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

Manganese(II) acetate coordination polymers have been prepared with three derivatives of pyridine N-oxide. The compounds are catena-poly[manganese(II)-μ 3 -acetato-di-μ 2 -acetato-[aquamanganese(II)]-μ 2 -acetato-μ-(pyridine N-oxide)-manganese(II)-μ 3 -acetato-μ 2 -acetato-μ-(pyridine N-oxide)-[aquamanganese(II)]-di-μ 2 -acetato], [Mn 4 (CH 3 COO) 8 (C 5 H 5 NO) 2 (H 2 O) 2 ] n, (I), catena-poly[[manganese(II)]-μ 3 -acetato-μ 2 -acetato-μ-(2-methylpyridine N-oxide)-[aquamanganese(II)]-di-μ 2 -acetato-manganese(II)-di-μ 2 -acetato-μ 3 -acetato-[aquamanganese(II)]-μ 2 -acetato-μ-(2-methylpyridine N-oxide)], [Mn 4 (CH 3 COO) 8 (C 6 H 7 NO) 2 (H 2 O) 2 ] n, (II), and catena-poly[[manganese(II)-di-μ 2 -acetato-μ-(4-methylpyridine N-oxide)] monohydrate], {[Mn(CH 3 COO) 2 (C 6 H 7 NO)]·H 2 O} 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-octahedral six-coordinate manganese(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-methylpyridine N-oxide (2MePNO), or 4-methylpyridine 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 molecule forms bridging hydrogen bonds between two neighboring acetates. In compound (III) a water molecule of solvation is found in the lattice, not bound to the metal ion but hydrogen bonding to a bridging acetate.