A manganese(II) dichloro-bridged one-dimensional polymer: Structural, fluorescence and low-temperature magnetic study

Effective catalytic disproportionation of aqueous H2O2 with di- and mono-nuclear manganese(II) complexes containing pyridine alcohol ligands

The two novel manganese(II) complexes with 2-hydroxymethylpyridine (2-CH2OHpy) {[Mn2(μ-Cl)2(2-CH2OHpy)4]Cl2·2H2O (1)} and 2-hydroxyethylpyridine (2-(CH2)2OHpy) {[Mn(2-(CH2)2OHpy)2(NCS)2] (2)} were synthesized and characterized by means of X-ray diffraction, IR, EPR, HF EPR spectroscopy, magnetic and TG/DTG data. The complexes show catalase-like activity in neutral aqueous solution since they were able to disproportionate H2O2 to harmless H2O and O2. Both complexes act as true catalysts since they reverted to their original form after depleting all the H2O2, as suggested by the operando resonant inelastic X-ray spectroscopy (RIXS) measurements.

Dichlorido(2,9-dimeth-oxy-1,10-phenanthroline-κN,N')zinc(II)

In the crystal structure of the title compound, [ZnCl₂(C₁₄H₁₂N₂O₂)], the Zn^II center is four-coordinated by two N atoms from one 2,9-dimeth­oxy-1,10-phenanthroline ligand and two Cl atoms. The coordination geometry is distorted tetra­hedral, as the Zn—N bond distances are shorter than the Zn—Cl distances, and the Cl—Zn—N and Cl—Zn—Cl bond angles are much larger than the N—Zn—N angle. For the ligand, the O and C atoms of the meth­oxy groups are almost in the plane defined by the phenanthroline ring. The two O atoms deviate from the phenanthroline mean plane by 0.076 (2) and 0.084 (2) Å, and the two methyl C atoms deviate from the phenanthroline mean plane by 0.035 (3) and 0.361 (3) Å. There are medium π–π stacking interactions between two parallel phenanthroline rings with a centroid–centroid distance of 3.7860 (2) Å and a dihedral angle between the plane defined by the two parallel phenanthroline rings of 1.13 (5)°.

Dichlorido(2,9-dieth-oxy-1,10-phenanthroline-κN,N')zinc(II)

All non-H atoms except for the Cl atoms lie on a mirror plane in the title complex, [ZnCl(2)(C(16)H(16)N(2)O(2))]. The Zn(II) ion is coordinated by two N atoms from a bis-chelating 2,9-dieth-oxy-1,10-phenanthroline ligand and two symmetry-related Cl atoms in a distorted tetra-hedral environment. The two Zn-N bond lengths are significantly different from each other and the N-Zn-N angle is acute. In the crystal structure, there are weak but significant π-π stacking inter-actions between phenanthroline rings, with a centroid-centroid distance of 3.764 (1) Å.

(2,9-Dieth-oxy-1,10-phenanthroline-κN,N')bis-(thio-cyanato-κN)cobalt(II)

In the title complex, [Co(NCS)₂(C₁₆H₁₆N₂O₂)], the Co^II ion is coordinated by two N atoms from one 2,9-dieth­oxy-1,10-phenanthroline ligand and two N atoms from two different thio­cyanate ligands in a distorted tetra­hedral environment. The Co—N bonds involving the thio­cyanate ligands are significantly shorter than the other two Co—N bonds. The atoms of one of the eth­oxy groups are essentially coplanar with the phenanthroline ring [N=C—O—C = 178.8 (4)°], while the other eth­oxy group is slightly twisted from the phenanthroline ring plane [N=C—O—C = 167.2 (4)°]. In the crystal structure, there is a weak π–π stacking inter­action between two symmetry-related phenanthroline rings with a centroid–centroid distance of 3.706 (4) Å.