound [Fe(C6H8BN4)2(C12H7BrN2)] was synthesized, for which magnetic measurements revealed an incomplete spin-crossover behaviour. Crystallization of this compound from toluene led to the formation of crystals of the toluene disolvate, [Fe(C6H8N4B)2(C12H7N2Br)]·2C7H8. Its asymmetric unit comprises two discrete metal complex mol­ecules and two toluene solvent mol­ecules. One of the latter is severely disordered and its contribution to the diffracted intensities was removed using the SQUEEZE routine [Spek (2015[Spek, A. L. (2015). Acta Cryst. C71, 9-18.]). Acta Cryst. C71, 9–18]. In each complex mol­ecule, the FeII cation is coordinated by the two N atoms of a 5-bromo-1,10-phenanthroline ligand and by two pairs of N atoms of chelating di­hydro­bis(pyrazol-1-yl)borate ligands in the form of a slightly distorted octa­hedron. The discrete complexes are arranged in columns along the a-axis direction with the toluene solvate mol­ecules located between the columns. The 5-bromo-1,10-phenanthroline ligands of neighbouring columns are approximately parallel and are slightly shifted relative to each other, indicating π–π inter­actions.