Crystal structure of a seven-coordinate manganese(II) complex with tris­(pyridin-2-ylmeth­yl)amine (TMPA)

Structural analysis of (acetato-κ(2) O,O′)(methanol-κO)[tris­(pyridin-2-ylmeth­yl)amine-κ(4) N,N′,N′′,N′′′]manganese(II) tetraphenyl­borate, [Mn(C(2)H(3)O(2))(C(18)H(18)N(4))(CH(3)OH)](C(24)H(20)B) or [Mn(TMPA)(Ac)(CH(3)OH)]BPh(4) [TMPA = tris­(pyridin-2-ylmeth­yl)amine, Ac = acetate, BPh(4) = tetra­phenyl­borate] by single-crystal X-ray diffraction reveals a complex cation with tetra­dentate coordination of the tripodal TMPA ligand, bidentate coordination of the Ac ligand and monodentate coordination of the methanol ligand to a single Mn(II) center, balanced in charge by the presence of a tetra­phenyl­borate anion. The Mn(II) complex has a distorted penta­gonal–bipyramidal geometry, in which the central amine nitro­gen and two pyridyl N atoms of the TMPA ligand, and two oxygen atoms of the acetate ligand occupy positions in the penta­gonal plane, while the third pyridyl nitro­gen of TMPA and the oxygen from the methanol ligand occupy the axial positions. Within the complex, the acetate O atoms participate in weak C—H⋯O hydrogen-bonding inter­actions with neighboring pyridyl moieties. In the crystal, complexes form dimers by pairs of O—H⋯O hydrogen bonds between the coordinated methanol of one complex and an acetate oxygen of the other, and weak π-stacking inter­actions between pyridine rings. Separate dimers then undergo additional π-stacking inter­actions between the pyridine rings of one moiety and either the pyridine or phenyl rings of another moiety that further stabilize the crystal.