Structures of substituted pyridine N-oxide with manganese(II) acetate

Acta Crystallogr E Crystallogr Commun. 2018 Sep 11;74(Pt 10):1405-1410. doi: 10.1107/S205698901801232X. eCollection 2018 Oct 1.

Abstract

Manganese(II) acetate coordination polymers have been prepared with three derivatives of pyridine N-oxide. The compounds are catena-poly[manganese(II)-μ3-acetato-di-μ2-acetato-[aqua-manganese(II)]-μ2-acetato-μ-(pyridine N-oxide)-manganese(II)-μ3-acetato-μ2-acetato-μ-(pyridine N-oxide)-[aqua-manganese(II)]-di-μ2-acetato], [Mn4(CH3COO)8(C5H5NO)2(H2O)2] n , (I), catena-poly[[manganese(II)]-μ3-acetato-μ2-acetato-μ-(2-methyl-pyridine N-oxide)-[aqua-manganese(II)]-di-μ2-acetato-manganese(II)-di-μ2-acetato-μ3-acetato-[aqua-manganese(II)]-μ2-acetato-μ-(2-methyl-pyridine N-oxide)], [Mn4(CH3COO)8(C6H7NO)2(H2O)2] n , (II), and catena-poly[[manganese(II)-di-μ2-acetato-μ-(4-methyl-pyridine N-oxide)] monohydrate], {[Mn(CH3COO)2(C6H7NO)]·H2O} n , (III). Compounds (I) and (II) both have three unique Mn atoms; in both compounds two of them sit on a crystallographic inversion center while the third is on a general position. In compound (III), the single unique Mn atom sits on a general position. Pseudo-octa-hedral six-coordinate mangan-ese(II) centers are found in all compounds. All of the compounds form chains of Mn atoms bridged by acetate ions and the oxygen atom of the N-oxide in pyridine N-oxide (PNO), 2-methyl-pyridine N-oxide (2MePNO), or 4-methyl-pyridine N-oxide (4MePNO). Compound (I) and (II) both exhibit a bound water of solvation. In (I), the water hydrogen bonds to a nearby acetate whereas in (II) the water mol-ecule forms bridging hydrogen bonds between two neighboring acetates. In compound (III) a water mol-ecule of solvation is found in the lattice, not bound to the metal ion but hydrogen bonding to a bridging acetate.

Keywords: coordination polymer; crystal structure; manganese(II) acetate; pyridine N-oxide ligand.

Grants and funding

This work was funded by Armstrong State University grant .