Geometrical variations of two manganese(II) complexes with closely related quinoline-based tripodal ligands

Structural analyses of the compounds di-μ-acetato-κ(4) O:O′-bis­{[2-meth­oxy-N,N-bis­(quinolin-2-ylmeth­yl)ethanamine-κ(4) N,N′,N′′,O]manganese(II)} bis­(tetra­phen­yl­borate) di­chloro­methane 1.45-solvate, [Mn(2)(C(23)O(2))(2)(C(23)H(23)N(3)O)(2)](C(24)H(20)B)·1.45CH(2)Cl(2) or [Mn(DQMEA)(μ-OAc)(2)Mn(DQMEA)](BPh(4))(2)·1.45CH(2)Cl(2) or [1](BPh(4))(2)·1.45CH(2)Cl(2), and (acetato-κO)[2-hy­droxy-N,N-bis(quinolin-2-ylmeth­yl)ethanamine-κ(4) N,N′,N′′,O](methanol-κO)manganese(II) tetra­phenyl­borate methanol monosolvate, [Mn(CH(3)COO)(C(22)H(21)N(3)O)(CH(3)OH)](C(24)H(20)B)·CH(3)OH or [Mn(DQEA)(OAc)(CH(3)OH)]BPh(4)·CH(3)OH or [2]BPh(4)·CH(3)OH, by single-crystal X-ray diffraction reveal distinct differences in the geometry of coordination of the tripodal DQEA and DQMEA ligands to Mn(II) ions. In the asymmetric unit, compound [1](BPh(4))(2)·(CH(2)Cl(2))(1.45) crystallizes as a dimer in which each manganese(II) center is coordinated by the central amine nitro­gen, the nitro­gen atom of each quinoline group, and the meth­oxy-oxygen of the tetra­dentate DQMEA ligand, and two bridging-acetate oxygen atoms. The symmetric Mn(II) centers have a distorted, octa­hedral geometry in which the quinoline nitro­gen atoms are trans to each other resulting in co-planarity of the quinoline rings. For each Mn(II) center, a coordinated acetate oxygen participates in C—H⋯O hydrogen-bonding inter­actions with the two quinolyl moieties, further stabilizing the trans structure. Within the crystal, weak π–π stacking inter­actions and inter­molecular cation–anion inter­actions stabilize the crystal packing. In the asymmetric unit, compound [2]BPh(4)·CH(3)OH crystallizes as a monomer in which the manganese(II) ion is coordinated to the central nitro­gen, the nitro­gen atom of each quinoline group, and the alcohol oxygen of the tetra­dentate DQEA ligand, an oxygen atom of OAc, and the oxygen atom of a methanol ligand. The geometry of the Mn(II) center in [2]BPh(4)·CH(3)OH is also a distorted octa­hedron, but the quinoline nitro­gen atoms are cis to each other in this structure. Hydrogen bonding between the acetate oxygen atoms and hydroxyl (O—H⋯O) and quinolyl (C—H⋯O and N—H⋯O) moieties of the DQEA ligand stabilize the complex in this cis configuration. Within the crystal, dimerization of complexes occurs by the formation of a pair of inter­molecular O3—H3⋯O2 hydrogen bonds between the coordinated hydroxyl oxygen of the DQEA ligand of one complex and an acetate oxygen of another. Additional hydrogen-bonding and inter­molecular cation–anion inter­actions contribute to the crystal packing.